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2022 Volume 33 Issue 4
2022, 33(4): 1647-1649
doi: 10.1016/j.cclet.2021.08.065
Abstract:
2022, 33(4): 1650-1658
doi: 10.1016/j.cclet.2021.10.052
Abstract:
In 2020, the MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had made progresses in several aspects. First, a series of metal-free organoboron catalysts had been designed and synthesized facilely, exhibiting outstanding reactivity, thermalstability and productivity in different kinds of polymerization and cycloaddition reactions. Second, a variety of chalcogen (O, S, Se)-rich polymers had been synthesized via organocatalysis and fabricated to be the ionic conductive and photoluminescent materials. Third, diverse microenvironment-sensitive nanoparticles had been designed, and novel strategies had been realized, to enhance the therapeutic efficacy in cancer as well as biofilm-associated infections. Fourth, m6A modification on cellular transcriptome-wide messenger RNA had been successfully mapped at single base resolution using a metabolic labeling method. Fifth, a hydrogel-based robot had been developed, showing swift locomotion as a response to dynamic light stimulations. Sixth, the conformation-size scaling law and the conformation evolution map of 2D macromolecules in solution had been elucidated experimentally, in the single-layer graphene oxide model. Seventh, semitransparent polymer solar cells, promising as building-integrated photovoltaics, have been developed with the fine balance among power conversion efficiency, visible light transparency and infrared photon radiation rejection. Finally, long-range ordered bulk-heterojunctions of organic semiconductors had been achieved, and their superior optoelectronic properties and potential application in photoelectric conversion had been revealed. The related work progresses are reviewed in this paper.
In 2020, the MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had made progresses in several aspects. First, a series of metal-free organoboron catalysts had been designed and synthesized facilely, exhibiting outstanding reactivity, thermalstability and productivity in different kinds of polymerization and cycloaddition reactions. Second, a variety of chalcogen (O, S, Se)-rich polymers had been synthesized via organocatalysis and fabricated to be the ionic conductive and photoluminescent materials. Third, diverse microenvironment-sensitive nanoparticles had been designed, and novel strategies had been realized, to enhance the therapeutic efficacy in cancer as well as biofilm-associated infections. Fourth, m6A modification on cellular transcriptome-wide messenger RNA had been successfully mapped at single base resolution using a metabolic labeling method. Fifth, a hydrogel-based robot had been developed, showing swift locomotion as a response to dynamic light stimulations. Sixth, the conformation-size scaling law and the conformation evolution map of 2D macromolecules in solution had been elucidated experimentally, in the single-layer graphene oxide model. Seventh, semitransparent polymer solar cells, promising as building-integrated photovoltaics, have been developed with the fine balance among power conversion efficiency, visible light transparency and infrared photon radiation rejection. Finally, long-range ordered bulk-heterojunctions of organic semiconductors had been achieved, and their superior optoelectronic properties and potential application in photoelectric conversion had been revealed. The related work progresses are reviewed in this paper.
2022, 33(4): 1659-1672
doi: 10.1016/j.cclet.2021.09.085
Abstract:
As a new type of carbon-based fluorescent nanomaterials, carbon dots (CDs) are provided with the advantages of small size, excellent photoluminescence (PL) property, easy surface modification, robust stability, good water solubility and biocompatibility, which endow them with great potential in sensing. In this review, we first describe the preparation of CDs from different starting materials via various techniques, and pre-/post-modification strategies to modulate their PL properties. Second, we outline the optical properties of CDs, including UV-vis absorption and PL, especially the PL mechanisms of CDs are presented in detail from the size effect, molecular state, surface state and defect state. Third, we summarize the research progress of CDs in sensing environmental pollutants, bioactive substances, biological microenvironments, bacteria and viruses via different mechanisms. In addition, we envision the future development trends and prospects for CDs-based nanosensors. We believe that this type of small nanoparticles will bring about big prospect in the near future.
As a new type of carbon-based fluorescent nanomaterials, carbon dots (CDs) are provided with the advantages of small size, excellent photoluminescence (PL) property, easy surface modification, robust stability, good water solubility and biocompatibility, which endow them with great potential in sensing. In this review, we first describe the preparation of CDs from different starting materials via various techniques, and pre-/post-modification strategies to modulate their PL properties. Second, we outline the optical properties of CDs, including UV-vis absorption and PL, especially the PL mechanisms of CDs are presented in detail from the size effect, molecular state, surface state and defect state. Third, we summarize the research progress of CDs in sensing environmental pollutants, bioactive substances, biological microenvironments, bacteria and viruses via different mechanisms. In addition, we envision the future development trends and prospects for CDs-based nanosensors. We believe that this type of small nanoparticles will bring about big prospect in the near future.
2022, 33(4): 1673-1680
doi: 10.1016/j.cclet.2021.10.057
Abstract:
Nanoparticle-based disease detection, prevention and therapies have gained increased interests in biomedical applications, owing to their significant advantages in therapeutic efficacy and safety. Nonetheless, suffering from the challenges including fast recognition and clearance of foreign nanoparticles by innate immune system before arriving at diseased regions, clinical applications of nanoparticles are usually intercepted. Among various strategies for reducing non-specific phagocytosis and enhancing disease-targeting efficiency of nanoparticles, membrane coating nanotechnology exhibits great potential in the disease diagnosis and therapeutics due to both the structural and functional preservation of membrane proteins from source cells. Benefiting the inherited immune-regulation capacities, this review mainly summarized the latest development of such biomimetic nanoparticles for immunotherapy in treating immune-related diseases including microbial infections, inflammation, tumor and autoimmune diseases.
Nanoparticle-based disease detection, prevention and therapies have gained increased interests in biomedical applications, owing to their significant advantages in therapeutic efficacy and safety. Nonetheless, suffering from the challenges including fast recognition and clearance of foreign nanoparticles by innate immune system before arriving at diseased regions, clinical applications of nanoparticles are usually intercepted. Among various strategies for reducing non-specific phagocytosis and enhancing disease-targeting efficiency of nanoparticles, membrane coating nanotechnology exhibits great potential in the disease diagnosis and therapeutics due to both the structural and functional preservation of membrane proteins from source cells. Benefiting the inherited immune-regulation capacities, this review mainly summarized the latest development of such biomimetic nanoparticles for immunotherapy in treating immune-related diseases including microbial infections, inflammation, tumor and autoimmune diseases.
2022, 33(4): 1681-1692
doi: 10.1016/j.cclet.2021.10.054
Abstract:
Cancer is one of the leading causes of human death around the world. Phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), is an emerging light-triggered cancer treatment and shows the advantages of non-invasiveness and low side effects. The design and preparation of efficient phototherapeutic agents are of great significance for phototherapy. Diketopyrrolopyrrole (DPP) is a small molecular organic dye featuring outstanding photophysical properties, facile tuning of structures and properties, and excellent photostability; thus, phototherapeutic agents based on organic small molecular DPP derivatives have attracted significant research attention for not only phototherapy but also photodiagnosis of fluorescence imaging (FLI) and photoacoustic imaging (PAI). This review summarizes the recent progress of various DPP-based organic small molecules on phototheranostics during the last five years. The molecular structure design and their phototheranostics performances are discussed in detail, as will be of great help for further creation of DPP-based phototheranostics.
Cancer is one of the leading causes of human death around the world. Phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), is an emerging light-triggered cancer treatment and shows the advantages of non-invasiveness and low side effects. The design and preparation of efficient phototherapeutic agents are of great significance for phototherapy. Diketopyrrolopyrrole (DPP) is a small molecular organic dye featuring outstanding photophysical properties, facile tuning of structures and properties, and excellent photostability; thus, phototherapeutic agents based on organic small molecular DPP derivatives have attracted significant research attention for not only phototherapy but also photodiagnosis of fluorescence imaging (FLI) and photoacoustic imaging (PAI). This review summarizes the recent progress of various DPP-based organic small molecules on phototheranostics during the last five years. The molecular structure design and their phototheranostics performances are discussed in detail, as will be of great help for further creation of DPP-based phototheranostics.
2022, 33(4): 1693-1704
doi: 10.1016/j.cclet.2021.11.050
Abstract:
miRNA, which is a common non-coding RNA, can target various mRNAs to regulate their physiological activities. Therefore, miRNAs play an important role in various physiological and pathological processes, and so they have been proposed as a powerful tool to treat different diseases efficiently. However, the characteristic of miRNA degradation in vivo limits its further clinical application. Exosomes have the advantage of crossing the biological barrier and achieving long-distance communication with cells, so they are excellent vectors for miRNAs. By studying the biogenesis of exosomes, the way for loading miRNAs, the mechanism of targeting, and disease occurrence and development, it is confirmed that exosomes can enrich specific endogenous miRNAs and regulate a variety of physiological activities, such as promoting cancer cell apoptosis, regulating lipid metabolism and promoting angiogenesis. It is shown that exosomes loaded with miRNAs have good performance in the fields of cancer, neurodegenerative diseases, cardiovascular disease treatment, and regenerative medicine. In this paper, the application and research progress of exosomes carrying miRNA in the above fields are systematically described.
miRNA, which is a common non-coding RNA, can target various mRNAs to regulate their physiological activities. Therefore, miRNAs play an important role in various physiological and pathological processes, and so they have been proposed as a powerful tool to treat different diseases efficiently. However, the characteristic of miRNA degradation in vivo limits its further clinical application. Exosomes have the advantage of crossing the biological barrier and achieving long-distance communication with cells, so they are excellent vectors for miRNAs. By studying the biogenesis of exosomes, the way for loading miRNAs, the mechanism of targeting, and disease occurrence and development, it is confirmed that exosomes can enrich specific endogenous miRNAs and regulate a variety of physiological activities, such as promoting cancer cell apoptosis, regulating lipid metabolism and promoting angiogenesis. It is shown that exosomes loaded with miRNAs have good performance in the fields of cancer, neurodegenerative diseases, cardiovascular disease treatment, and regenerative medicine. In this paper, the application and research progress of exosomes carrying miRNA in the above fields are systematically described.
2022, 33(4): 1705-1717
doi: 10.1016/j.cclet.2021.10.055
Abstract:
Atherosclerosis (AS), mainly caused by the changed immune system functions and inflammation, is the central pathogenesis of cardiovascular disease, which is a leading cause of death in the world. In modern medicine, the development of carriers precisely delivering the therapeutic agents to the target sites is the primary goal, which could minimize the potential adverse effects and be more effective in treating lesions. Due to the precise location, real-time monitoring, AS microenvironment response, and low toxicity, stimuli-responsive nano-based drug delivery systems (NDDSs) have been a promising approach in AS treatments. Herein, we will systematically summarize the recent advances in stimuli-responsive NDDSs for AS treatment, including internal stimuli (reactive oxygen species, enzyme, shear stress, and pH) and external stimuli (light, ultrasound, and magnetism) responsive NDDSs. Besides, we will also summarize in detail the classification of stimuli-responsive NDDSs for AS, such as organic NDDSs (e.g., lipid-based and polymer-based nanomaterials), inorganic NDDSs (e.g., metal-based nanoparticles and nonmetallic nanomaterials), and composite multifunctional NDDSs. Finally, the critical challenges and prospects of this field will also be proposed and discussed.
Atherosclerosis (AS), mainly caused by the changed immune system functions and inflammation, is the central pathogenesis of cardiovascular disease, which is a leading cause of death in the world. In modern medicine, the development of carriers precisely delivering the therapeutic agents to the target sites is the primary goal, which could minimize the potential adverse effects and be more effective in treating lesions. Due to the precise location, real-time monitoring, AS microenvironment response, and low toxicity, stimuli-responsive nano-based drug delivery systems (NDDSs) have been a promising approach in AS treatments. Herein, we will systematically summarize the recent advances in stimuli-responsive NDDSs for AS treatment, including internal stimuli (reactive oxygen species, enzyme, shear stress, and pH) and external stimuli (light, ultrasound, and magnetism) responsive NDDSs. Besides, we will also summarize in detail the classification of stimuli-responsive NDDSs for AS, such as organic NDDSs (e.g., lipid-based and polymer-based nanomaterials), inorganic NDDSs (e.g., metal-based nanoparticles and nonmetallic nanomaterials), and composite multifunctional NDDSs. Finally, the critical challenges and prospects of this field will also be proposed and discussed.
2022, 33(4): 1718-1728
doi: 10.1016/j.cclet.2021.10.074
Abstract:
Tumor immunotherapy, especially immune checkpoint blockade (ICB), has revolutionized the cancer field. However, the limited response of tumors to immunotherapy is a major obstacle. Tumor immunogenic cell death (ICD) is a death mode of tumor cells that can promote tumor immunity. ICD can induce strong antitumor immune responses through the ectopic exposure of calreticulin on the plasma membrane surface and the release of the non-histone nuclear protein high-mobility group box 1 (HMGB1), ATP, and interferon (IFN), thus activating an adaptive immune response against dead cell-associated antigens and enhancing the therapeutic effect of tumor immunotherapy. Chemotherapy, radiotherapy, photothermal therapy, magneto-thermodynamics therapy, nanopulse stimulation, and oncolytic virus therapy can all induce a strong antitumor immune response by ICD. In addition, the application of nanotechnology can precisely target drug delivery and improve the efficacy of immunotherapy. Here we introduce the basic concepts and molecular mechanisms underlying the induction of ICD. Then, we summarize and discuss the progress in the application of nanotechnology in immunotherapy to promote ICD. Finally, we attempt to define the challenges and future directions in this area to extend the benefits of ICD to a broader patient population.
Tumor immunotherapy, especially immune checkpoint blockade (ICB), has revolutionized the cancer field. However, the limited response of tumors to immunotherapy is a major obstacle. Tumor immunogenic cell death (ICD) is a death mode of tumor cells that can promote tumor immunity. ICD can induce strong antitumor immune responses through the ectopic exposure of calreticulin on the plasma membrane surface and the release of the non-histone nuclear protein high-mobility group box 1 (HMGB1), ATP, and interferon (IFN), thus activating an adaptive immune response against dead cell-associated antigens and enhancing the therapeutic effect of tumor immunotherapy. Chemotherapy, radiotherapy, photothermal therapy, magneto-thermodynamics therapy, nanopulse stimulation, and oncolytic virus therapy can all induce a strong antitumor immune response by ICD. In addition, the application of nanotechnology can precisely target drug delivery and improve the efficacy of immunotherapy. Here we introduce the basic concepts and molecular mechanisms underlying the induction of ICD. Then, we summarize and discuss the progress in the application of nanotechnology in immunotherapy to promote ICD. Finally, we attempt to define the challenges and future directions in this area to extend the benefits of ICD to a broader patient population.
2022, 33(4): 1729-1742
doi: 10.1016/j.cclet.2021.08.059
Abstract:
Advances in microbiology rely on innovations in technology. Droplet microfluidics, as a versatile and powerful technique that allows high-throughput generation and manipulation of subnanoliter volume droplets, has become an indispensable tool shifting experimental paradigms in microbiology. Droplet microfluidics has opened new avenues to various microbiological research, from resolving single-cell heterogeneity to investigating spatiotemporal dynamics of microbial communities, from precise quantitation of microbiota to systematic decipherment of microbial interactions, and from isolating rare and uncultured microbes to improving genetic engineered strains. In this review, we present recent advances of droplet microfluidics in various fields of microbiology: i) microbial cultivation, ii) microorganism detection and characterization, iii) antibiotic susceptibility testing, iv) microbial interactions, v) microbial biotechnology. We also provide our perspectives on the challenges and future directions for droplet microfluidic-based microbiology research.
Advances in microbiology rely on innovations in technology. Droplet microfluidics, as a versatile and powerful technique that allows high-throughput generation and manipulation of subnanoliter volume droplets, has become an indispensable tool shifting experimental paradigms in microbiology. Droplet microfluidics has opened new avenues to various microbiological research, from resolving single-cell heterogeneity to investigating spatiotemporal dynamics of microbial communities, from precise quantitation of microbiota to systematic decipherment of microbial interactions, and from isolating rare and uncultured microbes to improving genetic engineered strains. In this review, we present recent advances of droplet microfluidics in various fields of microbiology: i) microbial cultivation, ii) microorganism detection and characterization, iii) antibiotic susceptibility testing, iv) microbial interactions, v) microbial biotechnology. We also provide our perspectives on the challenges and future directions for droplet microfluidic-based microbiology research.
2022, 33(4): 1743-1751
doi: 10.1016/j.cclet.2021.08.073
Abstract:
Rapid on-site detection of pathogenic bacteria with high sensitivity and specificity is becoming an urgent need in public health assurance, medical diagnostics, environmental monitoring, and food safety fields. Despite being reliable and widely used, the existing methods of bacteria detection are cumbersome and time-consuming, which is not conducive to field detection. Microfluidic lab-on-a-chip technology has provided a detective tool for various analytes, due to its miniaturization, portability and low reagent consumption. Within this progress report, advances in the bacteria detection using microfluidic biosensors were discussed. Typical methods for pathogenic bacteria capture, separation and detection were introduced respectively in the first part. Then key applications of microfluidic biosensor-based rapid bacteria detection were presented. Finally, we made a conclusion and discussed possible research prospects in aspects of microfluidic biosensors for rapid detection of pathogenic bacteria.
Rapid on-site detection of pathogenic bacteria with high sensitivity and specificity is becoming an urgent need in public health assurance, medical diagnostics, environmental monitoring, and food safety fields. Despite being reliable and widely used, the existing methods of bacteria detection are cumbersome and time-consuming, which is not conducive to field detection. Microfluidic lab-on-a-chip technology has provided a detective tool for various analytes, due to its miniaturization, portability and low reagent consumption. Within this progress report, advances in the bacteria detection using microfluidic biosensors were discussed. Typical methods for pathogenic bacteria capture, separation and detection were introduced respectively in the first part. Then key applications of microfluidic biosensor-based rapid bacteria detection were presented. Finally, we made a conclusion and discussed possible research prospects in aspects of microfluidic biosensors for rapid detection of pathogenic bacteria.
2022, 33(4): 1752-1756
doi: 10.1016/j.cclet.2021.08.100
Abstract:
Living single-cell analysis is vital for cell biology, disease pathology, drug discovery and medical treatment. It is of great significance to reveal the law of creature and to explore the mechanism of serious disease. The conventional single cell analysis focuses on a large number of cells or cell lysis, in order to obtain the average information about cells. Therefore, it fails to analyze the real-time and continuous data of differences between the individual cells, thus limiting the development of many fields, such as biomedical. Nanofluidics based biochemical analysis exhibits advantages over conventional methods in terms of small sample volume, rapid turnaround time, straightforward operation, and efficient processing, which has been widely used in complex operations such as single cell capture, separation and single cell detection. Here we review the recent developments of nanofluidic technologies for single-cell analysis, with emphasis on cell trapping, treatment, and biochemical studies. The potential of nanofluidics-based single-cell analysis is discussed.
Living single-cell analysis is vital for cell biology, disease pathology, drug discovery and medical treatment. It is of great significance to reveal the law of creature and to explore the mechanism of serious disease. The conventional single cell analysis focuses on a large number of cells or cell lysis, in order to obtain the average information about cells. Therefore, it fails to analyze the real-time and continuous data of differences between the individual cells, thus limiting the development of many fields, such as biomedical. Nanofluidics based biochemical analysis exhibits advantages over conventional methods in terms of small sample volume, rapid turnaround time, straightforward operation, and efficient processing, which has been widely used in complex operations such as single cell capture, separation and single cell detection. Here we review the recent developments of nanofluidic technologies for single-cell analysis, with emphasis on cell trapping, treatment, and biochemical studies. The potential of nanofluidics-based single-cell analysis is discussed.
2022, 33(4): 1757-1762
doi: 10.1016/j.cclet.2021.08.091
Abstract:
To reduce greenhouse gas emission from oil and gas production, it is essential to better convert methane to useful chemicals (rather) than to flare it. Conversion of methane to liquid oxygenates (mainly methanol) has attracted extensive attention and countless efforts have been made; however, running this reaction in a green, efficient, and practical way has remained elusive. The novel catalyst and oxidants play a critical role in activating methane and converting it to oxygenates (methanol). In this review, the work of commonly used oxidants for methane partial oxidation have been summarized, in which, earth abundant oxidants, O2 and H2O are promising. Moreover, H2 or CO can activate O2 to produce H2O2 that catalyzes methane partial oxidation more efficiently and selectively than O2 or H2O. Therefore, the work of using reducing agent, such as CO and H2 have been reviewed, focusing on rational catalyst design that features multifunction (H2O2 production and CH4 activation). The novel catalyst design has advanced this reaction towards practicality with green oxidants and H2 using zeolites-based catalyst. Environmentally friendly zeolite preparation methods and novel two-dimensional (2D) zeolites that can reduce waste, improve synthesis and catalytical performance substantially are also reviewed in this work to provide insights for a more comprehensive approach to meet the environment protection needs.
To reduce greenhouse gas emission from oil and gas production, it is essential to better convert methane to useful chemicals (rather) than to flare it. Conversion of methane to liquid oxygenates (mainly methanol) has attracted extensive attention and countless efforts have been made; however, running this reaction in a green, efficient, and practical way has remained elusive. The novel catalyst and oxidants play a critical role in activating methane and converting it to oxygenates (methanol). In this review, the work of commonly used oxidants for methane partial oxidation have been summarized, in which, earth abundant oxidants, O2 and H2O are promising. Moreover, H2 or CO can activate O2 to produce H2O2 that catalyzes methane partial oxidation more efficiently and selectively than O2 or H2O. Therefore, the work of using reducing agent, such as CO and H2 have been reviewed, focusing on rational catalyst design that features multifunction (H2O2 production and CH4 activation). The novel catalyst design has advanced this reaction towards practicality with green oxidants and H2 using zeolites-based catalyst. Environmentally friendly zeolite preparation methods and novel two-dimensional (2D) zeolites that can reduce waste, improve synthesis and catalytical performance substantially are also reviewed in this work to provide insights for a more comprehensive approach to meet the environment protection needs.
2022, 33(4): 1763-1771
doi: 10.1016/j.cclet.2021.08.057
Abstract:
With the enhancement of the people consciousness of environment protection, soot particulates (PM) elimination has drawn wide attention in recent years. Efficient after-treatment with well-designed catalysts is one of the best ways to eliminate soot particulates that come from diesel engines. Catalysts coated on the DPF (diesel particulate filter) are considered as the main factor to lower soot ignition temperature. Improvement of the structures of the catalysts is significantly important in order to achieve good catalytic performance and high stability. Based on the structures, soot combustion catalysts can be mainly divided into three types: particle-based catalysts, 3DOM catalysts and nanoarray catalysts. This review mainly summarized recent advances in soot combustion catalysts with different designed micro-structures, each category is explained with critical assessment and several typical examples, aiming to guide the synthesis of advanced soot combustion catalysts.
With the enhancement of the people consciousness of environment protection, soot particulates (PM) elimination has drawn wide attention in recent years. Efficient after-treatment with well-designed catalysts is one of the best ways to eliminate soot particulates that come from diesel engines. Catalysts coated on the DPF (diesel particulate filter) are considered as the main factor to lower soot ignition temperature. Improvement of the structures of the catalysts is significantly important in order to achieve good catalytic performance and high stability. Based on the structures, soot combustion catalysts can be mainly divided into three types: particle-based catalysts, 3DOM catalysts and nanoarray catalysts. This review mainly summarized recent advances in soot combustion catalysts with different designed micro-structures, each category is explained with critical assessment and several typical examples, aiming to guide the synthesis of advanced soot combustion catalysts.
2022, 33(4): 1772-1778
doi: 10.1016/j.cclet.2021.08.055
Abstract:
Organic metal halide perovskite materials have excellent photoelectric properties, and the power conversion efficiency (PCE) of the perovskite solar cells (PSCs) has increased from 3.8% to more than 25%. In the development of PSCs, innovative architectures were being proposed constantly. However, the use of the electron transport layer (ETL) and hole transport layer (HTL) increases manufacturing costs and process complexity. Perovskite material has ambipolar charge transport characteristics, so it could functionalize as both the optical absorption layer and carrier transport layer (CTL). In this review, we analyzed the p/n-type perovskite materials, perovskite p-n homojunction solar cells, and carrier transport layers-free (CTLs-free) devices. Finally, we propose some innovative device architectures. We hope that this mini review could pave way for the simplification of the architectures, promote the preparation of the low-cost and high-efficiency devices, and accelerate the commercialization of the PSCs.
Organic metal halide perovskite materials have excellent photoelectric properties, and the power conversion efficiency (PCE) of the perovskite solar cells (PSCs) has increased from 3.8% to more than 25%. In the development of PSCs, innovative architectures were being proposed constantly. However, the use of the electron transport layer (ETL) and hole transport layer (HTL) increases manufacturing costs and process complexity. Perovskite material has ambipolar charge transport characteristics, so it could functionalize as both the optical absorption layer and carrier transport layer (CTL). In this review, we analyzed the p/n-type perovskite materials, perovskite p-n homojunction solar cells, and carrier transport layers-free (CTLs-free) devices. Finally, we propose some innovative device architectures. We hope that this mini review could pave way for the simplification of the architectures, promote the preparation of the low-cost and high-efficiency devices, and accelerate the commercialization of the PSCs.
2022, 33(4): 1779-1797
doi: 10.1016/j.cclet.2021.08.052
Abstract:
Molybdenum disulfide (MoS2), a typical two-dimensional transition metallic layered material, attracts tremendous attentions in the electrochemical energy storage due to its excellent physicochemical properties. However, with the deepening of the research and exploration of the lithium storage mechanism of these advanced MoS2-based anode materials, the complex reaction process influenced by internal and external factors hinders the exhaustive understanding of the lithium storage process. To design stable anode material with high performance, it is urgent to review the mechanisms of reported anode materials and summarize the related factors that influence the reaction processes. This review aims to dissect all possible side reactions during charging and discharging process, uncover internal and external factors inducing various anode reactions and finally put forward strategies of controlling high cycling capacity and super-stable lithium storage capability of MoS2. This review will be helpful to the design of MoS2-based lithium-ion batteries (LIBs) with excellent cycle performance to enlarge the application fields of these advanced electrochemical energy storage devices.
Molybdenum disulfide (MoS2), a typical two-dimensional transition metallic layered material, attracts tremendous attentions in the electrochemical energy storage due to its excellent physicochemical properties. However, with the deepening of the research and exploration of the lithium storage mechanism of these advanced MoS2-based anode materials, the complex reaction process influenced by internal and external factors hinders the exhaustive understanding of the lithium storage process. To design stable anode material with high performance, it is urgent to review the mechanisms of reported anode materials and summarize the related factors that influence the reaction processes. This review aims to dissect all possible side reactions during charging and discharging process, uncover internal and external factors inducing various anode reactions and finally put forward strategies of controlling high cycling capacity and super-stable lithium storage capability of MoS2. This review will be helpful to the design of MoS2-based lithium-ion batteries (LIBs) with excellent cycle performance to enlarge the application fields of these advanced electrochemical energy storage devices.
2022, 33(4): 1798-1816
doi: 10.1016/j.cclet.2021.09.068
Abstract:
The development of green and convenient methods for C–S bond formation has received significant attention because C–S bond widely occurs in many important pharmaceutical and biological compounds. Recently, visible-light photoredox catalysis has been established as an efficient and general tool for the construction of C–C and C-heteroatom bonds. In this review, we have focused on the research on recent advances in C–S bond formation via visible-light photoredox catalysis, and the growing opportunities they present to the construction of complex chemical scaffolds for applications encompassing bioactive molecules synthesis, synthetic methodology development, and sulfur-containing drugs. We hope that this review will provide chemists with a synthetic tool that will open the door to further development of organsulfur chemistry
The development of green and convenient methods for C–S bond formation has received significant attention because C–S bond widely occurs in many important pharmaceutical and biological compounds. Recently, visible-light photoredox catalysis has been established as an efficient and general tool for the construction of C–C and C-heteroatom bonds. In this review, we have focused on the research on recent advances in C–S bond formation via visible-light photoredox catalysis, and the growing opportunities they present to the construction of complex chemical scaffolds for applications encompassing bioactive molecules synthesis, synthetic methodology development, and sulfur-containing drugs. We hope that this review will provide chemists with a synthetic tool that will open the door to further development of organsulfur chemistry
2022, 33(4): 1817-1830
doi: 10.1016/j.cclet.2021.09.023
Abstract:
In order to fully replace the traditional fossil energy supply system, the efficiency of electrochemical energy conversion and storage of new energy technology needs to be continuously improved to enhance its market competitiveness. The structural design of energy devices can achieve satisfactory energy conversion and storage performance. To achieve lightweight design, improve mechanical support, enhance electrochemical performance, and adapt to the special shape of the device, the structural energy devices develop very quickly. To help researchers analyze the development and get clear on developing trend, this review is prepared. This review summarizes the latest developments in structural energy devices, including special attention to fuel cells, lithium-ion batteries, lithium metal batteries, and supercapacitors. Finally, the existing problems of structural energy devices are discussed, and the current challenges and future opportunities are summarized and prospected. Structural energy devices can undoubtedly overcome the performance bottlenecks of traditional energy devices, break the limitations of existing materials and structures, and provide a guidance for the development of equipment with high performance, light weight and low cost in the future.
In order to fully replace the traditional fossil energy supply system, the efficiency of electrochemical energy conversion and storage of new energy technology needs to be continuously improved to enhance its market competitiveness. The structural design of energy devices can achieve satisfactory energy conversion and storage performance. To achieve lightweight design, improve mechanical support, enhance electrochemical performance, and adapt to the special shape of the device, the structural energy devices develop very quickly. To help researchers analyze the development and get clear on developing trend, this review is prepared. This review summarizes the latest developments in structural energy devices, including special attention to fuel cells, lithium-ion batteries, lithium metal batteries, and supercapacitors. Finally, the existing problems of structural energy devices are discussed, and the current challenges and future opportunities are summarized and prospected. Structural energy devices can undoubtedly overcome the performance bottlenecks of traditional energy devices, break the limitations of existing materials and structures, and provide a guidance for the development of equipment with high performance, light weight and low cost in the future.
2022, 33(4): 1831-1840
doi: 10.1016/j.cclet.2021.09.034
Abstract:
Hydrogen energy could be a economic and powerful technology for sustainable future. Producing hydrogen fuel by electrochemical water splitting has attracted intense interest. Due to their physical and chemical properties, two-dimensional (2D) nanomaterials have sparked immense interest in water electrocatalysis for hydrogen production. This review focuses on the emerging nanocatalysts in 2D nanoarchitectures for electrocatalytic hydrogen production. The fundamentals of HER are firstly depicted, following the discussion of recent advances in typical 2D electrocatalysts for HER. The insights into the relationship among the synthetic protocols, structure, catalytic performance and thermodynamics will be discussed in details. Finally, the outlooks regarding further development of 2D nanocatalysts for HER are proposed. We hope this review will offer a comprehensive understanding in 2D nanocatalysts to promote electrochemical hydrogen production.
Hydrogen energy could be a economic and powerful technology for sustainable future. Producing hydrogen fuel by electrochemical water splitting has attracted intense interest. Due to their physical and chemical properties, two-dimensional (2D) nanomaterials have sparked immense interest in water electrocatalysis for hydrogen production. This review focuses on the emerging nanocatalysts in 2D nanoarchitectures for electrocatalytic hydrogen production. The fundamentals of HER are firstly depicted, following the discussion of recent advances in typical 2D electrocatalysts for HER. The insights into the relationship among the synthetic protocols, structure, catalytic performance and thermodynamics will be discussed in details. Finally, the outlooks regarding further development of 2D nanocatalysts for HER are proposed. We hope this review will offer a comprehensive understanding in 2D nanocatalysts to promote electrochemical hydrogen production.
2022, 33(4): 1841-1849
doi: 10.1016/j.cclet.2021.10.003
Abstract:
Dual specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) is an evolutionarily conserved protein kinase belonging to the CMGC kinase family, which is closely related to Down syndrome (DS) and Alzheimer's disease (AD). In recent years, not only the treatment of diabetes, but also the treatment of cancer gradually focuses on targeting DYRK1A. Therefore, a series of DYRK1A inhibitors have been developed to treat relevant diseases and clarify their treatment mechanism furtherly. DYRK1A inhibitors are mainly divided into natural products and synthetic compounds. Among them, harmine is an excellent DYRK1A inhibitor. Therefore, the synthetic DYRK1A inhibitors are mainly based on harmine, which greatly enriches the structure and quantity of DYRK1A inhibitors. The interaction between the inhibitors and the DYRK1A protein has a guiding significance in predicting the activity of the inhibitors, and plays an irreplaceable role in the design of the compounds. This paper mainly reviews DYRK1A inhibitors found in recent years and their structure-activity relationship, looking forward to providing a theoretical basis for the development of DYRK1A inhibitors.
Dual specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) is an evolutionarily conserved protein kinase belonging to the CMGC kinase family, which is closely related to Down syndrome (DS) and Alzheimer's disease (AD). In recent years, not only the treatment of diabetes, but also the treatment of cancer gradually focuses on targeting DYRK1A. Therefore, a series of DYRK1A inhibitors have been developed to treat relevant diseases and clarify their treatment mechanism furtherly. DYRK1A inhibitors are mainly divided into natural products and synthetic compounds. Among them, harmine is an excellent DYRK1A inhibitor. Therefore, the synthetic DYRK1A inhibitors are mainly based on harmine, which greatly enriches the structure and quantity of DYRK1A inhibitors. The interaction between the inhibitors and the DYRK1A protein has a guiding significance in predicting the activity of the inhibitors, and plays an irreplaceable role in the design of the compounds. This paper mainly reviews DYRK1A inhibitors found in recent years and their structure-activity relationship, looking forward to providing a theoretical basis for the development of DYRK1A inhibitors.
2022, 33(4): 1850-1854
doi: 10.1016/j.cclet.2021.11.020
Abstract:
Compared with other transition metal Mxene derived quantum dots (MQDS), Ta-based Mxene quantum dots have good functionality, but Ta-based Mxene quantum dots and their applications have not been studied so far. In this paper, we report for the first time the synthesis of high fluorescence quantum yield (QY) N-doped Ta4C3 quantum dots (N-MQDs) using Ta4C3 quantum dots in acid reflux damaged Ta4C3 nanosheets as precursors and ethylenediamine as nitrogen source. The prepared N-MQDs have excellent blue photoluminescence (PL) properties, particle size is only 2.60 nm, QY is up to 23.4%, and good stability. In addition, it has been reported that N-MQDs can be used as fluorescent probe for detection of Fe3+ and remote force sensing analysis In liquid ion sensing, N-MQDS shows a unique selective quenching of Fe3+ with a detection limit as low as 2 μmol/L, and has great potential as a fast and super-sensitive fluorescent probe for the detection of heavy ion. More importantly, in solid mechanics sensing, the introduction of N-MQDs into self-healing hydrogels can be developed into a fluorescent hydrogel that can be used for accurate remote force measurement and applied in the field of mechanical sensing analysis. Therefore, Ta-based N-MQDs show excellent potential in the field of fluorescence sensing, which provides a door for multi-dimensional sensing of new materials in the future.
Compared with other transition metal Mxene derived quantum dots (MQDS), Ta-based Mxene quantum dots have good functionality, but Ta-based Mxene quantum dots and their applications have not been studied so far. In this paper, we report for the first time the synthesis of high fluorescence quantum yield (QY) N-doped Ta4C3 quantum dots (N-MQDs) using Ta4C3 quantum dots in acid reflux damaged Ta4C3 nanosheets as precursors and ethylenediamine as nitrogen source. The prepared N-MQDs have excellent blue photoluminescence (PL) properties, particle size is only 2.60 nm, QY is up to 23.4%, and good stability. In addition, it has been reported that N-MQDs can be used as fluorescent probe for detection of Fe3+ and remote force sensing analysis In liquid ion sensing, N-MQDS shows a unique selective quenching of Fe3+ with a detection limit as low as 2 μmol/L, and has great potential as a fast and super-sensitive fluorescent probe for the detection of heavy ion. More importantly, in solid mechanics sensing, the introduction of N-MQDs into self-healing hydrogels can be developed into a fluorescent hydrogel that can be used for accurate remote force measurement and applied in the field of mechanical sensing analysis. Therefore, Ta-based N-MQDs show excellent potential in the field of fluorescence sensing, which provides a door for multi-dimensional sensing of new materials in the future.
2022, 33(4): 1855-1860
doi: 10.1016/j.cclet.2021.08.117
Abstract:
Rapid and accurate detection of immunoglobulin E (IgE) in serum and reduction of serum dosage are of great significance for clinical detection. Herein, we described a rapid magnetic separation of IgE from patient serum based on Fe3O4@SiO2-NTA@026 sdab as the capture probe and multiple horseradish peroxidase (HRP)-labeled antibodies linked gold nanoparticles (AuNPs) as chemiluminescence (CL) signal amplifier for ultrasensitive detection of total IgE. Results showed that the limit of detection of our immunosensor system in serum samples was 0.03 kU/L, which is lowest in comparison with current methods, and far lower than that of ImmunoCAP for IgE detection (0.1 kU/L). Furthermore, our immunosensor possessed satisfied repeatability and accuracy, as well as good stability. In comparison with the ImmunoCAP for the quantitative detection of IgE, highly consistent results were achieved in 20 serum samples. Specially, this method was also successfully utilized for assessing the IgE traces in breast cancer patients, which provides a new idea for the diagnosis of early cancer. Therefore, we believe that such versatile immunosensor will offer an alternative method for the on-site monitoring and determination of various IgE-related diseases.
Rapid and accurate detection of immunoglobulin E (IgE) in serum and reduction of serum dosage are of great significance for clinical detection. Herein, we described a rapid magnetic separation of IgE from patient serum based on Fe3O4@SiO2-NTA@026 sdab as the capture probe and multiple horseradish peroxidase (HRP)-labeled antibodies linked gold nanoparticles (AuNPs) as chemiluminescence (CL) signal amplifier for ultrasensitive detection of total IgE. Results showed that the limit of detection of our immunosensor system in serum samples was 0.03 kU/L, which is lowest in comparison with current methods, and far lower than that of ImmunoCAP for IgE detection (0.1 kU/L). Furthermore, our immunosensor possessed satisfied repeatability and accuracy, as well as good stability. In comparison with the ImmunoCAP for the quantitative detection of IgE, highly consistent results were achieved in 20 serum samples. Specially, this method was also successfully utilized for assessing the IgE traces in breast cancer patients, which provides a new idea for the diagnosis of early cancer. Therefore, we believe that such versatile immunosensor will offer an alternative method for the on-site monitoring and determination of various IgE-related diseases.
2022, 33(4): 1861-1864
doi: 10.1016/j.cclet.2021.10.024
Abstract:
Excessive mercury ions (Hg2+) in the environment can accumulate in human body along with the food chain to cause serious physiological reactions. The fluorescence probes were considered as convenient tool with great potential for Hg2+ detection. Most existing probes suffer from aggregation-induced quenching (ACQ) effects and insufficient sensitivity. Herein, a novel type of fluorophore was developed by combining the aggregation-induced emission (AIE) and excited state intramolecular proton transfer (ESIPT) characteristics. Subsequently, a phenyl thioformate group with photoinduced electron transfer (PET) effect was connected to give an efficient "turn-on" probe (HTM), which exhibited good selectivity toward Hg2+, short response time (30 min), coupled with extremely low detection limit (LOD = 1.68 nmol/L). In addition, HTM was used successfully in real samples, cells and drug evaluation, underlying the superiority of HTM to detect Hg2+ in practical applications.
Excessive mercury ions (Hg2+) in the environment can accumulate in human body along with the food chain to cause serious physiological reactions. The fluorescence probes were considered as convenient tool with great potential for Hg2+ detection. Most existing probes suffer from aggregation-induced quenching (ACQ) effects and insufficient sensitivity. Herein, a novel type of fluorophore was developed by combining the aggregation-induced emission (AIE) and excited state intramolecular proton transfer (ESIPT) characteristics. Subsequently, a phenyl thioformate group with photoinduced electron transfer (PET) effect was connected to give an efficient "turn-on" probe (HTM), which exhibited good selectivity toward Hg2+, short response time (30 min), coupled with extremely low detection limit (LOD = 1.68 nmol/L). In addition, HTM was used successfully in real samples, cells and drug evaluation, underlying the superiority of HTM to detect Hg2+ in practical applications.
2022, 33(4): 1865-1869
doi: 10.1016/j.cclet.2021.10.025
Abstract:
Theranostic visualization of dextran at the nanoscale is beneficial for understanding the bioregulatory mechanisms of this molecule. In this study, we applied structured illumination microscopy (SIM) to capture the distribution of Cy5-Dextran at different incubation periods in living cells. The results showed that Cy5-Dextran could be absorbed by HeLa cells. In addition, we clarified that Cy5-Dextran exhibited differential organelle distribution (lysosomal or mitochondrial) in a time-dependent manner. Moreover, lysosomal Cy5-Dextran localization was found to be independent of the autophagy process, while Cy5-Dextran localized to the mitochondria triggered a pro-apoptotic event, upregulating the levels of reactive oxygen species (ROS) to accelerate mitochondrial fragmentation. This work uses a visualized strategy to reveal the anti-tumor bioactivity of dextran, which was achieved by regulating apoptosis and autophagy.
Theranostic visualization of dextran at the nanoscale is beneficial for understanding the bioregulatory mechanisms of this molecule. In this study, we applied structured illumination microscopy (SIM) to capture the distribution of Cy5-Dextran at different incubation periods in living cells. The results showed that Cy5-Dextran could be absorbed by HeLa cells. In addition, we clarified that Cy5-Dextran exhibited differential organelle distribution (lysosomal or mitochondrial) in a time-dependent manner. Moreover, lysosomal Cy5-Dextran localization was found to be independent of the autophagy process, while Cy5-Dextran localized to the mitochondria triggered a pro-apoptotic event, upregulating the levels of reactive oxygen species (ROS) to accelerate mitochondrial fragmentation. This work uses a visualized strategy to reveal the anti-tumor bioactivity of dextran, which was achieved by regulating apoptosis and autophagy.
2022, 33(4): 1870-1874
doi: 10.1016/j.cclet.2021.11.054
Abstract:
Triphenylamine (TPA) derivatives have been widely used as useful building blocks for diverse functional materials because of their excellent redox activity. Most of the molecular structures of TPA-based organic functional materials contain 4-anisyl groups, which on one hand could reduce their oxidation potential and on the other hand significantly delocalize the spin density of the resultant TPA radical cation species and enhance their stability. However, molecular-level investigation of the redox behavior of triphenylamines consisting of 4-anisyl group and the electronic structures of their radical cation species has not been reported in the literature. Herein, we design a series of triphenylamines consisting of one, two, or three 3, 5-di-tert-butyl-4-anisyl groups and investigate their redox behaviors and corresponding radical cation species. We disclose that the resonance hybrid and steric protection could both contribute to the stability of triphenylamine radical cations. Moreover, further oxidation leads to an unexpected oxidative demethylation. The findings in this work may reveal new insights for the understanding of the unique redox properties of 4-anisyl substituted triphenylamines.
Triphenylamine (TPA) derivatives have been widely used as useful building blocks for diverse functional materials because of their excellent redox activity. Most of the molecular structures of TPA-based organic functional materials contain 4-anisyl groups, which on one hand could reduce their oxidation potential and on the other hand significantly delocalize the spin density of the resultant TPA radical cation species and enhance their stability. However, molecular-level investigation of the redox behavior of triphenylamines consisting of 4-anisyl group and the electronic structures of their radical cation species has not been reported in the literature. Herein, we design a series of triphenylamines consisting of one, two, or three 3, 5-di-tert-butyl-4-anisyl groups and investigate their redox behaviors and corresponding radical cation species. We disclose that the resonance hybrid and steric protection could both contribute to the stability of triphenylamine radical cations. Moreover, further oxidation leads to an unexpected oxidative demethylation. The findings in this work may reveal new insights for the understanding of the unique redox properties of 4-anisyl substituted triphenylamines.
2022, 33(4): 1875-1879
doi: 10.1016/j.cclet.2021.10.077
Abstract:
Platinum-based anticancer agents such as cisplatin and its analogues are widely used for treating multiple cancers. However, due to the inferior water-solubility, chemoresistance and consequent adverse side effects, their clinical applications are limited. Herein, cholesPt(IV), a lipophilic platinum(IV) prodrug was synthesized for manufacture of CholesPt(IV)-Liposomes aiming to resolve the predefined obstacles encountered by platinum drugs. Following systematic screening, CholesPt(IV)-Liposomes showed a small particle size (105.6 nm), the rapid release of platinum (Pt) ions, and notable apoptosis of cancer cells. In addition, according to the fluidity and safety results of animal experiments in mice, CholesPt(IV)-Liposomes also showed better therapeutic effect, which significantly inhibited the growth of patient-derived xenograft tumors of hepatocellular carcinoma with an inhibition ratio of 80.7%, and effectively alleviated the drug toxicity brought by traditional platinum drugs. Overall, this study provides a promising route to enhance the therapeutic efficiency of platinum drugs in cancer treatment.
Platinum-based anticancer agents such as cisplatin and its analogues are widely used for treating multiple cancers. However, due to the inferior water-solubility, chemoresistance and consequent adverse side effects, their clinical applications are limited. Herein, cholesPt(IV), a lipophilic platinum(IV) prodrug was synthesized for manufacture of CholesPt(IV)-Liposomes aiming to resolve the predefined obstacles encountered by platinum drugs. Following systematic screening, CholesPt(IV)-Liposomes showed a small particle size (105.6 nm), the rapid release of platinum (Pt) ions, and notable apoptosis of cancer cells. In addition, according to the fluidity and safety results of animal experiments in mice, CholesPt(IV)-Liposomes also showed better therapeutic effect, which significantly inhibited the growth of patient-derived xenograft tumors of hepatocellular carcinoma with an inhibition ratio of 80.7%, and effectively alleviated the drug toxicity brought by traditional platinum drugs. Overall, this study provides a promising route to enhance the therapeutic efficiency of platinum drugs in cancer treatment.
2022, 33(4): 1880-1884
doi: 10.1016/j.cclet.2021.10.022
Abstract:
Nowadays, there are still many challenges to skin regeneration. As a new type of skin substitute, hydrogel has emerging gradually with its excellent properties. However, it is still a challenge to combine with biological active agents to facilitate skin regeneration. Under the circumstance, we synthesized arginine-based poly(ester amide) (Arg-PEA) and hyaluronic acid (HA-MA), and combined them into new hybrid hydrogels via photo-crosslinking. We found that the internal structure and physicochemical properties of hybrid hydrogels were greatly improved with the increase of content of Arg-PEA. Therefore, we designed hybrid hydrogels with 5 wt% and 10 wt% of Arg-PEA content, respectively. Besides, we selected the corresponding anti-inflammatory (CRP, TNF-α) indicators to detect the anti-inflammatory properties of the hybrid hydrogels at the protein level, and the corresponding antioxidant indicators (SOD, GSH/GSSG, MDA) were selected to investigate the antioxidant properties of hybrid hydrogels at the cellular level in vitro. In addition, we also selected relevant genes to test the effect of hybrid hydrogels on fibrosis and vascularization in the process of skin wound healing in vitro and verified them in vivo with a mouse dorsum wound model. The results confirmed that Arg-PEA/HA-MA (AH) hybrid hydrogel was a prospective scaffold material for skin regeneration.
Nowadays, there are still many challenges to skin regeneration. As a new type of skin substitute, hydrogel has emerging gradually with its excellent properties. However, it is still a challenge to combine with biological active agents to facilitate skin regeneration. Under the circumstance, we synthesized arginine-based poly(ester amide) (Arg-PEA) and hyaluronic acid (HA-MA), and combined them into new hybrid hydrogels via photo-crosslinking. We found that the internal structure and physicochemical properties of hybrid hydrogels were greatly improved with the increase of content of Arg-PEA. Therefore, we designed hybrid hydrogels with 5 wt% and 10 wt% of Arg-PEA content, respectively. Besides, we selected the corresponding anti-inflammatory (CRP, TNF-α) indicators to detect the anti-inflammatory properties of the hybrid hydrogels at the protein level, and the corresponding antioxidant indicators (SOD, GSH/GSSG, MDA) were selected to investigate the antioxidant properties of hybrid hydrogels at the cellular level in vitro. In addition, we also selected relevant genes to test the effect of hybrid hydrogels on fibrosis and vascularization in the process of skin wound healing in vitro and verified them in vivo with a mouse dorsum wound model. The results confirmed that Arg-PEA/HA-MA (AH) hybrid hydrogel was a prospective scaffold material for skin regeneration.
2022, 33(4): 1885-1888
doi: 10.1016/j.cclet.2021.09.044
Abstract:
The rapid detection of microparticles exhibits a broad range of applications in the field of science and technology. The proposed method differentiates and identifies the 2 µm and 5 µm sized particles using a laser light scattering. The detection method is based on measuring forward light scattering from the particles and then classifying the acquired data using support vector machines. The device is composed of a microfluidic chip linked with photosensors and a laser device using optical fiber. Connecting the photosensors and laser device using optical fibers makes the device more diminutive in size and portable. The prepared sample containing microspheres was passed through the channel, and the surrounding photosensors measured the scattered light. The time-domain features were evaluated from the acquired scattered light, and then the SVM classifier was trained to distinguish the particle's data. The real-time detection of the particles was performed with an overall classification accuracy of 96.06%. The optimum conditions were evaluated to detect the particles with a minimum concentration of 0.2 µg/mL. The developed system is anticipated to be helpful in developing rapid testing devices for detecting pathogens ranging between 2 µm to 10 µm.
The rapid detection of microparticles exhibits a broad range of applications in the field of science and technology. The proposed method differentiates and identifies the 2 µm and 5 µm sized particles using a laser light scattering. The detection method is based on measuring forward light scattering from the particles and then classifying the acquired data using support vector machines. The device is composed of a microfluidic chip linked with photosensors and a laser device using optical fiber. Connecting the photosensors and laser device using optical fibers makes the device more diminutive in size and portable. The prepared sample containing microspheres was passed through the channel, and the surrounding photosensors measured the scattered light. The time-domain features were evaluated from the acquired scattered light, and then the SVM classifier was trained to distinguish the particle's data. The real-time detection of the particles was performed with an overall classification accuracy of 96.06%. The optimum conditions were evaluated to detect the particles with a minimum concentration of 0.2 µg/mL. The developed system is anticipated to be helpful in developing rapid testing devices for detecting pathogens ranging between 2 µm to 10 µm.
2022, 33(4): 1889-1894
doi: 10.1016/j.cclet.2021.10.023
Abstract:
Permeation enhancers (PEs), such as N-[8-(2-hydroxybenzoyl)amino]-caprylate (SNAC), have been reported to improve the oral absorption of various macromolecules. However, the bioavailabilities of these formulations are quite low and variable due to the influences of enzymes, pH and other gastrointestinal barriers. In this study, we revealed that SNAC could interact with insulin to form tight complexes in a specific concentration (insulin ≥ 40 µg/mL)-, ratio (SNAC/insulin ≥ 20:1)- and pH (≥ 6.8)-dependent manner, thus contributing to a significantly high efficacy of oral insulin delivery. Specifically, absorption mechanism studies revealed that the SNAC/insulin complexes were internalized into the cells by passive diffusion and remained intact when transported in the cytosol. Furthermore, the complexes accelerated the exocytosis of insulin to the basolateral side, thereby enhancing its intestinal mucosal permeability. Eudragit® S100-entrapped SNAC/insulin microspheres were then prepared and exhibited an apparent permeability coefficient (Papp) that was 6.6-fold higher than that of the insulin solution. In diabetic rats, hypoglycemic activity was sustained for more than 10 h after the microspheres were loaded into enteric-coated capsules. Further pharmacokinetic studies revealed an approximately 6.3% oral bioavailability in both the fasted and fed states, indicating a negligible food effect. Collectively, this study provides insight into the interaction between PEs and payloads and presents an SNAC-based oral insulin delivery system that has high oral bioavailability and patient-friendly medication guidance.
Permeation enhancers (PEs), such as N-[8-(2-hydroxybenzoyl)amino]-caprylate (SNAC), have been reported to improve the oral absorption of various macromolecules. However, the bioavailabilities of these formulations are quite low and variable due to the influences of enzymes, pH and other gastrointestinal barriers. In this study, we revealed that SNAC could interact with insulin to form tight complexes in a specific concentration (insulin ≥ 40 µg/mL)-, ratio (SNAC/insulin ≥ 20:1)- and pH (≥ 6.8)-dependent manner, thus contributing to a significantly high efficacy of oral insulin delivery. Specifically, absorption mechanism studies revealed that the SNAC/insulin complexes were internalized into the cells by passive diffusion and remained intact when transported in the cytosol. Furthermore, the complexes accelerated the exocytosis of insulin to the basolateral side, thereby enhancing its intestinal mucosal permeability. Eudragit® S100-entrapped SNAC/insulin microspheres were then prepared and exhibited an apparent permeability coefficient (Papp) that was 6.6-fold higher than that of the insulin solution. In diabetic rats, hypoglycemic activity was sustained for more than 10 h after the microspheres were loaded into enteric-coated capsules. Further pharmacokinetic studies revealed an approximately 6.3% oral bioavailability in both the fasted and fed states, indicating a negligible food effect. Collectively, this study provides insight into the interaction between PEs and payloads and presents an SNAC-based oral insulin delivery system that has high oral bioavailability and patient-friendly medication guidance.
2022, 33(4): 1895-1900
doi: 10.1016/j.cclet.2021.10.021
Abstract:
Ferroustherapy has gained great attention for anti-cancer treatment in recent years. Enlightened by temperature-mediated Fenton reaction in industrial waste water removal, we designed a iron-based polyphenol-coordinated nanomedicines for mild hyperthermia-assisted anti-cancer ferroustherapy. In brief, Fe-GA@BSA nanoparticles was synthesized by self-assembly and sorafenib (SRF) was loaded into Fe-GA@BSA to establish Fe-GA@BSA-SRF nanomedicines. The result nanomedicines can induce ferroptosis in cancer cells by accelerating Fenton reaction. And the photothermal effect of Fe-GA@BSA-SRF was used for mild hyperthermia-assisted ferroustherapy. The nanomedicines performs good anti-cancer therapeutic efficacy by inducing the production of ROS and inhibiting glutathione peroxidase 4 (GPX4) expression in vitro and in vivo. Besides, the broad absorption of Fe-GA@BSA-SRF in near infrared region endows it with photoacoustic imaging ability. This study provides ideas about rational design on iron-based nanoparticles for anti-cancer ferroustherapy.
Ferroustherapy has gained great attention for anti-cancer treatment in recent years. Enlightened by temperature-mediated Fenton reaction in industrial waste water removal, we designed a iron-based polyphenol-coordinated nanomedicines for mild hyperthermia-assisted anti-cancer ferroustherapy. In brief, Fe-GA@BSA nanoparticles was synthesized by self-assembly and sorafenib (SRF) was loaded into Fe-GA@BSA to establish Fe-GA@BSA-SRF nanomedicines. The result nanomedicines can induce ferroptosis in cancer cells by accelerating Fenton reaction. And the photothermal effect of Fe-GA@BSA-SRF was used for mild hyperthermia-assisted ferroustherapy. The nanomedicines performs good anti-cancer therapeutic efficacy by inducing the production of ROS and inhibiting glutathione peroxidase 4 (GPX4) expression in vitro and in vivo. Besides, the broad absorption of Fe-GA@BSA-SRF in near infrared region endows it with photoacoustic imaging ability. This study provides ideas about rational design on iron-based nanoparticles for anti-cancer ferroustherapy.
2022, 33(4): 1901-1906
doi: 10.1016/j.cclet.2021.10.029
Abstract:
Neuroinflammation plays a significant role in inducing depression-like behavior. Tetrahedral DNA nanostructures (TDNs) are molecules that exhibit anti-inflammatory properties and can effectively penetrate the blood-brain barrier. Thus, researchers have hypothesized that TDNs regulate the secretion of proinflammatory cytokines and consequently alleviate depression-like behavior. To test this hypothesis, we investigated the effect of TDNs on the depression-like behavior of C57 mice induced by lipopolysaccharide (LPS). We performed open-field, tail suspension, and sucrose preference tests on LPS- and LPS/TDN-treated mice. The results indicated that the injection of TDNs into LPS-treated mice resulted in increased velocity, center zone duration, frequency to the center zone, and sucrose preference, and decreased immobility time. Immunofluorescence results indicated that peripheral administration of LPS in the mice activated inflammation, which culminated in distinct depression-like behavior. However, TDNs effectively alleviated the inflammation and depression-like behavior through the reduction of the expression levels of proinflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α in the brain. Additionally, TDNs normalized the expression level of microglia cell activation markers, such as ionized calcium binding adaptor molecule 1, in the hippocampus of mice. These results indicated that TDNs attenuated the LPS-induced secretion of inflammatory factors and consequently alleviated depression-like behavior.
Neuroinflammation plays a significant role in inducing depression-like behavior. Tetrahedral DNA nanostructures (TDNs) are molecules that exhibit anti-inflammatory properties and can effectively penetrate the blood-brain barrier. Thus, researchers have hypothesized that TDNs regulate the secretion of proinflammatory cytokines and consequently alleviate depression-like behavior. To test this hypothesis, we investigated the effect of TDNs on the depression-like behavior of C57 mice induced by lipopolysaccharide (LPS). We performed open-field, tail suspension, and sucrose preference tests on LPS- and LPS/TDN-treated mice. The results indicated that the injection of TDNs into LPS-treated mice resulted in increased velocity, center zone duration, frequency to the center zone, and sucrose preference, and decreased immobility time. Immunofluorescence results indicated that peripheral administration of LPS in the mice activated inflammation, which culminated in distinct depression-like behavior. However, TDNs effectively alleviated the inflammation and depression-like behavior through the reduction of the expression levels of proinflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α in the brain. Additionally, TDNs normalized the expression level of microglia cell activation markers, such as ionized calcium binding adaptor molecule 1, in the hippocampus of mice. These results indicated that TDNs attenuated the LPS-induced secretion of inflammatory factors and consequently alleviated depression-like behavior.
2022, 33(4): 1907-1912
doi: 10.1016/j.cclet.2021.11.017
Abstract:
Metal-based compounds with excellent photo-physical properties show good photochemotherapeutic performance. But, low in-depth tissue penetration of light limits their effectivity for deeply buried tumors. Encouraged by the sonosensitizing ability of the traditional organic photosensitizers, here, we developed AuNPs@Ir1 as a sonosensitizer by hybridizing an organometallic Ir(Ⅲ) complex (Ir1) with ultrasmall gold nanoparticles (AuNPs) for efficient tumor sonodynamic therapy (SDT) for the first time. AuNPs@Ir1 rapidly entered the cancer cells, produced 1O2, and catalytically oxidized NADH to NAD+ under ultrasound (US) irradiation, thus resulted in cancer cells oncosis. Because of efficient passive retention in tumors post intravenous injection, AuNPs@Ir1 further efficiently inhibited the growth of tumors in-vivo under US stimulation without long-term toxicity to other organs. Overall, this work presents the excellent US triggered in-vitro and in-vivo anticancer profile of the novel AuNPs@Ir1. It is expected to increase the scope of SDT for metal-based anticancer drugs.
Metal-based compounds with excellent photo-physical properties show good photochemotherapeutic performance. But, low in-depth tissue penetration of light limits their effectivity for deeply buried tumors. Encouraged by the sonosensitizing ability of the traditional organic photosensitizers, here, we developed AuNPs@Ir1 as a sonosensitizer by hybridizing an organometallic Ir(Ⅲ) complex (Ir1) with ultrasmall gold nanoparticles (AuNPs) for efficient tumor sonodynamic therapy (SDT) for the first time. AuNPs@Ir1 rapidly entered the cancer cells, produced 1O2, and catalytically oxidized NADH to NAD+ under ultrasound (US) irradiation, thus resulted in cancer cells oncosis. Because of efficient passive retention in tumors post intravenous injection, AuNPs@Ir1 further efficiently inhibited the growth of tumors in-vivo under US stimulation without long-term toxicity to other organs. Overall, this work presents the excellent US triggered in-vitro and in-vivo anticancer profile of the novel AuNPs@Ir1. It is expected to increase the scope of SDT for metal-based anticancer drugs.
2022, 33(4): 1913-1916
doi: 10.1016/j.cclet.2021.11.025
Abstract:
In this work, a simple gold nanoparticles (AuNPs) based colorimetric biosensor was developed for chlorpyrifos (Chl) detection using an aptamer as the capture probe. The Chl-aptamer with low dissociation constant (Kd) of 58.59 ± 6.08 nmol/L was selected by ssDNA library immobilized systematic evolution of ligands by enrichment (SELEX). In the absence of Chl, the Chl-aptamer acted as the stabilizer for AuNPs in salt solution. In the presence of Chl, the highly specific Chl-aptamer bound with Chl targets immediately, thus a self-aggregation of AuNPs induced by salt was displayed. The fabricated colorimetric aptasensor exhibited an excellent sensitivity for Chl detection with the LOD as low as 14.46 nmol/L. In addition, the aptasensor was applied to test Chl in tap water, cucumber and cabbage samples, the excellent recoveries with acceptable RSD values below 5% demonstrated that the method can be considered as a promising tool for simple, rapid Chl detection.
In this work, a simple gold nanoparticles (AuNPs) based colorimetric biosensor was developed for chlorpyrifos (Chl) detection using an aptamer as the capture probe. The Chl-aptamer with low dissociation constant (Kd) of 58.59 ± 6.08 nmol/L was selected by ssDNA library immobilized systematic evolution of ligands by enrichment (SELEX). In the absence of Chl, the Chl-aptamer acted as the stabilizer for AuNPs in salt solution. In the presence of Chl, the highly specific Chl-aptamer bound with Chl targets immediately, thus a self-aggregation of AuNPs induced by salt was displayed. The fabricated colorimetric aptasensor exhibited an excellent sensitivity for Chl detection with the LOD as low as 14.46 nmol/L. In addition, the aptasensor was applied to test Chl in tap water, cucumber and cabbage samples, the excellent recoveries with acceptable RSD values below 5% demonstrated that the method can be considered as a promising tool for simple, rapid Chl detection.
2022, 33(4): 1917-1922
doi: 10.1016/j.cclet.2021.11.040
Abstract:
The intrinsic hypoxic tumor microenvironment and limited accumulation of photosensitizers (PSs) result in unsatisfied efficiency of photodynamic therapy (PDT). To enhance the PDT efficiency against solid tumors, a functional oxygen self-supplying and PS-delivering nanosystem is fabricated via the combination of catalase (CAT), chlorin e6 (Ce6) and metal-phenolic network (MPN) capsule. It is demonstrated that the CAT encapsulated in the capsules (named CCM capsules) could catalyze the degradation of hydrogen peroxide (H2O2) to produce molecular oxygen (O2), which could be converted into cytotoxicity reactive oxygen species (ROS) by surface-loaded Ce6 under 660 nm laser irradiation, leading to synergistic anticancer effects in vitro and in vivo. Therefore, the application of CCM capsule could be a promising strategy to improve PDT effectiveness.
The intrinsic hypoxic tumor microenvironment and limited accumulation of photosensitizers (PSs) result in unsatisfied efficiency of photodynamic therapy (PDT). To enhance the PDT efficiency against solid tumors, a functional oxygen self-supplying and PS-delivering nanosystem is fabricated via the combination of catalase (CAT), chlorin e6 (Ce6) and metal-phenolic network (MPN) capsule. It is demonstrated that the CAT encapsulated in the capsules (named CCM capsules) could catalyze the degradation of hydrogen peroxide (H2O2) to produce molecular oxygen (O2), which could be converted into cytotoxicity reactive oxygen species (ROS) by surface-loaded Ce6 under 660 nm laser irradiation, leading to synergistic anticancer effects in vitro and in vivo. Therefore, the application of CCM capsule could be a promising strategy to improve PDT effectiveness.
2022, 33(4): 1923-1926
doi: 10.1016/j.cclet.2021.11.039
Abstract:
Light-responsive carriers have been used for the controlled release of antitumor drugs in recent years. However, most light-responsive vectors require high-energy ultraviolet or visible light to achieve local drug release, and ultraviolet light would cause cellular damage. Near-infrared light has a deeper tissue-penetration depths and minimal harm to tissues, but it is difficult to cleave the chemical bond directly. The aim of this study is to develop a novel near-infrared light-responsive carrier for local release of antitumor drugs. Unsaturated phospholipids can be oxidized by singlet oxygen to achieve liposomal drug release, and singlet oxygen can be produced by photosensitizer under light irradiation. A new near-infrared light-responsive nanoliposome was designed that imparts light-triggered local drug release. Nanoliposomes, which were composed of matrix phospholipids and unsaturated phospholipids, were prepared by ammonium sulfate gradient method, and loaded with antitumor drug doxorubicin (DOX) and photosensitizer 1, 4, 8, 11, 15, 18, 22, 25-octabutoxypalladium phthalocyanine. Under near-infrared light, photosensitizers could produce singlet oxygen and damage tumor cells by photodynamic therapy. Simultaneously, the unsaturated phospholipids were oxidized by singlet oxygen and result in DOX release, causing sustained cell damage by chemotherapy. Near-infrared light-responsive nanoliposomes exhibit enhanced anticancer activity owing to combined treatment of photodynamic therapy and chemotherapy. A new platform is thus offered for designing effective intracellular drug-release systems, holding great promise for future cancer therapy.
Light-responsive carriers have been used for the controlled release of antitumor drugs in recent years. However, most light-responsive vectors require high-energy ultraviolet or visible light to achieve local drug release, and ultraviolet light would cause cellular damage. Near-infrared light has a deeper tissue-penetration depths and minimal harm to tissues, but it is difficult to cleave the chemical bond directly. The aim of this study is to develop a novel near-infrared light-responsive carrier for local release of antitumor drugs. Unsaturated phospholipids can be oxidized by singlet oxygen to achieve liposomal drug release, and singlet oxygen can be produced by photosensitizer under light irradiation. A new near-infrared light-responsive nanoliposome was designed that imparts light-triggered local drug release. Nanoliposomes, which were composed of matrix phospholipids and unsaturated phospholipids, were prepared by ammonium sulfate gradient method, and loaded with antitumor drug doxorubicin (DOX) and photosensitizer 1, 4, 8, 11, 15, 18, 22, 25-octabutoxypalladium phthalocyanine. Under near-infrared light, photosensitizers could produce singlet oxygen and damage tumor cells by photodynamic therapy. Simultaneously, the unsaturated phospholipids were oxidized by singlet oxygen and result in DOX release, causing sustained cell damage by chemotherapy. Near-infrared light-responsive nanoliposomes exhibit enhanced anticancer activity owing to combined treatment of photodynamic therapy and chemotherapy. A new platform is thus offered for designing effective intracellular drug-release systems, holding great promise for future cancer therapy.
2022, 33(4): 1927-1932
doi: 10.1016/j.cclet.2021.11.056
Abstract:
Photodynamic therapy (PDT) has been widely investigated for cancer therapy. The intracellular accumulation of reactive oxygen species (ROS)-damaged protein facilitates tumor cell apoptosis. However, there is growing evidence that the ubiquitin-proteasome pathway (UPP) significantly impedes PDT by preventing the enrichment of ROS-damaged proteins in tumor cells. To tackle this challenge, we report a facile dual-drug nanoassembly based on the discovery of an interesting co-assembly of bortezomib (BTZ, a proteasome inhibitor) and pyropheophorbide a (PPa) for proteasome inhibition-mediated PDT sensitization. The precisely engineered nanoassembly with the optimal dose ratio of BTZ and PPa demonstrates multiple advantages, including simple fabrication, high drug co-loading efficiency, flexible dose adjustment, good colloidal stability, long systemic circulation, favorable tumor-specific accumulation, as well as significant enrichment of ROS-damaged proteins in tumor cells. As a result, the cooperative nanoassembly exhibits potent synergistic antitumor activity in vivo. This study provides a novel dual-drug engineering modality for multimodal cancer treatment.
Photodynamic therapy (PDT) has been widely investigated for cancer therapy. The intracellular accumulation of reactive oxygen species (ROS)-damaged protein facilitates tumor cell apoptosis. However, there is growing evidence that the ubiquitin-proteasome pathway (UPP) significantly impedes PDT by preventing the enrichment of ROS-damaged proteins in tumor cells. To tackle this challenge, we report a facile dual-drug nanoassembly based on the discovery of an interesting co-assembly of bortezomib (BTZ, a proteasome inhibitor) and pyropheophorbide a (PPa) for proteasome inhibition-mediated PDT sensitization. The precisely engineered nanoassembly with the optimal dose ratio of BTZ and PPa demonstrates multiple advantages, including simple fabrication, high drug co-loading efficiency, flexible dose adjustment, good colloidal stability, long systemic circulation, favorable tumor-specific accumulation, as well as significant enrichment of ROS-damaged proteins in tumor cells. As a result, the cooperative nanoassembly exhibits potent synergistic antitumor activity in vivo. This study provides a novel dual-drug engineering modality for multimodal cancer treatment.
2022, 33(4): 1933-1935
doi: 10.1016/j.cclet.2021.11.051
Abstract:
Listeriosis is caused by Listeria monocytogenes (LM) and is currently considered to be one of the leading food-borne diseases worldwide, with mortality rate of 20%~30%. Currently, detection methods for LM are time-consuming with low sensitivity, and delayed detection results. SYTO9 has a high affinity for DNA and exhibits enhanced fluorescence upon binding. Therefore, this study used SYTO9 staining and image processing to develop a rapid loop mediated isothermal amplification (LAMP) detection method for LM. Smartphone was successfully used for detecting the color change in different concentrations of LM. Besides, the optimized LAMP reaction temperature was 63 ℃ by color identification, and the limit of detection for LM was 6 copies/µL in the green channel. So, the developed method, based on image processing, is simple, sensitive and rapid, which provides a new idea and method for rapid detection of LM and other food-borne bacterial pathogens.
Listeriosis is caused by Listeria monocytogenes (LM) and is currently considered to be one of the leading food-borne diseases worldwide, with mortality rate of 20%~30%. Currently, detection methods for LM are time-consuming with low sensitivity, and delayed detection results. SYTO9 has a high affinity for DNA and exhibits enhanced fluorescence upon binding. Therefore, this study used SYTO9 staining and image processing to develop a rapid loop mediated isothermal amplification (LAMP) detection method for LM. Smartphone was successfully used for detecting the color change in different concentrations of LM. Besides, the optimized LAMP reaction temperature was 63 ℃ by color identification, and the limit of detection for LM was 6 copies/µL in the green channel. So, the developed method, based on image processing, is simple, sensitive and rapid, which provides a new idea and method for rapid detection of LM and other food-borne bacterial pathogens.
2022, 33(4): 1936-1940
doi: 10.1016/j.cclet.2021.10.058
Abstract:
Since self-assembled peptide hydrogels can solve the problems such as low solubility, poor selectivity and serious adverse effects of traditional chemotherapy drugs, they have been widely used as carrier materials for drug delivery. In this study, we developed a novel and injectable drug delivery platform for the antitumor drug doxorubicin (DOX) using a pH-responsive ionic-complementary octapeptide FOE. This octapeptide could self-assemble into stable hydrogel under neutral conditions, while disassemble under the tumor microenvironment. Especially, at pH 5.8, its micromorphology displayed a transition from nanofibers to nanospheres with the change of secondary structure, which enhanced cellular uptake of DOX. In addition, FOE hydrogel serves as a smart drug reservoir by localized injection to achieve sustained drug release and improve antitumor efficacy. This octapeptide opens up new avenues for promoting the clinical translation of anticancer drugs on account of excellent injectable properties and economic benefits of simple and short sequence.
Since self-assembled peptide hydrogels can solve the problems such as low solubility, poor selectivity and serious adverse effects of traditional chemotherapy drugs, they have been widely used as carrier materials for drug delivery. In this study, we developed a novel and injectable drug delivery platform for the antitumor drug doxorubicin (DOX) using a pH-responsive ionic-complementary octapeptide FOE. This octapeptide could self-assemble into stable hydrogel under neutral conditions, while disassemble under the tumor microenvironment. Especially, at pH 5.8, its micromorphology displayed a transition from nanofibers to nanospheres with the change of secondary structure, which enhanced cellular uptake of DOX. In addition, FOE hydrogel serves as a smart drug reservoir by localized injection to achieve sustained drug release and improve antitumor efficacy. This octapeptide opens up new avenues for promoting the clinical translation of anticancer drugs on account of excellent injectable properties and economic benefits of simple and short sequence.
2022, 33(4): 1941-1945
doi: 10.1016/j.cclet.2021.10.073
Abstract:
A high incidence of bone defects and the limitation of autologous bone grafting require 3D scaffolds for bone repair. Compared with synthetic materials, natural edible materials possess outstanding advantages in terms of biocompatibility, bioactivities and low manufacturing cost for bone tissue engineering. In this work, attracted by the natural porous/fabric structure, good biocompatibility and bioactivities of the lotus root, the lotus root-based scaffolds were fabricated and investigated their potential to serve as natural porous bone tissue engineering scaffolds. The results indicated that the lotus root-based scaffolds possess suitable natural microstructure, excellent biocompatibility and promising functions, such as antioxidant capacity and angiogenesis promotion. Remarkably, lotus root scaffolds showed encouraging possibility of bone tissue engineering while the mineralized lotus root could further improve the bone regeneration in vivo. All the results demonstrated the bone regeneration potential of lotus root-based scaffolds equipped with suitable natural architecture, excellent biocompatibility, specific bioactivities and low manufacturing cost.
A high incidence of bone defects and the limitation of autologous bone grafting require 3D scaffolds for bone repair. Compared with synthetic materials, natural edible materials possess outstanding advantages in terms of biocompatibility, bioactivities and low manufacturing cost for bone tissue engineering. In this work, attracted by the natural porous/fabric structure, good biocompatibility and bioactivities of the lotus root, the lotus root-based scaffolds were fabricated and investigated their potential to serve as natural porous bone tissue engineering scaffolds. The results indicated that the lotus root-based scaffolds possess suitable natural microstructure, excellent biocompatibility and promising functions, such as antioxidant capacity and angiogenesis promotion. Remarkably, lotus root scaffolds showed encouraging possibility of bone tissue engineering while the mineralized lotus root could further improve the bone regeneration in vivo. All the results demonstrated the bone regeneration potential of lotus root-based scaffolds equipped with suitable natural architecture, excellent biocompatibility, specific bioactivities and low manufacturing cost.
2022, 33(4): 1946-1950
doi: 10.1016/j.cclet.2021.10.071
Abstract:
There is a critical need to diagnose and monitor the progression of Alzheimer's disease (AD) using blood-based biomarkers. At present, it is believed that tau biomarkers can be utilized to reliably detect AD. Multimodal techniques are highly sought after for AD diagnosis and progression monitoring. For this purpose, we developed a fluorescent peptide nanoparticles (f-PNPs) arrays that is capable of detecting multiple signals simultaneously. The concentration, aggregation stages, and Young's modulus of tau biomarkers could be analyzed by monitoring the changes of multimodal fluorescence intensity, nano-morphological, and nano-mechanical properties of the f-PNPs arrays. Experimental results indicated that, compared to healthy human, the concentration, Young's modulus, and aggregation levels of tau proteins in blood samples of clinically diagnosed AD patients increased continuously with the increase of disease severity. The minimally invasive and multimodal characterization techniques showed high signal-to-noise ratio for AD diagnosis.
There is a critical need to diagnose and monitor the progression of Alzheimer's disease (AD) using blood-based biomarkers. At present, it is believed that tau biomarkers can be utilized to reliably detect AD. Multimodal techniques are highly sought after for AD diagnosis and progression monitoring. For this purpose, we developed a fluorescent peptide nanoparticles (f-PNPs) arrays that is capable of detecting multiple signals simultaneously. The concentration, aggregation stages, and Young's modulus of tau biomarkers could be analyzed by monitoring the changes of multimodal fluorescence intensity, nano-morphological, and nano-mechanical properties of the f-PNPs arrays. Experimental results indicated that, compared to healthy human, the concentration, Young's modulus, and aggregation levels of tau proteins in blood samples of clinically diagnosed AD patients increased continuously with the increase of disease severity. The minimally invasive and multimodal characterization techniques showed high signal-to-noise ratio for AD diagnosis.
2022, 33(4): 1951-1955
doi: 10.1016/j.cclet.2021.11.058
Abstract:
Dye desalination is a challenge in the treatment of textile wastewater with high salt concentration. It is imperative to develop salt resistance membrane that is from sustainable materials to effectively treat dye/salt mixtures. And most polymer membrane materials are non-renewable petrochemical resources. In this paper, a green hydrogel membrane (CMCS-OA-NaAlg) was prepared by non-metallic ions of oxalic acid (OA) cross-linking of two natural macromolecules of sodium alginate (NaAlg) and carboxymethyl chitosan (CMCS). The membrane showed excellent anti-swelling at high salt concentration (swelling rate less than 8.0% in 10.0 wt% NaCl solution) and good anti-fouling performance. The membrane exhibited a rejection higher than 95.0% for dyes (bright blue, direct black, direct red, and Congo red) and lower than 7.0% for NaCl, which can achieve better dye/NaCl separation performance. This study provides a promising membrane material for high salt textile wastewater treatment only using water and carbohydrates as raw materials without any organic solvents.
Dye desalination is a challenge in the treatment of textile wastewater with high salt concentration. It is imperative to develop salt resistance membrane that is from sustainable materials to effectively treat dye/salt mixtures. And most polymer membrane materials are non-renewable petrochemical resources. In this paper, a green hydrogel membrane (CMCS-OA-NaAlg) was prepared by non-metallic ions of oxalic acid (OA) cross-linking of two natural macromolecules of sodium alginate (NaAlg) and carboxymethyl chitosan (CMCS). The membrane showed excellent anti-swelling at high salt concentration (swelling rate less than 8.0% in 10.0 wt% NaCl solution) and good anti-fouling performance. The membrane exhibited a rejection higher than 95.0% for dyes (bright blue, direct black, direct red, and Congo red) and lower than 7.0% for NaCl, which can achieve better dye/NaCl separation performance. This study provides a promising membrane material for high salt textile wastewater treatment only using water and carbohydrates as raw materials without any organic solvents.
2022, 33(4): 1956-1962
doi: 10.1016/j.cclet.2021.10.070
Abstract:
A poor biocompatibility and bioactivity of invasive materials remains major problems for biomaterial-based therapy. In this study, we introduced gelatin scaffolds carrying both bone morphogenetic protein-2 (BMP-2) biomimetic peptide and vascular endothelial growth factor-165 (VEGF) that achieved controlled release, cell attachment, proliferation and differentiation. To promote osteogenesis with VEGF, we designed the BMP-2 biomimetic peptide that comprised BMP-2 core sequence oligopeptide (SSVPT), phosphoserine, and synthetic cell adhesion factor (RGDS). In vitro cell experiments, the scaffold was conducive to the adhesion and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs). The micro-CT 3D reconstruction of the rat cranial bone defect model showed that bone regeneration patterns occurred from one side edge towards the center area implanted with the prepared cryogel, and tissue section staining analysis demonstrated that the scaffold with double-growth factor can synergistically accelerate bone regeneration. These findings suggested that the obtained gelatin cryogel could serve as a cell-responsive platform for biomaterial-based nonbearing bone repair.
A poor biocompatibility and bioactivity of invasive materials remains major problems for biomaterial-based therapy. In this study, we introduced gelatin scaffolds carrying both bone morphogenetic protein-2 (BMP-2) biomimetic peptide and vascular endothelial growth factor-165 (VEGF) that achieved controlled release, cell attachment, proliferation and differentiation. To promote osteogenesis with VEGF, we designed the BMP-2 biomimetic peptide that comprised BMP-2 core sequence oligopeptide (SSVPT), phosphoserine, and synthetic cell adhesion factor (RGDS). In vitro cell experiments, the scaffold was conducive to the adhesion and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs). The micro-CT 3D reconstruction of the rat cranial bone defect model showed that bone regeneration patterns occurred from one side edge towards the center area implanted with the prepared cryogel, and tissue section staining analysis demonstrated that the scaffold with double-growth factor can synergistically accelerate bone regeneration. These findings suggested that the obtained gelatin cryogel could serve as a cell-responsive platform for biomaterial-based nonbearing bone repair.
2022, 33(4): 1963-1969
doi: 10.1016/j.cclet.2021.11.047
Abstract:
In clinical settings the wound-dressing was required easy to use and can match the wound area immediately, at the same time they need to have the properties of hemostats, anti-inflammation and promoting wound healing. To get an ideal wound dressing, we developed a type of gel-like wound adhesive patch from spraying double-network hydrogel, which own the properties of self-antibacterial and can promote wound healing. By spraying, the gel-like wound adhesive patch can match the wound area immediately and form a gel-film in 10 s. Sodium carboxymethyl cellulose as pH sensitive materials accelerated the speed to form the gel-film and enhanced ductility of the wound adhesive patch. In vitro experiments show that, this gel-like wound adhesive patch can promote cell proliferation and reduce cell apoptosis. In vivo studies show that, compared with commercialized wound dressings in clinic using, the spraying gel-like wound adhesive patch from our work has a better effect on wound healing. In conclusion, the spraying gel-like wound patch in our work is easy to use and can form a gel-film match on wound area in a short time, also it has the properties of hemostats, anti-inflammation and promoting wound healing. Its feasibility for mass production shows a good potential for commercial use.
In clinical settings the wound-dressing was required easy to use and can match the wound area immediately, at the same time they need to have the properties of hemostats, anti-inflammation and promoting wound healing. To get an ideal wound dressing, we developed a type of gel-like wound adhesive patch from spraying double-network hydrogel, which own the properties of self-antibacterial and can promote wound healing. By spraying, the gel-like wound adhesive patch can match the wound area immediately and form a gel-film in 10 s. Sodium carboxymethyl cellulose as pH sensitive materials accelerated the speed to form the gel-film and enhanced ductility of the wound adhesive patch. In vitro experiments show that, this gel-like wound adhesive patch can promote cell proliferation and reduce cell apoptosis. In vivo studies show that, compared with commercialized wound dressings in clinic using, the spraying gel-like wound adhesive patch from our work has a better effect on wound healing. In conclusion, the spraying gel-like wound patch in our work is easy to use and can form a gel-film match on wound area in a short time, also it has the properties of hemostats, anti-inflammation and promoting wound healing. Its feasibility for mass production shows a good potential for commercial use.
2022, 33(4): 1970-1974
doi: 10.1016/j.cclet.2021.09.090
Abstract:
Polyhaloalkanes are broadly useful yet environmentally harmful stock chemicals, therefore the development of adsorbent materials with capacity and selectivity for polyhaloalkane vapors is highly desirable. Here we report a novel macrocycle WreathArene, a fluorinated C3-symmetrical [16]-paracyclophane. In the crysalline state, WreathArene features guest-adaptive polymorphism for polyhaloalkanes including chloroform, tribromomethane, 1,1,2-trichloroethane, and 1,2-dibromoethane. Non-covalent C-halogen…π interactions are observed in all of these host-guest structures. Based on these properties, the activated WreathArene crystals can be utilized as a selective and recyclable adsorbent for polyhaloalkane vapors with excellent capacity under user-friendly conditions.
Polyhaloalkanes are broadly useful yet environmentally harmful stock chemicals, therefore the development of adsorbent materials with capacity and selectivity for polyhaloalkane vapors is highly desirable. Here we report a novel macrocycle WreathArene, a fluorinated C3-symmetrical [16]-paracyclophane. In the crysalline state, WreathArene features guest-adaptive polymorphism for polyhaloalkanes including chloroform, tribromomethane, 1,1,2-trichloroethane, and 1,2-dibromoethane. Non-covalent C-halogen…π interactions are observed in all of these host-guest structures. Based on these properties, the activated WreathArene crystals can be utilized as a selective and recyclable adsorbent for polyhaloalkane vapors with excellent capacity under user-friendly conditions.
2022, 33(4): 1975-1978
doi: 10.1016/j.cclet.2021.09.070
Abstract:
Novel aggregation-induced charge transfer (CT) emission systems with long luminescence lifetime directed by supramolecular strategy have been successfully developed in water. The dimethylacridine-based electron donor (BrAc) with excellent aggregation ability can co-aggregate with a triazine-based electron acceptor (TRZ) to form nanorods in water, which exhibit CT emission with long lifetime (τ = 0.92 µs). As for a similar electron donor (QaAc) with poor aggregation ability, water-soluble pillar[5]arene (WP5) can be introduced to promote the aggregation process, leading to the obvious CT emission with long lifetime (τ = 0.61 µs). In addition, structural modification of the acceptor with substituent groups possessing stronger electron-accepting capabilities will cause red-shift (about 50 nm) of the emission, which allows conveniently constructing long lifetime organic luminescent materials with different emission colors.
Novel aggregation-induced charge transfer (CT) emission systems with long luminescence lifetime directed by supramolecular strategy have been successfully developed in water. The dimethylacridine-based electron donor (BrAc) with excellent aggregation ability can co-aggregate with a triazine-based electron acceptor (TRZ) to form nanorods in water, which exhibit CT emission with long lifetime (τ = 0.92 µs). As for a similar electron donor (QaAc) with poor aggregation ability, water-soluble pillar[5]arene (WP5) can be introduced to promote the aggregation process, leading to the obvious CT emission with long lifetime (τ = 0.61 µs). In addition, structural modification of the acceptor with substituent groups possessing stronger electron-accepting capabilities will cause red-shift (about 50 nm) of the emission, which allows conveniently constructing long lifetime organic luminescent materials with different emission colors.
2022, 33(4): 1979-1982
doi: 10.1016/j.cclet.2021.10.040
Abstract:
Dansylamide (DNSA) is a typical ICT probe that has a favorable serum albumin sensitivity. Inspired by this, we designed a microenvironment sensitive fluorescent probe 4C-G through introducing DNSA into pillar[5]arene. Unlike DNSA, 4C-G displayed differentiated sensitivity to multiple proteins, which was benefit from pillar[5]arene assisted the probe to form complexes with proteins. 4C-G could not only be applied in imaging of HepG2, but also act as a favorable drug carrier for regorafenib (REG) encapsulation. The 4C-G-REG complex would aggregate into high drug-loading fluorescent nanoparticles in a physiological environment (pH 7.4). Such nanoparticles exhibited pH-triggered enrichment ability, which rapidly enriched REG in the acidic environment (pH 6.0). Furthermore, the complexation between 4C-G and REG maintained the imaging property of the probe and the excellent anticancer activity of the drug on HepG2.
Dansylamide (DNSA) is a typical ICT probe that has a favorable serum albumin sensitivity. Inspired by this, we designed a microenvironment sensitive fluorescent probe 4C-G through introducing DNSA into pillar[5]arene. Unlike DNSA, 4C-G displayed differentiated sensitivity to multiple proteins, which was benefit from pillar[5]arene assisted the probe to form complexes with proteins. 4C-G could not only be applied in imaging of HepG2, but also act as a favorable drug carrier for regorafenib (REG) encapsulation. The 4C-G-REG complex would aggregate into high drug-loading fluorescent nanoparticles in a physiological environment (pH 7.4). Such nanoparticles exhibited pH-triggered enrichment ability, which rapidly enriched REG in the acidic environment (pH 6.0). Furthermore, the complexation between 4C-G and REG maintained the imaging property of the probe and the excellent anticancer activity of the drug on HepG2.
2022, 33(4): 1983-1987
doi: 10.1016/j.cclet.2021.09.095
Abstract:
Pillararenes are a new type of supramolecular hosts, and they have been widely applied in drug delivery, catalysis, separation process, and sensors. However, they have rarely been used to produce hydrogen. Here, we report that pillararenes were used as functional molecules to explore photocatalysts and efficiently promoted hydrogen production from water. The most common and easily synthesized p-dimethoxy pillar[5]arene (PI-OMe) was employed to form an organic-inorganic hybrid material with titanium dioxide (TiO2), denoted as PI-OMe-TiO2, using a convenient sol-gel method. When the material was loaded with Pt nanoparticles, the resulting Pt/PI-OMe-TiO2 had a good activity and stability in catalyzing water splitting to produce hydrogen under visible light. The optimized catalyst Pt/PI-OMe-TiO2(5.2 wt%) had a photocatalytic hydrogen production rate of 1736 µmol g−1 h−1 under visible light (λ > 420 nm) irradiation. The catalyst with a Pt loading of 0.5 wt% and a PI-OMe content of 5.2 wt% also showed good long-term durability after 10 cycles of 50 h testing. The total amount of hydrogen produced was 65.01 mmol/g, and the corresponding turnover number (TON) value was 2084. Our findings suggest that pillararene derivatives are promising functional molecules to make efficient and stable hybrid photocatalysts with TiO2 and open a new door to hydrogen production using visible light.
Pillararenes are a new type of supramolecular hosts, and they have been widely applied in drug delivery, catalysis, separation process, and sensors. However, they have rarely been used to produce hydrogen. Here, we report that pillararenes were used as functional molecules to explore photocatalysts and efficiently promoted hydrogen production from water. The most common and easily synthesized p-dimethoxy pillar[5]arene (PI-OMe) was employed to form an organic-inorganic hybrid material with titanium dioxide (TiO2), denoted as PI-OMe-TiO2, using a convenient sol-gel method. When the material was loaded with Pt nanoparticles, the resulting Pt/PI-OMe-TiO2 had a good activity and stability in catalyzing water splitting to produce hydrogen under visible light. The optimized catalyst Pt/PI-OMe-TiO2(5.2 wt%) had a photocatalytic hydrogen production rate of 1736 µmol g−1 h−1 under visible light (λ > 420 nm) irradiation. The catalyst with a Pt loading of 0.5 wt% and a PI-OMe content of 5.2 wt% also showed good long-term durability after 10 cycles of 50 h testing. The total amount of hydrogen produced was 65.01 mmol/g, and the corresponding turnover number (TON) value was 2084. Our findings suggest that pillararene derivatives are promising functional molecules to make efficient and stable hybrid photocatalysts with TiO2 and open a new door to hydrogen production using visible light.
2022, 33(4): 1988-1992
doi: 10.1016/j.cclet.2021.10.017
Abstract:
A three-dimensional flexible organic framework FOF-1 has been synthesized from the condensation of a tetratopic acylhydrazine and a rigid 4,4′-diphenyl-4,4′-bipyridinium dialdehyde in water through the quantitative formation of hydrazone bond. FOF-1 is further applied to construct a polycatenane framework FOF-pc-1 through the quantitative cucurbit[7]uril encapsulation for the diphenylbipyridinium subunits of the framework by making use of the dynamic nature of the hydrazone bond in water. The bipyridinium subunits in both frameworks can be reduced their radical cation counterparts to produce conjugated radical cation-linked dynamic organic frameworks rc-FOF-1 or rc-FOF-pc-1. Polycatenation is revealed to enhance the stability of the dynamic frameworks in water, whereas depolycatenation can be reached for both FOF-pc-1 and rc-FOF-pc-1 by using a ferrocene guest to form a more stable complex with CB[7].
A three-dimensional flexible organic framework FOF-1 has been synthesized from the condensation of a tetratopic acylhydrazine and a rigid 4,4′-diphenyl-4,4′-bipyridinium dialdehyde in water through the quantitative formation of hydrazone bond. FOF-1 is further applied to construct a polycatenane framework FOF-pc-1 through the quantitative cucurbit[7]uril encapsulation for the diphenylbipyridinium subunits of the framework by making use of the dynamic nature of the hydrazone bond in water. The bipyridinium subunits in both frameworks can be reduced their radical cation counterparts to produce conjugated radical cation-linked dynamic organic frameworks rc-FOF-1 or rc-FOF-pc-1. Polycatenation is revealed to enhance the stability of the dynamic frameworks in water, whereas depolycatenation can be reached for both FOF-pc-1 and rc-FOF-pc-1 by using a ferrocene guest to form a more stable complex with CB[7].
2022, 33(4): 1993-1996
doi: 10.1016/j.cclet.2021.10.018
Abstract:
Solvent-free luminescent molecular liquids (LMLs), which exhibit nonvolatile fluidic nature and active optoelectronic properties, were widely used. For further development, we introduced siloxane units into AIE molecules, designed and synthesized TPE derivatives with siloxane side chains via facile Piers-Rubinsztajn reaction. The obtained AIE molecular liquids exhibit unique photophysical properties. Compared with the obtained alkyl TPE-solids, siloxane TPE show liquid state, which proves that the siloxane units have stronger liquefaction effect than alkyl. Viscosity test shows that siloxane TPE-liquids has far more lower viscosity and better fluidity than the long-chain alkyl molecular liquids in previous research. All those properties are attributed to the weak interaction between flexible molecular chains of siloxane. Besides, fluorescence test shows temperature responsiveness of siloxane TPE-liquids. We developed this low-viscosity nonvolatile AIE molecular liquid as green fluorescent ink.
Solvent-free luminescent molecular liquids (LMLs), which exhibit nonvolatile fluidic nature and active optoelectronic properties, were widely used. For further development, we introduced siloxane units into AIE molecules, designed and synthesized TPE derivatives with siloxane side chains via facile Piers-Rubinsztajn reaction. The obtained AIE molecular liquids exhibit unique photophysical properties. Compared with the obtained alkyl TPE-solids, siloxane TPE show liquid state, which proves that the siloxane units have stronger liquefaction effect than alkyl. Viscosity test shows that siloxane TPE-liquids has far more lower viscosity and better fluidity than the long-chain alkyl molecular liquids in previous research. All those properties are attributed to the weak interaction between flexible molecular chains of siloxane. Besides, fluorescence test shows temperature responsiveness of siloxane TPE-liquids. We developed this low-viscosity nonvolatile AIE molecular liquid as green fluorescent ink.
2022, 33(4): 1997-2000
doi: 10.1016/j.cclet.2021.09.067
Abstract:
An efficient photocatalytic alkylation/cyclization of allylic amide with N-hydroxyphthalimide ester has been developed. The transformation is taken advantage of alkyl radicals to attack allylic amide with the assist of inexpensive rose bengal as photocatalyst to prepare a series of alkyl substituted oxazolines in moderate to excellent yields. High regioselectivity, operational safety, mild conditions and excellent substrate generality give this protocol broad application prospects.
An efficient photocatalytic alkylation/cyclization of allylic amide with N-hydroxyphthalimide ester has been developed. The transformation is taken advantage of alkyl radicals to attack allylic amide with the assist of inexpensive rose bengal as photocatalyst to prepare a series of alkyl substituted oxazolines in moderate to excellent yields. High regioselectivity, operational safety, mild conditions and excellent substrate generality give this protocol broad application prospects.
2022, 33(4): 2001-2004
doi: 10.1016/j.cclet.2021.09.071
Abstract:
The modification and functionalization of peptides is of great significance in modern biotechnology and drug development. Here we report a highly reactive Michael-type warhead for the covalently modification of cysteine on peptide and protein. By installing a vinyl group onto a methionine residue of peptide, the produced vinyl sulfonium can be efficiently nucleophilic added by appropriate cysteine residue of this peptide, and thus yield a cyclized peptide. This peptide cyclization strategy was proven to exhibit improved cell penetration and good stability. Moreover, a peptide ligand bearing vinyl sulfonium could covalently bind to the cysteine in the target protein, indicating the potential of vinyl sulfonium as a novel warhead for developing covalent peptide inhibitor.
The modification and functionalization of peptides is of great significance in modern biotechnology and drug development. Here we report a highly reactive Michael-type warhead for the covalently modification of cysteine on peptide and protein. By installing a vinyl group onto a methionine residue of peptide, the produced vinyl sulfonium can be efficiently nucleophilic added by appropriate cysteine residue of this peptide, and thus yield a cyclized peptide. This peptide cyclization strategy was proven to exhibit improved cell penetration and good stability. Moreover, a peptide ligand bearing vinyl sulfonium could covalently bind to the cysteine in the target protein, indicating the potential of vinyl sulfonium as a novel warhead for developing covalent peptide inhibitor.
2022, 33(4): 2005-2008
doi: 10.1016/j.cclet.2021.09.081
Abstract:
A novel method for metal-free C-H borylation of 2-(N-methylanilino)-5-fluoropyridines and 2-benzyl-5-fluoropyridines has been reported. The 5-fluoropyridine directed borylation reaction exhibited high efficiency and site exclusivity. The useful protocol could be executed on a gram-scale easily and the borylated products showed good derivatization applications. Moreover, the practicality of the strategy was expanded by the fact that the directing group could be removed in an acceptable yield.
A novel method for metal-free C-H borylation of 2-(N-methylanilino)-5-fluoropyridines and 2-benzyl-5-fluoropyridines has been reported. The 5-fluoropyridine directed borylation reaction exhibited high efficiency and site exclusivity. The useful protocol could be executed on a gram-scale easily and the borylated products showed good derivatization applications. Moreover, the practicality of the strategy was expanded by the fact that the directing group could be removed in an acceptable yield.
2022, 33(4): 2009-2014
doi: 10.1016/j.cclet.2021.10.016
Abstract:
Both sulfur and fluorine play important roles in organic synthesis, the life science, and materials science. The direct incorporation of these elements into organic scaffolds with precise control of the oxidation states of sulfur moieties is of great significance. Herein, we report the highly selective electrochemical vicinal fluorosulfenylation and fluorosulfoxidation reactions of alkenes, which were enabled by the unique ability of electrochemistry to dial in the potentials on demand. Preliminary mechanistic investigations revealed that the fluorosulfenylation reaction proceeded through a radical-polar crossover mechanism involving a key episulfonium ion intermediate. Subsequent electrochemical oxidation of fluorosulfides to fluorosulfoxides were readily achieved under a higher applied potential with the adventitious H2O in the reaction mixture.
Both sulfur and fluorine play important roles in organic synthesis, the life science, and materials science. The direct incorporation of these elements into organic scaffolds with precise control of the oxidation states of sulfur moieties is of great significance. Herein, we report the highly selective electrochemical vicinal fluorosulfenylation and fluorosulfoxidation reactions of alkenes, which were enabled by the unique ability of electrochemistry to dial in the potentials on demand. Preliminary mechanistic investigations revealed that the fluorosulfenylation reaction proceeded through a radical-polar crossover mechanism involving a key episulfonium ion intermediate. Subsequent electrochemical oxidation of fluorosulfides to fluorosulfoxides were readily achieved under a higher applied potential with the adventitious H2O in the reaction mixture.
2022, 33(4): 2015-2020
doi: 10.1016/j.cclet.2021.10.043
Abstract:
The development of innovative strategies and methods to provide natural product-like macrocycles not accessible by biosynthesis, but endowed with novel bioactivities and simplified structure, is highly desirable. Inspired by the key scaffolds of rapamycin and FR252921, herein, we report a Rh(Ⅲ)-catalyzed C-H alkylation macrocyclization, which enables access to CF3-substituted macrolides. DFT calculations reveal that the chemoselectivity between C-H alkylation and olefination macrocyclization was highly controllable. Moreover, the unique CF3-substituted macrolides showed potent anti-inflammation activities against TNF-α, IL-6 and CCL2 mRNA expression.
The development of innovative strategies and methods to provide natural product-like macrocycles not accessible by biosynthesis, but endowed with novel bioactivities and simplified structure, is highly desirable. Inspired by the key scaffolds of rapamycin and FR252921, herein, we report a Rh(Ⅲ)-catalyzed C-H alkylation macrocyclization, which enables access to CF3-substituted macrolides. DFT calculations reveal that the chemoselectivity between C-H alkylation and olefination macrocyclization was highly controllable. Moreover, the unique CF3-substituted macrolides showed potent anti-inflammation activities against TNF-α, IL-6 and CCL2 mRNA expression.
2022, 33(4): 2021-2025
doi: 10.1016/j.cclet.2021.09.104
Abstract:
Noble metal aerogels (NMAs), belonging to the porous material, have exhibited excellent catalytic performance. Although the synthesis method continues to improve, it still exists some problems which hindered the experimental process, such as high concentration of noble metal precursors, long synthesis cycle, expensive production cost, and uncontrollable ligament length. In this work, ultrasonic wave and reducing agent NaBH4 were simultaneously applied to gelation process. With the cavitation of ultrasound, it can generate huge energy with heating and stirring, thus gelation reaction proceeded quickly, and even completed the process in only a few seconds, that is much faster than the recorded. A wide concentration range was successfully expanded from 0.02 mmol/L to 62.5 mmol/L. Further, we extended this method to a variety of noble metal elements (Au, Ru, Rh, Ag, Pt, Pd), and this method is adaptive for the synthesis of single metal aerogels (Au, Ag, Ru, Rh, Pd), bimetal and trimetal aerogels (Au-Ag, Au-Rh, Au-Ru, Au-Pt, Au-Pd, Au-Pt-Pd). In addition, the ligament size of alloy aerogels are 10 nm or less. Moreover, their brilliant properties were demonstrated in hydrogen evolution reaction (HER) and ethanol oxidation reaction (EOR).
Noble metal aerogels (NMAs), belonging to the porous material, have exhibited excellent catalytic performance. Although the synthesis method continues to improve, it still exists some problems which hindered the experimental process, such as high concentration of noble metal precursors, long synthesis cycle, expensive production cost, and uncontrollable ligament length. In this work, ultrasonic wave and reducing agent NaBH4 were simultaneously applied to gelation process. With the cavitation of ultrasound, it can generate huge energy with heating and stirring, thus gelation reaction proceeded quickly, and even completed the process in only a few seconds, that is much faster than the recorded. A wide concentration range was successfully expanded from 0.02 mmol/L to 62.5 mmol/L. Further, we extended this method to a variety of noble metal elements (Au, Ru, Rh, Ag, Pt, Pd), and this method is adaptive for the synthesis of single metal aerogels (Au, Ag, Ru, Rh, Pd), bimetal and trimetal aerogels (Au-Ag, Au-Rh, Au-Ru, Au-Pt, Au-Pd, Au-Pt-Pd). In addition, the ligament size of alloy aerogels are 10 nm or less. Moreover, their brilliant properties were demonstrated in hydrogen evolution reaction (HER) and ethanol oxidation reaction (EOR).
2022, 33(4): 2026-2030
doi: 10.1016/j.cclet.2021.09.089
Abstract:
Artificial membrane transporters that either use chalcogen bonds to facilitate transmembrane flux of anions or show high selectivity toward perchlorate anions are rare. In this work, we report on one such novel monopeptide-based transporter system, featuring both chalcogen bonds for highly efficient anion transport and high transport selectivity toward ClO4- anions. Structurally, these monopeptide molecules associate with each other via H-bonds to produce H-bonded 1D stack that not only one dimensionally but also directionally aligns the terminal bicyclic thiophene motifs to the same side. Functionally, these well-aligned thiophenes create a sulfur-rich transmembrane pathway, combinatorially fine-tunable to enable anions to efficiently cross the membrane in the increasing activity of Cl- < Br- < NO3- < ClO4- via chalcogen bonds, with EC50 values of 0.75, 0.40, 0.37 and 0.093 μmol/L (0.3 mol% relative to lipid molecules), respectively.
Artificial membrane transporters that either use chalcogen bonds to facilitate transmembrane flux of anions or show high selectivity toward perchlorate anions are rare. In this work, we report on one such novel monopeptide-based transporter system, featuring both chalcogen bonds for highly efficient anion transport and high transport selectivity toward ClO4- anions. Structurally, these monopeptide molecules associate with each other via H-bonds to produce H-bonded 1D stack that not only one dimensionally but also directionally aligns the terminal bicyclic thiophene motifs to the same side. Functionally, these well-aligned thiophenes create a sulfur-rich transmembrane pathway, combinatorially fine-tunable to enable anions to efficiently cross the membrane in the increasing activity of Cl- < Br- < NO3- < ClO4- via chalcogen bonds, with EC50 values of 0.75, 0.40, 0.37 and 0.093 μmol/L (0.3 mol% relative to lipid molecules), respectively.
2022, 33(4): 2031-2035
doi: 10.1016/j.cclet.2021.10.010
Abstract:
The Cu(I)-catalyzed [4 + 1] annulation of vinyl indoles and a carbene precursor is a powerful method for constructing cyclopentaindole derivatives. Density functional theory (DFT) calculations were used to elucidate the mechanism and regioselectivity of this reaction. After Cu-assisted indole C3-alkylation, direct 1,5-annulation was favored over the Cu-assisted annulation pathway. Furthermore, the regioselectivity for 1,5-annulation was attributed to the generated five-membered-ring product being more stable than the three-membered-ring product from 1,3-annulation, which was the kinetically favored pathway.
The Cu(I)-catalyzed [4 + 1] annulation of vinyl indoles and a carbene precursor is a powerful method for constructing cyclopentaindole derivatives. Density functional theory (DFT) calculations were used to elucidate the mechanism and regioselectivity of this reaction. After Cu-assisted indole C3-alkylation, direct 1,5-annulation was favored over the Cu-assisted annulation pathway. Furthermore, the regioselectivity for 1,5-annulation was attributed to the generated five-membered-ring product being more stable than the three-membered-ring product from 1,3-annulation, which was the kinetically favored pathway.
2022, 33(4): 2036-2040
doi: 10.1016/j.cclet.2021.09.069
Abstract:
Herein, an efficient molecular oxygen-mediated method for the selective hydroxyalkylation and alkylation of quinoxalin-2(1H)-ones with alkylboronic acids under transition-metal free conditions has been developed. This strategy demonstrates a broad scope of quinoxalin-2(1H)-ones and alkylboronic acids, giving 3-hydroxyalkylquinoxalin-2(1H)-ones and 3-alkylquinoxalin-2(1H)-ones in moderate-to-good yield. Control experiments reveal that a radical pathway is involved.
Herein, an efficient molecular oxygen-mediated method for the selective hydroxyalkylation and alkylation of quinoxalin-2(1H)-ones with alkylboronic acids under transition-metal free conditions has been developed. This strategy demonstrates a broad scope of quinoxalin-2(1H)-ones and alkylboronic acids, giving 3-hydroxyalkylquinoxalin-2(1H)-ones and 3-alkylquinoxalin-2(1H)-ones in moderate-to-good yield. Control experiments reveal that a radical pathway is involved.
2022, 33(4): 2041-2043
doi: 10.1016/j.cclet.2021.09.030
Abstract:
Dimeric sesquiterpenoids possessing densely substituted 7-norbornenone/7-norbornenol motifs pose a considerable challenge for chemical synthesis. From a strategic perspective, one could envision intermolecular Diels−Alder cycloaddition as a straightforward method for assembling alkyl-substituted 7-norbornenones. However, this approach is hindered by lability of the required dienes, namely alkyl-substituted cyclopentadienones. Here we report a one-pot protocol for construction of alkyl-substituted 7-norbornenones from electron-deficient olefins and a cyclopentenone derivative. DDQ was found to be an effective oxidant for generating a cyclopentadienone intermediate in situ from the enone. A series of sterically congested 7-norbornenone-containing polycyclic compounds were prepared by using this protocol.
Dimeric sesquiterpenoids possessing densely substituted 7-norbornenone/7-norbornenol motifs pose a considerable challenge for chemical synthesis. From a strategic perspective, one could envision intermolecular Diels−Alder cycloaddition as a straightforward method for assembling alkyl-substituted 7-norbornenones. However, this approach is hindered by lability of the required dienes, namely alkyl-substituted cyclopentadienones. Here we report a one-pot protocol for construction of alkyl-substituted 7-norbornenones from electron-deficient olefins and a cyclopentenone derivative. DDQ was found to be an effective oxidant for generating a cyclopentadienone intermediate in situ from the enone. A series of sterically congested 7-norbornenone-containing polycyclic compounds were prepared by using this protocol.
2022, 33(4): 2044-2046
doi: 10.1016/j.cclet.2021.09.032
Abstract:
A catalytic asymmetric total synthesis of (+)-vincamine is presented. Key features of the synthesis include a Pd-catalyzed enantioselective decarboxylative allylation to form the C20 quaternary stereogenic center and a stereoselective iminium reduction to install the critical cis-C20/C21 relative stereochemisty.
A catalytic asymmetric total synthesis of (+)-vincamine is presented. Key features of the synthesis include a Pd-catalyzed enantioselective decarboxylative allylation to form the C20 quaternary stereogenic center and a stereoselective iminium reduction to install the critical cis-C20/C21 relative stereochemisty.
Facile one-pot synthesis of a novel all-carbon stair containing dimerized pentalene core from alkyne
2022, 33(4): 2047-2051
doi: 10.1016/j.cclet.2021.10.036
Abstract:
The construction of all-carbon molecule frameworks remains challenging. Herein, we report a facile and efficient one-pot synthesis of a novel all-carbon stair containing dimerized pentalene core using inexpensive cyclopropyl alkyne catalyzed by in situ generated Cu(I) from the comproportionation reaction of Cu(II) salt and Cu powder under mild reaction conditions. The reaction proceeds via sequential acetylenic coupling, followed by cyclization and [2 + 2] cycloaddition to directly produce pentalene dimer, which is difficult to access by other established methods. Different mechanistic paths were studied for the pentalene formation using density functional theory, suggesting that the reaction also proceeds through acetylenic coupling followed by cyclization and [2 + 2] cycloaddition. Based on the activation energy barriers, Path 1 has the rate-determining step of 38.63 kcal/mol, which is the most thermodynamically preferred one among the four paths.
The construction of all-carbon molecule frameworks remains challenging. Herein, we report a facile and efficient one-pot synthesis of a novel all-carbon stair containing dimerized pentalene core using inexpensive cyclopropyl alkyne catalyzed by in situ generated Cu(I) from the comproportionation reaction of Cu(II) salt and Cu powder under mild reaction conditions. The reaction proceeds via sequential acetylenic coupling, followed by cyclization and [2 + 2] cycloaddition to directly produce pentalene dimer, which is difficult to access by other established methods. Different mechanistic paths were studied for the pentalene formation using density functional theory, suggesting that the reaction also proceeds through acetylenic coupling followed by cyclization and [2 + 2] cycloaddition. Based on the activation energy barriers, Path 1 has the rate-determining step of 38.63 kcal/mol, which is the most thermodynamically preferred one among the four paths.
2022, 33(4): 2052-2056
doi: 10.1016/j.cclet.2021.09.055
Abstract:
Point mutations can be used as biomarkers to perform diagnosis for diseases. In this study, a nanorobot for low-abundance point mutation enrichment was constructed using DNA origami. The novel design achieved limits of detection of 0.1% and 1% for synthesized DNA samples and clinical gene samples, respectively. Resettability was a key property of this method, which also involved a simpler process, lower cost and shorter detection duration than traditional enrichment methods. This novel DNA nanorobot may enable the detection of tumor markers, potentially facilitating early cancer diagnosis.
Point mutations can be used as biomarkers to perform diagnosis for diseases. In this study, a nanorobot for low-abundance point mutation enrichment was constructed using DNA origami. The novel design achieved limits of detection of 0.1% and 1% for synthesized DNA samples and clinical gene samples, respectively. Resettability was a key property of this method, which also involved a simpler process, lower cost and shorter detection duration than traditional enrichment methods. This novel DNA nanorobot may enable the detection of tumor markers, potentially facilitating early cancer diagnosis.
2022, 33(4): 2057-2059
doi: 10.1016/j.cclet.2021.09.073
Abstract:
A novel meroterpenoid, named meroterpenthiazole A (1), was isolated from the deep-sea-derived Penicillium allii-sativi. Its structure was established by extensive spectroscopic and computational methods. Meroterpenthiazole A bears a rare benzothiazole moiety in nature. Compound 1 significantly inhibited retinoid X receptor (RXR)-α transcriptional effect (KD = 12.3 µmol/L) through a novel binding mechanism.
A novel meroterpenoid, named meroterpenthiazole A (1), was isolated from the deep-sea-derived Penicillium allii-sativi. Its structure was established by extensive spectroscopic and computational methods. Meroterpenthiazole A bears a rare benzothiazole moiety in nature. Compound 1 significantly inhibited retinoid X receptor (RXR)-α transcriptional effect (KD = 12.3 µmol/L) through a novel binding mechanism.
2022, 33(4): 2060-2064
doi: 10.1016/j.cclet.2021.08.082
Abstract:
Due to the involvement of four-electron transfer process at photoanode, water oxidation is the rate-limiting step in water splitting reaction. To settle this dilemma, ZnCo2O4 nanoparticles are combined with BiVO4 to form a p-n ZnCo2O4/BiVO4 heterojunction photoanode, which is proved by an input voltage−output current test. The built-in electric field formed within the heterojunction structure promotes the effective separation of electrons and holes. ZnCo2O4 is also an effective water oxidation cocatalyst, since it could cause the holes entering the electrode/electrolyte interface rapidly for the subsequent water oxidation reaction. The photocurrent density of ZnCo2O4/BiVO4 composite photoanode reaches 3.0 mA/cm2 at 1.23 V vs. RHE in 0.5 mol/L sodium sulfate under AM 1.5G simulated sunlight, about 2.1 times greater than that of BiVO4 (1.4 mA/cm2). These results suggest the potential of ZnCo2O4 nanoparticles for improving photoelectrochemical water splitting anode materials.
Due to the involvement of four-electron transfer process at photoanode, water oxidation is the rate-limiting step in water splitting reaction. To settle this dilemma, ZnCo2O4 nanoparticles are combined with BiVO4 to form a p-n ZnCo2O4/BiVO4 heterojunction photoanode, which is proved by an input voltage−output current test. The built-in electric field formed within the heterojunction structure promotes the effective separation of electrons and holes. ZnCo2O4 is also an effective water oxidation cocatalyst, since it could cause the holes entering the electrode/electrolyte interface rapidly for the subsequent water oxidation reaction. The photocurrent density of ZnCo2O4/BiVO4 composite photoanode reaches 3.0 mA/cm2 at 1.23 V vs. RHE in 0.5 mol/L sodium sulfate under AM 1.5G simulated sunlight, about 2.1 times greater than that of BiVO4 (1.4 mA/cm2). These results suggest the potential of ZnCo2O4 nanoparticles for improving photoelectrochemical water splitting anode materials.
2022, 33(4): 2065-2068
doi: 10.1016/j.cclet.2021.09.035
Abstract:
Metal-organic frameworks (MOFs) as a type of crystalline heterogeneous catalysts have shown potential application in photocatalytic CO2 reduction. However, MOF catalysts with high efficiency and selectivity are still in pursuit. Herein, by a bimetallic strategy, the catalytic performance of a Co-MOF for photocatalytic CO2 reduction was enhanced. Specifically, the Co-MOF based on 4, 5-dicarboxylic acid (H3IDC) and 4, 4ʹ-bipydine (4, 4ʹ-bpy) can catalyze CO2 reduction to CO, with high efficiency but relatively low selectivity. After replacement of 2/3 Co(Ⅱ) with Ni(Ⅱ) within Co-MOF, the resulted isostructural Co1Ni2-MOF not only retains high efficiency for photocatalytic CO2 reduction, but also shows enhanced CO selectivity. The CO evolution rate reaches 1160 µmol g−1 h−1 and the CO selectivity reaches as high as 94.6%. The enhanced photocatalytic CO2 reduction performance is supported by theoretical calculation results. This case demonstrates that bimetallic strategy is an effective mean to optimize the catalytic performance of MOF catalysts for photochemical CO2 reduction.
Metal-organic frameworks (MOFs) as a type of crystalline heterogeneous catalysts have shown potential application in photocatalytic CO2 reduction. However, MOF catalysts with high efficiency and selectivity are still in pursuit. Herein, by a bimetallic strategy, the catalytic performance of a Co-MOF for photocatalytic CO2 reduction was enhanced. Specifically, the Co-MOF based on 4, 5-dicarboxylic acid (H3IDC) and 4, 4ʹ-bipydine (4, 4ʹ-bpy) can catalyze CO2 reduction to CO, with high efficiency but relatively low selectivity. After replacement of 2/3 Co(Ⅱ) with Ni(Ⅱ) within Co-MOF, the resulted isostructural Co1Ni2-MOF not only retains high efficiency for photocatalytic CO2 reduction, but also shows enhanced CO selectivity. The CO evolution rate reaches 1160 µmol g−1 h−1 and the CO selectivity reaches as high as 94.6%. The enhanced photocatalytic CO2 reduction performance is supported by theoretical calculation results. This case demonstrates that bimetallic strategy is an effective mean to optimize the catalytic performance of MOF catalysts for photochemical CO2 reduction.
2022, 33(4): 2069-2072
doi: 10.1016/j.cclet.2021.08.120
Abstract:
Supported NiCu bimetallic catalysts have been produced in-situ on commercial Al2O3 by using layered double hydroxides as precursors. The resulting catalysts show a uniform Ni and Cu distribution, thus providing good activity and selectivity in the reforming reaction of n-heptane. The catalytic performance has been found to depend on the Cu/Ni ratio, revealing the synergic catalysis between homogeneously dispersed Ni and Cu sites. The good catalysis of NiCu bimetallic catalysts makes it possible to partly or even completely replace Pt with NiCu bimetallic catalysts.
Supported NiCu bimetallic catalysts have been produced in-situ on commercial Al2O3 by using layered double hydroxides as precursors. The resulting catalysts show a uniform Ni and Cu distribution, thus providing good activity and selectivity in the reforming reaction of n-heptane. The catalytic performance has been found to depend on the Cu/Ni ratio, revealing the synergic catalysis between homogeneously dispersed Ni and Cu sites. The good catalysis of NiCu bimetallic catalysts makes it possible to partly or even completely replace Pt with NiCu bimetallic catalysts.
2022, 33(4): 2073-2076
doi: 10.1016/j.cclet.2021.08.034
Abstract:
Application of matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to investigate the spatiotemporal alterations of lipids in biological tissues has brought many significant results. However, the presence of structural isomers varying in C=C double bond (DB) locations makes isomer-resolved MSI an urgent need. Herein, we introduce a new type of light-driven on-tissue [2 + 2] cycloaddition reaction coupled with MALDI-MS/MS imaging to identify lipid DB position isomers and their spatial signatures in biological tissues. 3-Benzoylpyridine was introduced as a novel derivatization reagent, and it exhibited great reactivity toward lipid C=C bond to form oxetanes under both ultraviolet light and visible light irradiation. With this approach, DB position isomers of lipids were imaged with highly differential levels in distinct regions of rat brain, providing an accurate and spatially resolved approach to study tissue lipidomics.
Application of matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to investigate the spatiotemporal alterations of lipids in biological tissues has brought many significant results. However, the presence of structural isomers varying in C=C double bond (DB) locations makes isomer-resolved MSI an urgent need. Herein, we introduce a new type of light-driven on-tissue [2 + 2] cycloaddition reaction coupled with MALDI-MS/MS imaging to identify lipid DB position isomers and their spatial signatures in biological tissues. 3-Benzoylpyridine was introduced as a novel derivatization reagent, and it exhibited great reactivity toward lipid C=C bond to form oxetanes under both ultraviolet light and visible light irradiation. With this approach, DB position isomers of lipids were imaged with highly differential levels in distinct regions of rat brain, providing an accurate and spatially resolved approach to study tissue lipidomics.
2022, 33(4): 2077-2080
doi: 10.1016/j.cclet.2021.08.066
Abstract:
N6-methyldeoxyadenosine (6mdA) modification is considered as a new epigenetic mark that may play important roles in various biological processes. However, it remains unclear about the effect of 6mdA on DNA replication in human cells. Herein, we combined next-generation sequencing with shuttle vector technology to explore how 6mdA affects the efficiency and accuracy of DNA replication in human cells. Our results showed that 6mdA neither blocked DNA replication nor induced mutations in human cells. Moreover, we found that the depletion of translesion synthesis DNA polymerase (Pol) κ, Pol η, Pol ι or Pol ζ did not significantly change the biological consequences of 6mdA during replication in human cells. The negligible impact of 6mdA on DNA replication is consistent with its potential role in epigenetic gene expression.
N6-methyldeoxyadenosine (6mdA) modification is considered as a new epigenetic mark that may play important roles in various biological processes. However, it remains unclear about the effect of 6mdA on DNA replication in human cells. Herein, we combined next-generation sequencing with shuttle vector technology to explore how 6mdA affects the efficiency and accuracy of DNA replication in human cells. Our results showed that 6mdA neither blocked DNA replication nor induced mutations in human cells. Moreover, we found that the depletion of translesion synthesis DNA polymerase (Pol) κ, Pol η, Pol ι or Pol ζ did not significantly change the biological consequences of 6mdA during replication in human cells. The negligible impact of 6mdA on DNA replication is consistent with its potential role in epigenetic gene expression.
2022, 33(4): 2081-2085
doi: 10.1016/j.cclet.2021.08.083
Abstract:
Although peroxidase-like nanozymes have made great progress in bioanalysis, few current nanozyme-based biosensors are constructed for discriminating isomers of organic compounds. Herein, fluorescent metal-organic framework (MOF)-based nanozyme is utilized for phenylenediamine isomers discrimination and detection. NH2-MIL-101(Fe), as a member of Fe-based MOFs, functions as not only fluorescent indicator but also peroxidase mimics. In the presence of H2O2, NH2-MIL-101(Fe) can catalyze the oxidation of o-phenylenediamine (OPD) and p-phenylenediamine (PPD) into their corresponding oxidation products (OPDox and PPDox), which in turn quench its intrinsic fluorescence at 445 nm via inner filter effect (IFE). Differently, a new fluorescence peak at 574 nm is observed for OPDox. Thus, a ratiometric fluorescence method for the detection of OPD can be designed with the fluorescence intensity ratio F574/F445 as readout. This proposed strategy displays excellent discrimination ability for three phenylenediamines and may open new applications of MOFs in environmental science.
Although peroxidase-like nanozymes have made great progress in bioanalysis, few current nanozyme-based biosensors are constructed for discriminating isomers of organic compounds. Herein, fluorescent metal-organic framework (MOF)-based nanozyme is utilized for phenylenediamine isomers discrimination and detection. NH2-MIL-101(Fe), as a member of Fe-based MOFs, functions as not only fluorescent indicator but also peroxidase mimics. In the presence of H2O2, NH2-MIL-101(Fe) can catalyze the oxidation of o-phenylenediamine (OPD) and p-phenylenediamine (PPD) into their corresponding oxidation products (OPDox and PPDox), which in turn quench its intrinsic fluorescence at 445 nm via inner filter effect (IFE). Differently, a new fluorescence peak at 574 nm is observed for OPDox. Thus, a ratiometric fluorescence method for the detection of OPD can be designed with the fluorescence intensity ratio F574/F445 as readout. This proposed strategy displays excellent discrimination ability for three phenylenediamines and may open new applications of MOFs in environmental science.
2022, 33(4): 2086-2090
doi: 10.1016/j.cclet.2021.08.094
Abstract:
Alcohol consumption is a critical risk factor contributing to a verity of human diseases. The incidence of alcohol use disorder increases across adolescence in recent years. Accumulating line of evidence suggests that alcohol-induced changes of DNA cytosine methylation (5-methyl-2'-deoxycytidine, 5mC) in genomes play an important role in the development of diseases. However, systemic investigation of the effects of adolescent alcohol exposure on DNA and RNA modifications is still lacked. Especially, there hasn't been any report to study the effects of alcohol exposure on RNA modifications. Similar to DNA modifications, RNA modifications recently have been identified to function as new regulators in modulating numbers of biological processes. In the current study, we systematically investigated the effects of alcohol exposure on both DNA and RNA modifications in peripheral blood of adolescent rats by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed LC-ESI-MS/MS method enabled the sensitive and accurate determination of 2 DNA modifications and 12 RNA modifications. As for the alcohol exposure experiments, the adolescent rats were intraperitoneally injected with ethanol with an interval of one day for a total 14 days. The quantification results by LC-ESI-MS/MS analysis showed that adolescent alcohol exposure could alter both DNA and RNA modifications in peripheral blood. Specifically, we observed an overall decreased trend of RNA modifications. The discovery of the significant alteration of the levels of DNA and RNA modifications under alcohol exposure indicates that alcohol consumption may increase the risk of the incidence and development of diseases through dysregulating DNA and RNA modifications.
Alcohol consumption is a critical risk factor contributing to a verity of human diseases. The incidence of alcohol use disorder increases across adolescence in recent years. Accumulating line of evidence suggests that alcohol-induced changes of DNA cytosine methylation (5-methyl-2'-deoxycytidine, 5mC) in genomes play an important role in the development of diseases. However, systemic investigation of the effects of adolescent alcohol exposure on DNA and RNA modifications is still lacked. Especially, there hasn't been any report to study the effects of alcohol exposure on RNA modifications. Similar to DNA modifications, RNA modifications recently have been identified to function as new regulators in modulating numbers of biological processes. In the current study, we systematically investigated the effects of alcohol exposure on both DNA and RNA modifications in peripheral blood of adolescent rats by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed LC-ESI-MS/MS method enabled the sensitive and accurate determination of 2 DNA modifications and 12 RNA modifications. As for the alcohol exposure experiments, the adolescent rats were intraperitoneally injected with ethanol with an interval of one day for a total 14 days. The quantification results by LC-ESI-MS/MS analysis showed that adolescent alcohol exposure could alter both DNA and RNA modifications in peripheral blood. Specifically, we observed an overall decreased trend of RNA modifications. The discovery of the significant alteration of the levels of DNA and RNA modifications under alcohol exposure indicates that alcohol consumption may increase the risk of the incidence and development of diseases through dysregulating DNA and RNA modifications.
2022, 33(4): 2091-2095
doi: 10.1016/j.cclet.2021.08.027
Abstract:
Foodborne pathogenic bacteria have been considered as a major risk factor for food safety. It is of great significance to carry out in-field screening of pathogenic bacteria to prevent the outbreaks of foodborne diseases. In this study, a portable lab-on-a-disc platform with a microfluidic disc was developed for rapid and automatic detection of Salmonella typhimurium using a nickel nanowire (NiNW) net for effective separation of target bacteria, horseradish peroxidase nanoflowers (HRP NFs) for efficient amplification of biological signals, and a self-developed smartphone APP for accurate analysis of colorimetric images. First, the microfluidic disc was preloaded with reagents and samples and centrifuged to form one bacterial sample column, one immune NiNW column, one HRP NF column, two washing buffer columns and one tetramethylbenzidine (TMB) column, which were separated by air gaps. Then, a rotatable magnetic field was specifically developed to assemble the NiNWs into a net, which was automatically controlled by a stepped motor to successively pass through the sample column for specific capture of target bacteria, the HRP NF column for specific label of target bacteria, the washing columns for effective removal of sample background and non-specific binding NFs, and the TMB column for colorimetric determination of target bacteria. The color change of TMB from colorless to blue was finally analyzed using the smartphone APP to quantitatively determine the target bacteria. This lab-on-a-disc platform could detect Salmonella typhimurium from 5.6×101 CFU/20 μL to 5.6×105 CFU/20 μL in 1 h with a lower detection limit of 56 CFU/20 μL. The recovery of target bacteria in spiked chicken samples ranged from 97.5% to 101.8%. This portable platform integrating separation, labeling, washing, catalysis and detection onto a single disc is featured with automatic operation, fast reaction, and small size and has shown its potential for in-field detection of foodborne pathogens.
Foodborne pathogenic bacteria have been considered as a major risk factor for food safety. It is of great significance to carry out in-field screening of pathogenic bacteria to prevent the outbreaks of foodborne diseases. In this study, a portable lab-on-a-disc platform with a microfluidic disc was developed for rapid and automatic detection of Salmonella typhimurium using a nickel nanowire (NiNW) net for effective separation of target bacteria, horseradish peroxidase nanoflowers (HRP NFs) for efficient amplification of biological signals, and a self-developed smartphone APP for accurate analysis of colorimetric images. First, the microfluidic disc was preloaded with reagents and samples and centrifuged to form one bacterial sample column, one immune NiNW column, one HRP NF column, two washing buffer columns and one tetramethylbenzidine (TMB) column, which were separated by air gaps. Then, a rotatable magnetic field was specifically developed to assemble the NiNWs into a net, which was automatically controlled by a stepped motor to successively pass through the sample column for specific capture of target bacteria, the HRP NF column for specific label of target bacteria, the washing columns for effective removal of sample background and non-specific binding NFs, and the TMB column for colorimetric determination of target bacteria. The color change of TMB from colorless to blue was finally analyzed using the smartphone APP to quantitatively determine the target bacteria. This lab-on-a-disc platform could detect Salmonella typhimurium from 5.6×101 CFU/20 μL to 5.6×105 CFU/20 μL in 1 h with a lower detection limit of 56 CFU/20 μL. The recovery of target bacteria in spiked chicken samples ranged from 97.5% to 101.8%. This portable platform integrating separation, labeling, washing, catalysis and detection onto a single disc is featured with automatic operation, fast reaction, and small size and has shown its potential for in-field detection of foodborne pathogens.
2022, 33(4): 2096-2100
doi: 10.1016/j.cclet.2021.08.041
Abstract:
Colorectal cancer (CRC) is still the leading cause of cancer death worldwide, but the clinical effect of drug therapy such as irinotecan is not an ideal way at present. In recent years, probiotics have attracted much attention, and the combination of probiotics may play an important role in the prevention and treatment of CRC. This work proposed a cellular chip-MS system, to study the synergistic effects of probiotic Lactobacillus rhamnosus GG (L.GG) and irinotecan on HCT116 cells by cell viability and on-line mass spectrometry (MS) analysis. The double-layer chip sandwiched with a polycarbonate membrane can co-culture HCT116 cells and L.GG. And the solid phase microextraction chip can be used for desalination and concentration. Finally, the extracted chemicals were entered the electrospray ionization quadrupole time-of-flight MS to detect irinotecan metabolites. The results showed that with the increasing concentration of co-cultured L.GG, the percentage of living HCT116 cells decreased, but the relative amount of metabolized SN-38 by HCT116 cells increased. Therefore, the microfluidic system can be used to detect and monitor the synergistic effect of irinotecan-L.GG combination on HCT116 cells. In summary, our study provided experimental evidence for the first time with potential applications of irinotecan-L.GG combination in CRC treatment, and the cellular chip-MS system as a powerful tool can be used in the experiments of probiotics as new drugs.
Colorectal cancer (CRC) is still the leading cause of cancer death worldwide, but the clinical effect of drug therapy such as irinotecan is not an ideal way at present. In recent years, probiotics have attracted much attention, and the combination of probiotics may play an important role in the prevention and treatment of CRC. This work proposed a cellular chip-MS system, to study the synergistic effects of probiotic Lactobacillus rhamnosus GG (L.GG) and irinotecan on HCT116 cells by cell viability and on-line mass spectrometry (MS) analysis. The double-layer chip sandwiched with a polycarbonate membrane can co-culture HCT116 cells and L.GG. And the solid phase microextraction chip can be used for desalination and concentration. Finally, the extracted chemicals were entered the electrospray ionization quadrupole time-of-flight MS to detect irinotecan metabolites. The results showed that with the increasing concentration of co-cultured L.GG, the percentage of living HCT116 cells decreased, but the relative amount of metabolized SN-38 by HCT116 cells increased. Therefore, the microfluidic system can be used to detect and monitor the synergistic effect of irinotecan-L.GG combination on HCT116 cells. In summary, our study provided experimental evidence for the first time with potential applications of irinotecan-L.GG combination in CRC treatment, and the cellular chip-MS system as a powerful tool can be used in the experiments of probiotics as new drugs.
2022, 33(4): 2101-2104
doi: 10.1016/j.cclet.2021.08.047
Abstract:
Exosomal microRNA (miRNA) is an ideal candidate of noninvasive biomarker for the early diagnosis of cancer. Sensitive and accurate sensing of abnormal exosomal miRNA plays essential role for clinical promotion due to its close correlation with tumor proliferation and progression. Herein, a microfluidic surface-enhanced Raman scattering (SERS) sensor was proposed for an on-line detection of exosomal miRNA based on rolling circle amplification (RCA) and tyramine signal amplification (TSA) strategy. The microfluidic chip consists of a magnetic enrichment chamber, a serpentine fluidic mixer and a plasmonic SERS substrate functionalized with capture probes. The released miRNA activates the capture probe, triggers RCA reaction, and generates a large number of single-stranded DNA products to drive the catalysis of nanotags deposition via TSA, producing numerous phot spotsq to enhance the SERS signals. In merit of the microfluidics chip and nucleic acid-tyramine cascade amplification, the developed SERS sensor significantly improves the sensitivity for the exosomal miRNA assay, resulting in a limit of detection (LOD) as low as 1 pmol/L and can be successfully applied in the analysis of exosomes secreted from breast tumor cells, which demonstrates the potential utility in practical applications.
Exosomal microRNA (miRNA) is an ideal candidate of noninvasive biomarker for the early diagnosis of cancer. Sensitive and accurate sensing of abnormal exosomal miRNA plays essential role for clinical promotion due to its close correlation with tumor proliferation and progression. Herein, a microfluidic surface-enhanced Raman scattering (SERS) sensor was proposed for an on-line detection of exosomal miRNA based on rolling circle amplification (RCA) and tyramine signal amplification (TSA) strategy. The microfluidic chip consists of a magnetic enrichment chamber, a serpentine fluidic mixer and a plasmonic SERS substrate functionalized with capture probes. The released miRNA activates the capture probe, triggers RCA reaction, and generates a large number of single-stranded DNA products to drive the catalysis of nanotags deposition via TSA, producing numerous phot spotsq to enhance the SERS signals. In merit of the microfluidics chip and nucleic acid-tyramine cascade amplification, the developed SERS sensor significantly improves the sensitivity for the exosomal miRNA assay, resulting in a limit of detection (LOD) as low as 1 pmol/L and can be successfully applied in the analysis of exosomes secreted from breast tumor cells, which demonstrates the potential utility in practical applications.
2022, 33(4): 2105-2110
doi: 10.1016/j.cclet.2021.08.054
Abstract:
In this study, novel iron-doped biochar (Fe-BC) was produced using a simple method, and it was used as an H2O2 activator for tetracycline (TC) degradation. Generally, iron loading can improve the separation performance and reactivity of biochar (BC). In the Fe-BC/H2O2 system, 92% of the TC was removed within 30 min with the apparent rate constant (kobs) of 0.155 min−1, which was 23.85 times that in the case of the BC/H2O2 system (0.0065 min−1). The effects of the H2O2 and Fe-BC dosage, initial pH, and TC concentration on the TC removal were investigated. The radical quenching and electron paramagnetic resonance (EPR) measurements demonstrated that the removal of TC using the Fe-BC/H2O2 process involved both radical (•OH and O2−•) and non-radical pathways (1O2 and electron transfer). In addition, the performance of the catalyst was also affected by the persistent free radicals (PFRs) and defective sites on the catalyst. Moreover, the degradation pathways of TC were proposed according to the intermediate products detected by LC-MS and the ecotoxicity of intermediates was evaluated. Finally, the Fe-BC/H2O2 showed high resistance to inorganic anions and natural organic matter in aquatic environments. Overall, Fe-BC is expected to be an economic and highly efficient heterogeneous Fenton catalyst for removing the organic contaminants in wastewater.
In this study, novel iron-doped biochar (Fe-BC) was produced using a simple method, and it was used as an H2O2 activator for tetracycline (TC) degradation. Generally, iron loading can improve the separation performance and reactivity of biochar (BC). In the Fe-BC/H2O2 system, 92% of the TC was removed within 30 min with the apparent rate constant (kobs) of 0.155 min−1, which was 23.85 times that in the case of the BC/H2O2 system (0.0065 min−1). The effects of the H2O2 and Fe-BC dosage, initial pH, and TC concentration on the TC removal were investigated. The radical quenching and electron paramagnetic resonance (EPR) measurements demonstrated that the removal of TC using the Fe-BC/H2O2 process involved both radical (•OH and O2−•) and non-radical pathways (1O2 and electron transfer). In addition, the performance of the catalyst was also affected by the persistent free radicals (PFRs) and defective sites on the catalyst. Moreover, the degradation pathways of TC were proposed according to the intermediate products detected by LC-MS and the ecotoxicity of intermediates was evaluated. Finally, the Fe-BC/H2O2 showed high resistance to inorganic anions and natural organic matter in aquatic environments. Overall, Fe-BC is expected to be an economic and highly efficient heterogeneous Fenton catalyst for removing the organic contaminants in wastewater.
2022, 33(4): 2111-2116
doi: 10.1016/j.cclet.2021.08.053
Abstract:
Developing photocatalyst with high activity, superior stability and prominent selectivity for CO2 conversion is of great importance for the target of carbon neutralization. Herein, 3D dahlia-like NiAl-LDH/CdS heterosystem is developed through in-situ decoration of exfoliated CdS nanosheets on the scaffold of NiAl-LDH and the on-spot self-assembly. The formation of a hierarchical architecture collaborating with well-defined 2D/2D interfacial interaction is constructed by optimizing the ratio of CdS integrated in the formation of the heterojunction. The light-harvesting capacity of NiAl-LDH/CdS is improved by this unique scaffold, and the charge transfer between NiAl-LDH and CdS is effectively facilitated by virtue of the unique 2D/2D interface. As a result, the 3D hierarchical NiAl-LDH/CdS heterosystem presents 12.45µmol g−1 h−1 of CO production (3.3 and 1.6 folds of pristine NiAl-LDH and CdS) with 96% selectivity and superior stability. This 3D hierarchical design collaborating with 2D/2D interfacial interaction provides a new avenue to develop ideal catalysts for artificial photosynthesis.
Developing photocatalyst with high activity, superior stability and prominent selectivity for CO2 conversion is of great importance for the target of carbon neutralization. Herein, 3D dahlia-like NiAl-LDH/CdS heterosystem is developed through in-situ decoration of exfoliated CdS nanosheets on the scaffold of NiAl-LDH and the on-spot self-assembly. The formation of a hierarchical architecture collaborating with well-defined 2D/2D interfacial interaction is constructed by optimizing the ratio of CdS integrated in the formation of the heterojunction. The light-harvesting capacity of NiAl-LDH/CdS is improved by this unique scaffold, and the charge transfer between NiAl-LDH and CdS is effectively facilitated by virtue of the unique 2D/2D interface. As a result, the 3D hierarchical NiAl-LDH/CdS heterosystem presents 12.45µmol g−1 h−1 of CO production (3.3 and 1.6 folds of pristine NiAl-LDH and CdS) with 96% selectivity and superior stability. This 3D hierarchical design collaborating with 2D/2D interfacial interaction provides a new avenue to develop ideal catalysts for artificial photosynthesis.
2022, 33(4): 2117-2120
doi: 10.1016/j.cclet.2021.08.080
Abstract:
Water-caused luminescence quenching is a well-known and intractable issue for luminescence lanthanide complexes, greatly confining their broad application as sensing and displaying devices in water system. Herein, an anionic and coordination-saturated lanthanide complex with a nanosheet-like structure has been prepared. It exhibits excellent photophysical properties both in solid state and in aqueous suspension. Noteworthily, a 13% improvement for sensitization efficiency from organic ligand to central lanthanide ion has been realized, indicating an exceptional phenomenon of water-induced luminescence improvement which is rarely reported previously. Moreover, the aqueous suspension of as-prepared luminophore could act as a chemo-sensor responding to various organic solvents in water. Both of water-induced luminescence improvement and extended sensing behavior in this work provide a new platform for developing highly performant and practical luminescent materials in the water system.
Water-caused luminescence quenching is a well-known and intractable issue for luminescence lanthanide complexes, greatly confining their broad application as sensing and displaying devices in water system. Herein, an anionic and coordination-saturated lanthanide complex with a nanosheet-like structure has been prepared. It exhibits excellent photophysical properties both in solid state and in aqueous suspension. Noteworthily, a 13% improvement for sensitization efficiency from organic ligand to central lanthanide ion has been realized, indicating an exceptional phenomenon of water-induced luminescence improvement which is rarely reported previously. Moreover, the aqueous suspension of as-prepared luminophore could act as a chemo-sensor responding to various organic solvents in water. Both of water-induced luminescence improvement and extended sensing behavior in this work provide a new platform for developing highly performant and practical luminescent materials in the water system.
2022, 33(4): 2121-2124
doi: 10.1016/j.cclet.2021.08.085
Abstract:
In this study, Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst was synthesized by in-situ photo-reducing of silver on S, N-TiO2-x nanocomposite and used to degrade bisphenol A (BPA) through heterogeneous activation of potassium peroxymonosulfate (PMS) under visible-light illumination. The structure, physicochemical property, morphology, and electronic property were evalutated by X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectra (XPS), high-resolution transmission electron microscopy (HR-TEM), UV–vis diffuse reflectance spectra (UV-vis DRS), electron paramagnetic resonance (EPR) spectrum. Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst exhibited 2.4 times higher activity for the synergetic degradation of BPA than that of its counterpart, and 48.73% mineralization rate of BPA also achieved. It was ascribed to the uniformly-dispersed metallic Ag atoms as the active site for accelerating the migration rate of photo-generated carrier for generation of high reactive radicals. The EPR experiments indicated that SO4•‒ and •OH was jointly involved in BPA degradation.
In this study, Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst was synthesized by in-situ photo-reducing of silver on S, N-TiO2-x nanocomposite and used to degrade bisphenol A (BPA) through heterogeneous activation of potassium peroxymonosulfate (PMS) under visible-light illumination. The structure, physicochemical property, morphology, and electronic property were evalutated by X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectra (XPS), high-resolution transmission electron microscopy (HR-TEM), UV–vis diffuse reflectance spectra (UV-vis DRS), electron paramagnetic resonance (EPR) spectrum. Ag0.23/(S1.66-N1.91/TiO2-x) single-atom photocatalyst exhibited 2.4 times higher activity for the synergetic degradation of BPA than that of its counterpart, and 48.73% mineralization rate of BPA also achieved. It was ascribed to the uniformly-dispersed metallic Ag atoms as the active site for accelerating the migration rate of photo-generated carrier for generation of high reactive radicals. The EPR experiments indicated that SO4•‒ and •OH was jointly involved in BPA degradation.
2022, 33(4): 2125-2128
doi: 10.1016/j.cclet.2021.10.087
Abstract:
The difficulty in Fe(Ⅲ)/Fe(Ⅱ) conversion in the Fe(Ⅲ)/peroxymonosulfate (PMS) process limits its efficiency and application. Herein, l-cysteine (Cys), a green natural organic ligand with reducing capability, was innovatively introduced into Fe(Ⅲ)/PMS to construct an excellent Cys/Fe(Ⅲ)/PMS process. The Cys/Fe(Ⅲ)/PMS process, at room temperature, can degrade a variety of organic contaminants, including dyes, phenolic compounds, and pharmaceuticals. In subsequent experiments with acid orange 7 (AO7), the AO7 degradation efficiency followed pseudo-first-order kinetic which exhibited an initial "fast stage" and a second "slow stage". The rate constant values ranged depending on the initial Cys, Fe(Ⅲ), PMS, and AO7 concentrations, reaction temperature, and pH values. In addition, the presence of Cl−, NO3−, and SO42− had negligible impact while HCO3− and humic acid inhibited the degradation of AO7. Furthermore, radical scavenger experiments and methyl phenyl sulfoxide (PMSO) transformation assay indicated that sulfate radical, hydroxyl radical, and ferryl ion (Fe(Ⅳ)) were the dominant reactive species involved in the Cys/Fe(Ⅲ)/PMS process. Finally, based on the results of gas chromatography-mass spectrometry, several AO7 degradation pathways, including N=N cleavage, hydroxylation, and ring opening were proposed. This study provided a new insight to improve the efficiency of Fe(Ⅲ)/PMS process by accelerating Fe(Ⅲ)/Fe(Ⅱ) cycle with Cys.
The difficulty in Fe(Ⅲ)/Fe(Ⅱ) conversion in the Fe(Ⅲ)/peroxymonosulfate (PMS) process limits its efficiency and application. Herein, l-cysteine (Cys), a green natural organic ligand with reducing capability, was innovatively introduced into Fe(Ⅲ)/PMS to construct an excellent Cys/Fe(Ⅲ)/PMS process. The Cys/Fe(Ⅲ)/PMS process, at room temperature, can degrade a variety of organic contaminants, including dyes, phenolic compounds, and pharmaceuticals. In subsequent experiments with acid orange 7 (AO7), the AO7 degradation efficiency followed pseudo-first-order kinetic which exhibited an initial "fast stage" and a second "slow stage". The rate constant values ranged depending on the initial Cys, Fe(Ⅲ), PMS, and AO7 concentrations, reaction temperature, and pH values. In addition, the presence of Cl−, NO3−, and SO42− had negligible impact while HCO3− and humic acid inhibited the degradation of AO7. Furthermore, radical scavenger experiments and methyl phenyl sulfoxide (PMSO) transformation assay indicated that sulfate radical, hydroxyl radical, and ferryl ion (Fe(Ⅳ)) were the dominant reactive species involved in the Cys/Fe(Ⅲ)/PMS process. Finally, based on the results of gas chromatography-mass spectrometry, several AO7 degradation pathways, including N=N cleavage, hydroxylation, and ring opening were proposed. This study provided a new insight to improve the efficiency of Fe(Ⅲ)/PMS process by accelerating Fe(Ⅲ)/Fe(Ⅱ) cycle with Cys.
2022, 33(4): 2129-2133
doi: 10.1016/j.cclet.2021.07.063
Abstract:
Transition metal-based bimetallic oxides can effectively activate peroxymonosulfate (PMS) for the degradation of organic contaminants, which may be attributed to the enhanced electron transfer efficiency between transition metals. Here, we investigated the high-efficiency catalytic activation reaction of PMS on a well-defined bimetallic Fe-Mn nanocomposite (BFMN) catalyst. The surface topography and chemical information of BFMN were simultaneously mapped with nanoscale resolution. Rhodamine B (RhB, as a model pollutant) was used to evaluate the oxidation activity of PMS activation system. The maximum absorption peak of RhB obviously blue shifted from 554 nm to 501 nm, and decreased sharply to disappear completely within 60 min. The removal performance is better than most of the reported single transition metal oxide. X-ray photoelectron spectroscopy (XPS) imaging of the BFMN electronic structure after catalytic activation confirmed that the accelerated internal electron transfer is mainly caused by the synergy effect of Mn and Fe sites at the catalysis boundary. The outstanding ability of BFMN for PMS chemical adsorption and activation may attribute to the enhanced covalency and reactivity of Mn-O. These results of this study can advance understandings on the origins of bimetallic oxides activity for PMS activation and developing the efficient metal oxide catalysts in real practice.
Transition metal-based bimetallic oxides can effectively activate peroxymonosulfate (PMS) for the degradation of organic contaminants, which may be attributed to the enhanced electron transfer efficiency between transition metals. Here, we investigated the high-efficiency catalytic activation reaction of PMS on a well-defined bimetallic Fe-Mn nanocomposite (BFMN) catalyst. The surface topography and chemical information of BFMN were simultaneously mapped with nanoscale resolution. Rhodamine B (RhB, as a model pollutant) was used to evaluate the oxidation activity of PMS activation system. The maximum absorption peak of RhB obviously blue shifted from 554 nm to 501 nm, and decreased sharply to disappear completely within 60 min. The removal performance is better than most of the reported single transition metal oxide. X-ray photoelectron spectroscopy (XPS) imaging of the BFMN electronic structure after catalytic activation confirmed that the accelerated internal electron transfer is mainly caused by the synergy effect of Mn and Fe sites at the catalysis boundary. The outstanding ability of BFMN for PMS chemical adsorption and activation may attribute to the enhanced covalency and reactivity of Mn-O. These results of this study can advance understandings on the origins of bimetallic oxides activity for PMS activation and developing the efficient metal oxide catalysts in real practice.
2022, 33(4): 2134-2138
doi: 10.1016/j.cclet.2021.09.012
Abstract:
Metal-organic frameworks (MOFs) show great potential for various applications, but many of them suffer from the drawbacks of hydrolysis propensity and poor processability. Herein, we employ polymers of intrinsic microporosity (PIMs) with hydrophobic pores to decorate MOFs toward substantially improved water stability and shapeability. Through simple PIM-1 decoration, the sub-5 nm polymer layers can be uniformly deposited on MOF surfaces with almost no deterioration in porosity. Owing to the existence of superhydrophobic coating and the obstruction of water entrance into MOFs, the PIM-1 coated CuBTC exhibits impressive water resistance and excellent pore preservation ability after exposure in water, even in acidic and alkaline solutions. Moreover, polymer decoration improves the processability of MOFs, while various MOF/PIM-1 bulk wafers and oil-water separators can be obtained straightforwardly.
Metal-organic frameworks (MOFs) show great potential for various applications, but many of them suffer from the drawbacks of hydrolysis propensity and poor processability. Herein, we employ polymers of intrinsic microporosity (PIMs) with hydrophobic pores to decorate MOFs toward substantially improved water stability and shapeability. Through simple PIM-1 decoration, the sub-5 nm polymer layers can be uniformly deposited on MOF surfaces with almost no deterioration in porosity. Owing to the existence of superhydrophobic coating and the obstruction of water entrance into MOFs, the PIM-1 coated CuBTC exhibits impressive water resistance and excellent pore preservation ability after exposure in water, even in acidic and alkaline solutions. Moreover, polymer decoration improves the processability of MOFs, while various MOF/PIM-1 bulk wafers and oil-water separators can be obtained straightforwardly.
2022, 33(4): 2139-2142
doi: 10.1016/j.cclet.2021.08.038
Abstract:
We report the first disubstituted hetero-ten-vertex closo cluster [(CrGe9)Cr2(CO)13]4- with three adjacent Cr(CO)n units adopting both η5 and η1 coordination modes, which was synthesized through the reaction of "KGe1.67" with (MeCN)3Cr(CO)3 and Cr(CO)6 in ethylenediamine (en) solution. In contrast to the η1-Cr atoms forming localized two-center two-elelctron (2c-2e) Cr-Ge bonds, the hetero atom η5-Cr exhibits versatile bonding mechanisms including three 5c-2e and five 8c-2e delocalized bonds which account for Hückel aromaticity. Intricate multi-center bonding patterns delineate the multiple local σ-aromatic characters of the title cluster displaying explicit spherical aromaticity.
We report the first disubstituted hetero-ten-vertex closo cluster [(CrGe9)Cr2(CO)13]4- with three adjacent Cr(CO)n units adopting both η5 and η1 coordination modes, which was synthesized through the reaction of "KGe1.67" with (MeCN)3Cr(CO)3 and Cr(CO)6 in ethylenediamine (en) solution. In contrast to the η1-Cr atoms forming localized two-center two-elelctron (2c-2e) Cr-Ge bonds, the hetero atom η5-Cr exhibits versatile bonding mechanisms including three 5c-2e and five 8c-2e delocalized bonds which account for Hückel aromaticity. Intricate multi-center bonding patterns delineate the multiple local σ-aromatic characters of the title cluster displaying explicit spherical aromaticity.
2022, 33(4): 2143-2146
doi: 10.1016/j.cclet.2021.08.098
Abstract:
Owing to the diversity of structure and potential applications in the field of electrics, sensors, and light-emitting diodes, lead halide perovskites have attracted great attention in recent years. Especially those lead halide perovskites with non-centrosymmetric crystal structures usually exhibit nonlinear optical (NLO) characteristics, which may endow them photoelectricity switching functionality. In this work, a lead-based hybrid organic-inorganic perovskite (HOIP) material, trimethyliodomethylammonium lead trichloride (TMIM·PbCl3), is obtained on the basis of tetramethylammonium lead chloride through halogen substitution on the cation part. It shows dual-phase-transition behavior around 345 and 358 K, which is significantly improved. TMIM·PbCl3 crystallizes in the chiral space group, P212121, and shows a well-defined second harmonic generation (SHG) response, and good switching endurance, which makes it an excellent candidate for SHG switching material. This work highlights the importance of halogen substitution for crystal engineering and may pave way for the further exploration of the optoelectronic devices.
Owing to the diversity of structure and potential applications in the field of electrics, sensors, and light-emitting diodes, lead halide perovskites have attracted great attention in recent years. Especially those lead halide perovskites with non-centrosymmetric crystal structures usually exhibit nonlinear optical (NLO) characteristics, which may endow them photoelectricity switching functionality. In this work, a lead-based hybrid organic-inorganic perovskite (HOIP) material, trimethyliodomethylammonium lead trichloride (TMIM·PbCl3), is obtained on the basis of tetramethylammonium lead chloride through halogen substitution on the cation part. It shows dual-phase-transition behavior around 345 and 358 K, which is significantly improved. TMIM·PbCl3 crystallizes in the chiral space group, P212121, and shows a well-defined second harmonic generation (SHG) response, and good switching endurance, which makes it an excellent candidate for SHG switching material. This work highlights the importance of halogen substitution for crystal engineering and may pave way for the further exploration of the optoelectronic devices.
2022, 33(4): 2147-2150
doi: 10.1016/j.cclet.2021.08.079
Abstract:
Azulene, one of representative nonbenzenoid aromatic hydrocarbons, exhibits unique molecular structure and distinctive physical and chemical properties. Herein, azulenoisoindigo (AzII), an azulene-based isoindigo analogue, is designed and synthesized, which has a twisted molecular backbone and R/S-isomers in single crystals. Interestingly, AzII shows the characteristics of both isoindigo and azulene, such as reversible redox behavior and reversible proton responsiveness. UV-vis-NIR, 1H NMR and electron paramagnetic resonance (EPR) measurements were carried out to get insights into the possible mechanism of the proton-responsive property of AzII. The results demonstrated that only one azulenyl moiety of molecule of AzII was protonated and deprotonated, and the protonated AzII can be further oxidized to form azulenium cation radicals.
Azulene, one of representative nonbenzenoid aromatic hydrocarbons, exhibits unique molecular structure and distinctive physical and chemical properties. Herein, azulenoisoindigo (AzII), an azulene-based isoindigo analogue, is designed and synthesized, which has a twisted molecular backbone and R/S-isomers in single crystals. Interestingly, AzII shows the characteristics of both isoindigo and azulene, such as reversible redox behavior and reversible proton responsiveness. UV-vis-NIR, 1H NMR and electron paramagnetic resonance (EPR) measurements were carried out to get insights into the possible mechanism of the proton-responsive property of AzII. The results demonstrated that only one azulenyl moiety of molecule of AzII was protonated and deprotonated, and the protonated AzII can be further oxidized to form azulenium cation radicals.
2022, 33(4): 2151-2154
doi: 10.1016/j.cclet.2021.08.124
Abstract:
Herein, we presented a novel biodegradable copolymer via the chain extending reaction of poly(p-dioxanone)-co-poly(2-(2-hydroxyethoxy) benzoate) (PPDO-co-PDHB) prepolymer with hexamethylene diisocyanate (HDI) as a chain extender. The structures and molecular weight of PPDO-co-PDHB prepolymer and PPDO-co-PDHB-PU chain-extended copolymer are characterized via hydrogen nuclear magnetic resonance spectroscopy (1H NMR) and viscosity test. The relationship between the molecular structures and properties of the chain-extended copolymers is established. The PPDO-co-PDHB-PU copolymers possess a better thermal stability comparing with the PPDO homopolymer. The study of mechanical properties shows that the elongation-at-break of PPDO-co-PDHB-PU is much higher than that of PPDO. The investigation of hydrolytic degradation behaviors indicates the degradation rate of PPDO can be controlled by adjusting the PDHB compositions, and proves that chain-extended copolymers exhibit an excellent hydrolytic stability being better than that of PPDO.
Herein, we presented a novel biodegradable copolymer via the chain extending reaction of poly(p-dioxanone)-co-poly(2-(2-hydroxyethoxy) benzoate) (PPDO-co-PDHB) prepolymer with hexamethylene diisocyanate (HDI) as a chain extender. The structures and molecular weight of PPDO-co-PDHB prepolymer and PPDO-co-PDHB-PU chain-extended copolymer are characterized via hydrogen nuclear magnetic resonance spectroscopy (1H NMR) and viscosity test. The relationship between the molecular structures and properties of the chain-extended copolymers is established. The PPDO-co-PDHB-PU copolymers possess a better thermal stability comparing with the PPDO homopolymer. The study of mechanical properties shows that the elongation-at-break of PPDO-co-PDHB-PU is much higher than that of PPDO. The investigation of hydrolytic degradation behaviors indicates the degradation rate of PPDO can be controlled by adjusting the PDHB compositions, and proves that chain-extended copolymers exhibit an excellent hydrolytic stability being better than that of PPDO.
2022, 33(4): 2155-2158
doi: 10.1016/j.cclet.2021.09.007
Abstract:
Carbon nanotube-based (CNT-based) interfacial evaporation material is one of the most potential materials for solar desalination. Here, we studied the evaporation rate of the CNT-based membranes with different hydrophilic and hydrophobic chemical modified surfaces using molecular dynamic simulations. We found that the hydrogen bonding density among water molecules at the interface is a key factor in enhancing the evaporation rate. For a hydrophilic CNT-based membrane, the strong interactions between the membrane outer surface and the water molecules can destroy the water-water hydrogen bonding interactions at the interface, resulting in the reduction of the hydrogen bonding density, leading to an enhancement effect in evaporation rate. We also found that there is an optimal thickness for evaporation membrane. These findings could provide some theoretical guidance for designing and exploring advanced CNT-based systems with more beneficial performance in water desalination.
Carbon nanotube-based (CNT-based) interfacial evaporation material is one of the most potential materials for solar desalination. Here, we studied the evaporation rate of the CNT-based membranes with different hydrophilic and hydrophobic chemical modified surfaces using molecular dynamic simulations. We found that the hydrogen bonding density among water molecules at the interface is a key factor in enhancing the evaporation rate. For a hydrophilic CNT-based membrane, the strong interactions between the membrane outer surface and the water molecules can destroy the water-water hydrogen bonding interactions at the interface, resulting in the reduction of the hydrogen bonding density, leading to an enhancement effect in evaporation rate. We also found that there is an optimal thickness for evaporation membrane. These findings could provide some theoretical guidance for designing and exploring advanced CNT-based systems with more beneficial performance in water desalination.
2022, 33(4): 2159-2164
doi: 10.1016/j.cclet.2021.10.056
Abstract:
Pharmaceutical salt formation is the most preferred and effective method to enhance the physicochemical properties of APIs. The aim of the study was to design and synthesize a series of new salts to improve the solubility of Imatinib (IM). Two stable salts with malonic acid (S1) and citric acid (S5), one metastable salt with fumaric acid (S2), two unstable salts with citric acid (S3, S4) were obtained for the first time. Single crystal and powder X-ray diffraction, Fourier transform infrared, differential scanning calorimetry, and thermogravimetric analysis were used to characterize the novel salts. The solubility and stability of the solid were also evaluated, and three salts (S1, S2, S5) had a more than 20 folds of solubility and a faster dissolution rate improved as compared to the pure drug in water and pH 6.8 buffer, respectively.
Pharmaceutical salt formation is the most preferred and effective method to enhance the physicochemical properties of APIs. The aim of the study was to design and synthesize a series of new salts to improve the solubility of Imatinib (IM). Two stable salts with malonic acid (S1) and citric acid (S5), one metastable salt with fumaric acid (S2), two unstable salts with citric acid (S3, S4) were obtained for the first time. Single crystal and powder X-ray diffraction, Fourier transform infrared, differential scanning calorimetry, and thermogravimetric analysis were used to characterize the novel salts. The solubility and stability of the solid were also evaluated, and three salts (S1, S2, S5) had a more than 20 folds of solubility and a faster dissolution rate improved as compared to the pure drug in water and pH 6.8 buffer, respectively.
2022, 33(4): 2165-2170
doi: 10.1016/j.cclet.2021.10.051
Abstract:
Metal skeletons, such as Nickel Foam (NF) has attracted worldwide interests as stable host for lithium metal anode because of its high stability, large specific surface area and high conductivity. However, most metal skeletons have lithophobic surface and uneven current distribution that result in sporadic lithium nucleation and uncontrolled dendrites growth. Herein, we describe a sequential immersing strategy to generate interwoven Nickel(Ⅱ)-dimethylglyoxime (Ni-DMG) nanowires at NF to obtain composite skeleton (NDNF), which can be used as an stable host for Li metal storage. The Ni-DMG has proved effective to realize uniform lithium nucleation and dendrite-free lithium deposition. Combing with the three dimensional (3D) hierarchical porous structure, the composite host shows a significantly improved coulombic efficiency (CE) than pristine commercial nickel foam. Moreover, the corresponding Li||Li symmetrical cells can run more than 700 h with low voltage hysteresis 22 mV at 1.0 mA/cm2, and Li@NDNF||LiFePO4 full-cell exhibits a high capacity retention of 82.03% at 1.0 C during 630 cycles. These results proved the effectiveness of metal-organic complexes in governing Li metal growth and can be employed as a new strategy for dendrite-free Li metal anode and safe Li metal batteries (LMBs).
Metal skeletons, such as Nickel Foam (NF) has attracted worldwide interests as stable host for lithium metal anode because of its high stability, large specific surface area and high conductivity. However, most metal skeletons have lithophobic surface and uneven current distribution that result in sporadic lithium nucleation and uncontrolled dendrites growth. Herein, we describe a sequential immersing strategy to generate interwoven Nickel(Ⅱ)-dimethylglyoxime (Ni-DMG) nanowires at NF to obtain composite skeleton (NDNF), which can be used as an stable host for Li metal storage. The Ni-DMG has proved effective to realize uniform lithium nucleation and dendrite-free lithium deposition. Combing with the three dimensional (3D) hierarchical porous structure, the composite host shows a significantly improved coulombic efficiency (CE) than pristine commercial nickel foam. Moreover, the corresponding Li||Li symmetrical cells can run more than 700 h with low voltage hysteresis 22 mV at 1.0 mA/cm2, and Li@NDNF||LiFePO4 full-cell exhibits a high capacity retention of 82.03% at 1.0 C during 630 cycles. These results proved the effectiveness of metal-organic complexes in governing Li metal growth and can be employed as a new strategy for dendrite-free Li metal anode and safe Li metal batteries (LMBs).
2022, 33(4): 2171-2177
doi: 10.1016/j.cclet.2021.09.014
Abstract:
Designing highly efficient non-precious based electrocatalysts for oxygen reduction reaction (ORR) is of significance for the rapid development of metal-air batteries. Herein, a hydrothermal-pyrolysis method is employed to fabricate Fe, N co-doped porous carbon materials as effective ORR electrocatalyst through adopting graphitic carbon nitride (g-C3N4) as both the self-sacrificial templates and N sources. The g-C3N4 provides a high concentration of unsaturated pyridine-type N to coordinate with iron to form Fe-N active sites. Through adjusting the Fe doping amounts, it is proved that appropriate Fe doping content is conducive to the construction of abundant defects and active sites of Fe-N. The as-prepared catalyst exhibits superior electrocatalytic ORR performance in alkaline media with half-wave potential (E1/2 = 0.82 V) and onset potential (Eonset = 0.95 V), equivalent to the commercial Pt/C catalyst. Moreover, there is almost no activity loss after 10 k continuous cyclic voltammetry cycles and methanol tolerance, indicating the excellent durability and superior methanol tolerance. Remarkably, when assembled as the cathode in a Zn-air battery, the device displays a power density of 99 mW/cm2, an open-circuit potential of 1.48 V and long-term discharge-charge cycling stability, indicating the promising potential to substitute the Pt catalyst for practical application.
Designing highly efficient non-precious based electrocatalysts for oxygen reduction reaction (ORR) is of significance for the rapid development of metal-air batteries. Herein, a hydrothermal-pyrolysis method is employed to fabricate Fe, N co-doped porous carbon materials as effective ORR electrocatalyst through adopting graphitic carbon nitride (g-C3N4) as both the self-sacrificial templates and N sources. The g-C3N4 provides a high concentration of unsaturated pyridine-type N to coordinate with iron to form Fe-N active sites. Through adjusting the Fe doping amounts, it is proved that appropriate Fe doping content is conducive to the construction of abundant defects and active sites of Fe-N. The as-prepared catalyst exhibits superior electrocatalytic ORR performance in alkaline media with half-wave potential (E1/2 = 0.82 V) and onset potential (Eonset = 0.95 V), equivalent to the commercial Pt/C catalyst. Moreover, there is almost no activity loss after 10 k continuous cyclic voltammetry cycles and methanol tolerance, indicating the excellent durability and superior methanol tolerance. Remarkably, when assembled as the cathode in a Zn-air battery, the device displays a power density of 99 mW/cm2, an open-circuit potential of 1.48 V and long-term discharge-charge cycling stability, indicating the promising potential to substitute the Pt catalyst for practical application.
2022, 33(4): 2178-2182
doi: 10.1016/j.cclet.2021.09.015
Abstract:
Conventional gels manifest monotonous swelling or shrinking performance upon immersing in solvents until reaching an equilibrium state. Recently, we discovered that the "hydrophobic hydrogels" prepared from hydrophobic polymer networks demonstrated dynamic swelling performance without equilibrium states. Upon water immersion, the gels expanded tremendously at the first stage until reaching a swelling peak; subsequently, the gels shrunk at an extremely slow rate. While this phenomenon endows the material with an unusual feature, more efforts are highly demanding for the full understanding of this performance. Herein, we systematically investigate the hydrophobic hydrogels' swelling kinetics by screening the organic solvent dependence, polymer effect, and temperature impact. It is revealed that the chemical structure of gels greatly influences the swelling kinetics. The higher the networks' hydrophobicity, the slower the swelling kinetics. Meanwhile, organic solvents demonstrate a limited effect on the dynamic swelling performance. Moreover, higher temperature significantly accelerates the whole volume change process. Based on the swelling performance, we further develop hydrogel-based soft devices with time-programmable two-dimensional and three-dimensional shape-shifting performances.
Conventional gels manifest monotonous swelling or shrinking performance upon immersing in solvents until reaching an equilibrium state. Recently, we discovered that the "hydrophobic hydrogels" prepared from hydrophobic polymer networks demonstrated dynamic swelling performance without equilibrium states. Upon water immersion, the gels expanded tremendously at the first stage until reaching a swelling peak; subsequently, the gels shrunk at an extremely slow rate. While this phenomenon endows the material with an unusual feature, more efforts are highly demanding for the full understanding of this performance. Herein, we systematically investigate the hydrophobic hydrogels' swelling kinetics by screening the organic solvent dependence, polymer effect, and temperature impact. It is revealed that the chemical structure of gels greatly influences the swelling kinetics. The higher the networks' hydrophobicity, the slower the swelling kinetics. Meanwhile, organic solvents demonstrate a limited effect on the dynamic swelling performance. Moreover, higher temperature significantly accelerates the whole volume change process. Based on the swelling performance, we further develop hydrogel-based soft devices with time-programmable two-dimensional and three-dimensional shape-shifting performances.
2022, 33(4): 2183-2187
doi: 10.1016/j.cclet.2021.09.010
Abstract:
The synthesis of high-value multi-carbon products through the electrochemical reduction of carbon monoxide (COER) is one of the promising avenues for carbon utilization and energy storage, in which searching for efficient electrocatalysts that exhibit moderate CO intermediate binding strength and low kinetic barrier for C-C coupling is a key issue. Herein, by means of comprehensive density functional theory (DFT) computations, we theoretically designed three synergistic coupling catalysts by co-doping transition metal (TM = Fe, Co and Ni) and boron (B) into the two-dimensional black phosphorene (BP), namely TM-B@BP for COER to C2 products. DFT computations and ab initio molecular dynamics simulations reveal the good stability and high feasibility of these proposed TM-B@BP catalysts for practical applications and future experimental synthesis. More interestingly, high-value ethylene (C2H4), ethane (C2H6) and ethanol (C2H5OH) products can be obtained on these three designed electrocatalysts with ultra-small limiting potentials (−0.20~−0.41 V) and low kinetic energy barriers of C-C coupling (0.52~0.91 eV). Meanwhile, the competitive one-carbon (C1) products and hydrogen evolution reaction can also be effectively suppressed. The promising activity and selectivity of these three designed electrocatalysts render them ideal candidates for CO electroreduction, thus providing a cost-effective opportunity to achieve a sustainable production of high value C2 chemicals and fuels.
The synthesis of high-value multi-carbon products through the electrochemical reduction of carbon monoxide (COER) is one of the promising avenues for carbon utilization and energy storage, in which searching for efficient electrocatalysts that exhibit moderate CO intermediate binding strength and low kinetic barrier for C-C coupling is a key issue. Herein, by means of comprehensive density functional theory (DFT) computations, we theoretically designed three synergistic coupling catalysts by co-doping transition metal (TM = Fe, Co and Ni) and boron (B) into the two-dimensional black phosphorene (BP), namely TM-B@BP for COER to C2 products. DFT computations and ab initio molecular dynamics simulations reveal the good stability and high feasibility of these proposed TM-B@BP catalysts for practical applications and future experimental synthesis. More interestingly, high-value ethylene (C2H4), ethane (C2H6) and ethanol (C2H5OH) products can be obtained on these three designed electrocatalysts with ultra-small limiting potentials (−0.20~−0.41 V) and low kinetic energy barriers of C-C coupling (0.52~0.91 eV). Meanwhile, the competitive one-carbon (C1) products and hydrogen evolution reaction can also be effectively suppressed. The promising activity and selectivity of these three designed electrocatalysts render them ideal candidates for CO electroreduction, thus providing a cost-effective opportunity to achieve a sustainable production of high value C2 chemicals and fuels.
2022, 33(4): 2188-2194
doi: 10.1016/j.cclet.2021.09.003
Abstract:
Nitrogen reduction reactions (NRR) under room conditions remain the challenge for N2 activation on metal-based catalysis materials. Herein, the M-doped CeO2(111) (M = Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) with oxygen vacancies, are systematically investigated by spin-polarized DFT + U calculations. We discuss briefly the situation of OVs on pure and reduced cerium, and we found that (1) doping TMs can promote the formation of oxygen defects, apart from Ti and V-dopant, (2) the O atoms are easier to escape connecting to M atoms than the ones of adjacent atoms connecting to the Ce(III), the value of OVs formation energies decrease as the TMs radius decrease. Also, our computational results show that Cr-doped, Mn-doped, Fe-doped, and Co-doped CeO2(111) adsorbs N2 strongly than the stoichiometric surface and other M-doped CeO2 surfaces with adsorption energies of −0.82, −1.02, −0.83 and −1.05 eV. Through COHP analysis, it is found that the predicted active sites have good catalytic performance.
Nitrogen reduction reactions (NRR) under room conditions remain the challenge for N2 activation on metal-based catalysis materials. Herein, the M-doped CeO2(111) (M = Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) with oxygen vacancies, are systematically investigated by spin-polarized DFT + U calculations. We discuss briefly the situation of OVs on pure and reduced cerium, and we found that (1) doping TMs can promote the formation of oxygen defects, apart from Ti and V-dopant, (2) the O atoms are easier to escape connecting to M atoms than the ones of adjacent atoms connecting to the Ce(III), the value of OVs formation energies decrease as the TMs radius decrease. Also, our computational results show that Cr-doped, Mn-doped, Fe-doped, and Co-doped CeO2(111) adsorbs N2 strongly than the stoichiometric surface and other M-doped CeO2 surfaces with adsorption energies of −0.82, −1.02, −0.83 and −1.05 eV. Through COHP analysis, it is found that the predicted active sites have good catalytic performance.
Achieving higher performances without an external curing agent in natural magnolol-based epoxy resin
2022, 33(4): 2195-2199
doi: 10.1016/j.cclet.2021.09.025
Abstract:
Bio-based epoxy thermoset prepared from renewable biomass raw materials can alleviate fossil energy crisis and reduce environmental pollution, which satisfies the needs of sustainable social development. In this study, a bio-based epoxy thermoset precursor (MGOL-EP) was synthesized from a naturally occurring magnolol through a facile and efficient one-step process. And the fully bio-based epoxy thermoset (MGOL-EP-SC) was obtained by self-curing without adding any other hardener. MGOL-EP-SC revealed an extremely high glass-transition temperature (Tg) of 265 ℃ and char yield of 53.2% (in N2), which were at the highest level among the fully bio-based epoxy thermosets reported so far. In addition, when the MGOL-EP was cured with 4, 4′-methylenedianiline (DDM), Tg of the MGOL-EP/DDM was decreased by 61 ℃ and the other comprehensive performance had also been decreased, which was due to a reduction in biphenyl structure content and cross-linking density by adding the external curing agents. Moreover, the MGOL-EP-SC presented certain killing rate (48.4%) to Staphylococcus aureus. These findings provide a new design strategy for engineering high-performance and functional epoxy thermoset with high biomass content.
Bio-based epoxy thermoset prepared from renewable biomass raw materials can alleviate fossil energy crisis and reduce environmental pollution, which satisfies the needs of sustainable social development. In this study, a bio-based epoxy thermoset precursor (MGOL-EP) was synthesized from a naturally occurring magnolol through a facile and efficient one-step process. And the fully bio-based epoxy thermoset (MGOL-EP-SC) was obtained by self-curing without adding any other hardener. MGOL-EP-SC revealed an extremely high glass-transition temperature (Tg) of 265 ℃ and char yield of 53.2% (in N2), which were at the highest level among the fully bio-based epoxy thermosets reported so far. In addition, when the MGOL-EP was cured with 4, 4′-methylenedianiline (DDM), Tg of the MGOL-EP/DDM was decreased by 61 ℃ and the other comprehensive performance had also been decreased, which was due to a reduction in biphenyl structure content and cross-linking density by adding the external curing agents. Moreover, the MGOL-EP-SC presented certain killing rate (48.4%) to Staphylococcus aureus. These findings provide a new design strategy for engineering high-performance and functional epoxy thermoset with high biomass content.
2022, 33(4): 2200-2204
doi: 10.1016/j.cclet.2021.09.052
Abstract:
Chloride ion batteries (CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in mesocellular carbon foam matrix by a new vacuum impregnation approach. The mesocellular carbon foam with large interconnected pores (15.7 or 23.2 nm) may buffer the large volume variation of bismuth chloride during charge and discharge, giving rise to significantly enhanced electrochemical performance. The as-prepared bismuth chloride@mesocellular carbon foam cathode delivered an initial discharge capacity of 298 mAh/g and a reversible capacity of 91 mAh/g after 60 cycles. In contrast, the pure bismuth chloride cathode almost cannot discharge after 30 cycles. This is the first report that the metal chloride cathode can achieve a prolonged cycling in CIBs.
Chloride ion batteries (CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in mesocellular carbon foam matrix by a new vacuum impregnation approach. The mesocellular carbon foam with large interconnected pores (15.7 or 23.2 nm) may buffer the large volume variation of bismuth chloride during charge and discharge, giving rise to significantly enhanced electrochemical performance. The as-prepared bismuth chloride@mesocellular carbon foam cathode delivered an initial discharge capacity of 298 mAh/g and a reversible capacity of 91 mAh/g after 60 cycles. In contrast, the pure bismuth chloride cathode almost cannot discharge after 30 cycles. This is the first report that the metal chloride cathode can achieve a prolonged cycling in CIBs.
2022, 33(4): 2205-2211
doi: 10.1016/j.cclet.2021.09.063
Abstract:
Conductive hydrogels have attracted considerable attention owing to their potential for use as electronic skin and sensors. However, the loss of the inherent elasticity or conductivity in cold environments severely limits their working conditions. Generally, organic solvents or inorganic salts can be incorporated into hydrogels as cryoprotectants. However, their toxicity and/or corrosive nature as well as the significant water loss during the solvent exchange present serious difficulties. Herein, a liquid-like yet non-toxic polymer-polyethylene glycol (PEG) was attempted as one of the components of solvent for hydrogels. In the premixed PEG-water hybrid solvent, polyacrylamide (PAAm) was in situ polymerized, overcoming the inevitable water loss induced by the high osmotic pressure of the PEG solution and achieving tailored water capacity. Interestingly, the mechanical strength ("soft-to-rigid" transition) and anti-freezing properties of organohydrogels can be simultaneously tuned over a very wide range through adjusting PEG content. This was due to that with increasing PEG in solvent, the PAAm chains transformed from stretching to curling conformation, while PEG bonded with water molecules via hydrogen bonds, weakening the crystallization of water at subzero temperature. Additionally, a highly conductive Ti3C2Tx-MXene was further introduced into the organohydrogels, achieving a uniform distribution triggered by the attractive interaction between the rich functional groups of the nanofillers and the polymer chains. The nanocomposite hydrogels demonstrate high electrical conductivity and strain sensitivity, along with a wide working temperature window. Such a material can be used for monitoring human joint movement even at low temperature and has potential applications in wearable strain sensors.
Conductive hydrogels have attracted considerable attention owing to their potential for use as electronic skin and sensors. However, the loss of the inherent elasticity or conductivity in cold environments severely limits their working conditions. Generally, organic solvents or inorganic salts can be incorporated into hydrogels as cryoprotectants. However, their toxicity and/or corrosive nature as well as the significant water loss during the solvent exchange present serious difficulties. Herein, a liquid-like yet non-toxic polymer-polyethylene glycol (PEG) was attempted as one of the components of solvent for hydrogels. In the premixed PEG-water hybrid solvent, polyacrylamide (PAAm) was in situ polymerized, overcoming the inevitable water loss induced by the high osmotic pressure of the PEG solution and achieving tailored water capacity. Interestingly, the mechanical strength ("soft-to-rigid" transition) and anti-freezing properties of organohydrogels can be simultaneously tuned over a very wide range through adjusting PEG content. This was due to that with increasing PEG in solvent, the PAAm chains transformed from stretching to curling conformation, while PEG bonded with water molecules via hydrogen bonds, weakening the crystallization of water at subzero temperature. Additionally, a highly conductive Ti3C2Tx-MXene was further introduced into the organohydrogels, achieving a uniform distribution triggered by the attractive interaction between the rich functional groups of the nanofillers and the polymer chains. The nanocomposite hydrogels demonstrate high electrical conductivity and strain sensitivity, along with a wide working temperature window. Such a material can be used for monitoring human joint movement even at low temperature and has potential applications in wearable strain sensors.
2022, 33(4): 2212-2212
doi: 10.1016/j.cclet.2022.01.035
Abstract:
