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2024 Volume 35 Issue 1
2024, 35(1): 108136
doi: 10.1016/j.cclet.2023.108136
Abstract:
The A2A adenosine receptor (A2AAR) has attracted attention as an emerging immunotherapeutic target with several antagonists being evaluated in clinical trials. However, A2AAR antagonists show limited efficacy as monotherapies. Herein, we communicate our design and synthesis of a novel series of A2AAR/histone deacetylase (HDAC) bifunctional inhibitors, based on the core structure of the A2AAR antagonist PBF-509. The new compounds were designed using a pharmacophore-merging strategy and features a tri-substituted pyrimidine core. The binding affinity for A2AAR and inhibitory activity against HDACs of all the new compounds were tested. A number of compounds exhibited nanomolar or subnanomolar activity against both targets and some showed equally potent antiproliferative activity against MC38, CT26 and HCT116 colon cancer lines compared to HDAC inhibitors SAHA and MGCD-0103 in vitro. The binding poses of compound 5a in both A2AAR and HDAC1 were predicted by molecular docking studies. Collectively, these results suggest these tri-substituted pyrimidine derivatives are promising leads for developing A2AAR/HDAC dual-acting compounds as novel antitumor agents.
The A2A adenosine receptor (A2AAR) has attracted attention as an emerging immunotherapeutic target with several antagonists being evaluated in clinical trials. However, A2AAR antagonists show limited efficacy as monotherapies. Herein, we communicate our design and synthesis of a novel series of A2AAR/histone deacetylase (HDAC) bifunctional inhibitors, based on the core structure of the A2AAR antagonist PBF-509. The new compounds were designed using a pharmacophore-merging strategy and features a tri-substituted pyrimidine core. The binding affinity for A2AAR and inhibitory activity against HDACs of all the new compounds were tested. A number of compounds exhibited nanomolar or subnanomolar activity against both targets and some showed equally potent antiproliferative activity against MC38, CT26 and HCT116 colon cancer lines compared to HDAC inhibitors SAHA and MGCD-0103 in vitro. The binding poses of compound 5a in both A2AAR and HDAC1 were predicted by molecular docking studies. Collectively, these results suggest these tri-substituted pyrimidine derivatives are promising leads for developing A2AAR/HDAC dual-acting compounds as novel antitumor agents.
2024, 35(1): 108193
doi: 10.1016/j.cclet.2023.108193
Abstract:
Talaroclauxins A and B (1 and 2), two novel duclauxin hybrids, were obtained from Talaromyces stipitatus, along with three new (3−5) and one known analogue (6). Their structures were determined by NMR spectroscopy, HRESIMS, single-crystal X-ray diffraction, and quantum chemical calculations. Compound 1 is the first example of duclauxin-ergosterol hybrid featuring an unprecedented dodecacyclic ring system formed via a [4 + 2] cycloaddition, while compound 2, bearing an unusual 6/6/6/5/6/6/6/6 ring system, is a new member of the rare duclauxin-polyketide hybrid class of natural products. Plausible biosynthetic pathways for 1−6 are proposed. Compound 5 displayed moderate neuroprotective effects in glutamate sodium-induced SH-SY5Y cells.
Talaroclauxins A and B (1 and 2), two novel duclauxin hybrids, were obtained from Talaromyces stipitatus, along with three new (3−5) and one known analogue (6). Their structures were determined by NMR spectroscopy, HRESIMS, single-crystal X-ray diffraction, and quantum chemical calculations. Compound 1 is the first example of duclauxin-ergosterol hybrid featuring an unprecedented dodecacyclic ring system formed via a [4 + 2] cycloaddition, while compound 2, bearing an unusual 6/6/6/5/6/6/6/6 ring system, is a new member of the rare duclauxin-polyketide hybrid class of natural products. Plausible biosynthetic pathways for 1−6 are proposed. Compound 5 displayed moderate neuroprotective effects in glutamate sodium-induced SH-SY5Y cells.
2024, 35(1): 108225
doi: 10.1016/j.cclet.2023.108225
Abstract:
The chemoselective hydrogenation of structurally diverse nitroaromatics is a challenging process. Generally, catalyst activity tends to decrease when excellent selectivity is guaranteed. We here present a novel photocatalyst combining amino-functionalized carbon dots (N-CDs) with copper selenite nanoparticles (N-CDs@CuSeO3) for simultaneously improving selectivity and activity. Under visible light irradiation, the prepared N-CDs@CuSeO3 exhibits 100% catalytic selectivity for the formation of 4-aminostyrene at full conversion of 4-nitrostyrene in aqueous solvent within a few minutes. Such excellent photocatalytic performance is mainly attributed to the precise control of the hydrogen species released from the ammonia borane by means of light-converted electrons upon N-CDs@CuSeO3. Besides, the defect states at the interface of N-CDs and CuSeO3 enable holes to be trapped for promoting separation and transfer of photogenerated charges, allowing more hydrogen species to participate in catalytic reaction.
The chemoselective hydrogenation of structurally diverse nitroaromatics is a challenging process. Generally, catalyst activity tends to decrease when excellent selectivity is guaranteed. We here present a novel photocatalyst combining amino-functionalized carbon dots (N-CDs) with copper selenite nanoparticles (N-CDs@CuSeO3) for simultaneously improving selectivity and activity. Under visible light irradiation, the prepared N-CDs@CuSeO3 exhibits 100% catalytic selectivity for the formation of 4-aminostyrene at full conversion of 4-nitrostyrene in aqueous solvent within a few minutes. Such excellent photocatalytic performance is mainly attributed to the precise control of the hydrogen species released from the ammonia borane by means of light-converted electrons upon N-CDs@CuSeO3. Besides, the defect states at the interface of N-CDs and CuSeO3 enable holes to be trapped for promoting separation and transfer of photogenerated charges, allowing more hydrogen species to participate in catalytic reaction.
2024, 35(1): 108277
doi: 10.1016/j.cclet.2023.108277
Abstract:
Carbon dots (CDs) have been attracted much attention and widely studied due to their excellent fluorescence (FL) properties, better biocompatibility and outstanding photo/chemical stability. However, the disadvantage of lower quantum yield (QY) still limits its wide application. Herein, we reported a novel and convenient strategy to prepare photo-induced Ag/CDs (p-Ag/CDs) by irradiating the mixed Ag+ and hydrophobic CDs (h-CDs) acetone solution with ultraviolet (UV) light. The obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift (460 nm) than h-CDs (520 nm). The QY of p-Ag/CDs is measured to be 51.1%, which is 10.4 times higher than that of h-CDs (4.9%), indicating that photo-induced Ag modulation can effectively improve the optical properties of CDs. The mechanisms for the FL enhancement and blue shift of h-CDs are studied in detail. The results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles (AgNPs) by UV light irradiation based on metal-enhanced fluorescence (MEF), and the increased oxygen-contained groups in this process lead to the blue shift in CDs fluorescence. Interestingly, the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions (S2−) detection than that of h-CDs, which have a lower response to S2−. This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields.
Carbon dots (CDs) have been attracted much attention and widely studied due to their excellent fluorescence (FL) properties, better biocompatibility and outstanding photo/chemical stability. However, the disadvantage of lower quantum yield (QY) still limits its wide application. Herein, we reported a novel and convenient strategy to prepare photo-induced Ag/CDs (p-Ag/CDs) by irradiating the mixed Ag+ and hydrophobic CDs (h-CDs) acetone solution with ultraviolet (UV) light. The obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift (460 nm) than h-CDs (520 nm). The QY of p-Ag/CDs is measured to be 51.1%, which is 10.4 times higher than that of h-CDs (4.9%), indicating that photo-induced Ag modulation can effectively improve the optical properties of CDs. The mechanisms for the FL enhancement and blue shift of h-CDs are studied in detail. The results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles (AgNPs) by UV light irradiation based on metal-enhanced fluorescence (MEF), and the increased oxygen-contained groups in this process lead to the blue shift in CDs fluorescence. Interestingly, the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions (S2−) detection than that of h-CDs, which have a lower response to S2−. This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields.
2024, 35(1): 108279
doi: 10.1016/j.cclet.2023.108279
Abstract:
Exciton behavior is crucial to the exploitation of light-emitting conjugated polymer (LCPs) for optoelectronic devices. Singlet excitons are easily trapped by the intrinsically defect structures. Herein, we set a polyfluorenol (PPFOH) as an example to systematically investigate its photophysical behavior to check the role of defect structures in LCPs. According to time-resolved photoluminescence analysis, the feature emission peaks from individual chain of PPFOH in diluted DMF solution is effectively avoided the influence of fluorenone formation, but the residual green-band emission at 550 nm is easily observed in the PL spectra of PPFOH dilute toluene solution obtained delay 1.5 ns, confirmed the formation of "guest" physical aggregation-induced defect structure. Remarkably, efficient and ultrafast energy transfer from individual chain to defect structure is observed in PPFOH films. Interestingly, the efficient energy transfer happened for the film obtained from DMF solution (200 ps) than those of toluene ones (600 ps). Meanwhile, compared to relatively stable green-band emission in PPFOH film from toluene solution, red-shifted emission peak (11 nm) of PPFOH film from DMF solutions exposed to saturated DNT vapor also confirmed their different aggregation-induced green-band emission. Therefore, this aggregation defect structures are influenced on the photophysical property of LCPs in solid states.
Exciton behavior is crucial to the exploitation of light-emitting conjugated polymer (LCPs) for optoelectronic devices. Singlet excitons are easily trapped by the intrinsically defect structures. Herein, we set a polyfluorenol (PPFOH) as an example to systematically investigate its photophysical behavior to check the role of defect structures in LCPs. According to time-resolved photoluminescence analysis, the feature emission peaks from individual chain of PPFOH in diluted DMF solution is effectively avoided the influence of fluorenone formation, but the residual green-band emission at 550 nm is easily observed in the PL spectra of PPFOH dilute toluene solution obtained delay 1.5 ns, confirmed the formation of "guest" physical aggregation-induced defect structure. Remarkably, efficient and ultrafast energy transfer from individual chain to defect structure is observed in PPFOH films. Interestingly, the efficient energy transfer happened for the film obtained from DMF solution (200 ps) than those of toluene ones (600 ps). Meanwhile, compared to relatively stable green-band emission in PPFOH film from toluene solution, red-shifted emission peak (11 nm) of PPFOH film from DMF solutions exposed to saturated DNT vapor also confirmed their different aggregation-induced green-band emission. Therefore, this aggregation defect structures are influenced on the photophysical property of LCPs in solid states.
2024, 35(1): 108287
doi: 10.1016/j.cclet.2023.108287
Abstract:
In this work, semirigid linkers of the alkyl-thiophene-alkyl structure are developed to construct double-cable polymers. Three alkyl units, propyl (C3H6), hexyl (C6H12), and dodecyl (C12H24), are applied as semirigid linkers, yielding three double-cable polymers: PBC6-T, PBC12-T, and PBC24-T, respectively. PBC12-T which uses C6H12-thiophene-C6H12 linkers is found to exhibit the best device efficiency of 5.56%, while PBC6-T and PBC24-T with shorter or longer linkers yield device efficiencies of only 2.65% and 1.09% in single-component organic solar cells (SCOSCs). Further studies reveal that PBC12-T exhibits higher crystallinity and improved charge transport, resulting in better efficiencies. Our work provides an approach to construct double-cable conjugated polymers with long alkyl linkers, and it shows the importance of the linker length for the photovoltaic performance of SCOSCs.
In this work, semirigid linkers of the alkyl-thiophene-alkyl structure are developed to construct double-cable polymers. Three alkyl units, propyl (C3H6), hexyl (C6H12), and dodecyl (C12H24), are applied as semirigid linkers, yielding three double-cable polymers: PBC6-T, PBC12-T, and PBC24-T, respectively. PBC12-T which uses C6H12-thiophene-C6H12 linkers is found to exhibit the best device efficiency of 5.56%, while PBC6-T and PBC24-T with shorter or longer linkers yield device efficiencies of only 2.65% and 1.09% in single-component organic solar cells (SCOSCs). Further studies reveal that PBC12-T exhibits higher crystallinity and improved charge transport, resulting in better efficiencies. Our work provides an approach to construct double-cable conjugated polymers with long alkyl linkers, and it shows the importance of the linker length for the photovoltaic performance of SCOSCs.
2024, 35(1): 108295
doi: 10.1016/j.cclet.2023.108295
Abstract:
The scope of stereochemistry recognition usually occurs near the chiral scaffold of a ligand or catalyst. Remote stereocontrol, which can surpass the limits of stereorecognition of remote prochiral centers, has long been a challenging object of great interest in asymmetric catalysis. The current work realized the remote stereocontrol of 1,7-zwitterion intermediates formed from Huang's o-amino aryl MBH carbonates. With simple and easily accessible β-ICD as the bifunctional catalyst, multifunctionalized tetrahydroquinoline derivatives could be synthesized via (4 + 2) cycloadditions with excellent enantioselectivity and diastereoselectivity under mild conditions. The strategy possesses broad substrate scope, and three types of electron-deficient enones are successfully applied. Mechanistic studies disclosed the Lewis base-catalyzed reaction pathway, and H-bonding between the catalyst and enones is crucial for long-range stereocontrol. Scale-up reaction and transformations of the tetrahydroquinoline products demonstrated the potential of this strategy.
The scope of stereochemistry recognition usually occurs near the chiral scaffold of a ligand or catalyst. Remote stereocontrol, which can surpass the limits of stereorecognition of remote prochiral centers, has long been a challenging object of great interest in asymmetric catalysis. The current work realized the remote stereocontrol of 1,7-zwitterion intermediates formed from Huang's o-amino aryl MBH carbonates. With simple and easily accessible β-ICD as the bifunctional catalyst, multifunctionalized tetrahydroquinoline derivatives could be synthesized via (4 + 2) cycloadditions with excellent enantioselectivity and diastereoselectivity under mild conditions. The strategy possesses broad substrate scope, and three types of electron-deficient enones are successfully applied. Mechanistic studies disclosed the Lewis base-catalyzed reaction pathway, and H-bonding between the catalyst and enones is crucial for long-range stereocontrol. Scale-up reaction and transformations of the tetrahydroquinoline products demonstrated the potential of this strategy.
2024, 35(1): 108303
doi: 10.1016/j.cclet.2023.108303
Abstract:
A method for the generation of alkyl radicals from inert alkyl C-O bonds has been developed via an iron/borane reagent/alkoxide catalytic system, which can be employed for the synthesis of amines from nitroarenes with excellent efficiency. Preliminary mechanistic studies reveal that the amine synthesis may be involving a single electron transfer pathway to form alkyl radicals, and the low-valent iron species may be the active intermediates.
A method for the generation of alkyl radicals from inert alkyl C-O bonds has been developed via an iron/borane reagent/alkoxide catalytic system, which can be employed for the synthesis of amines from nitroarenes with excellent efficiency. Preliminary mechanistic studies reveal that the amine synthesis may be involving a single electron transfer pathway to form alkyl radicals, and the low-valent iron species may be the active intermediates.
2024, 35(1): 108312
doi: 10.1016/j.cclet.2023.108312
Abstract:
Photodynamic therapy (PDT) is a clinically approved cancer treatment that uses energy of light to generate active substances that cause damage to the cancer. Photosensitizers are employed to absorb light and generate toxic reactive oxygen species (ROS) to damage biomolecules like DNA. At the same time, some chemotherapy drugs like nucleotide analogues can provide mechanism-guided promotion in the treatment efficacy of PDT. However, the photosensitizer and chemotherapy drugs used in PDT is usually organic molecules, which suffers from bad solubility, fast clearance, and acute toxicity. To achieve targeted treatment, a reasonable delivery system is necessary. Therefore, we reported a metal-phenolic network where IR780 and gemcitabine were coupled chemically to overcome these shortcomings. The enhanced PDT effects can be realized by the promoted cell death both in vitro and in vivo. Moreover, the synergistic therapy also induced T-cell mediated anti-tumor immune response, which was significant for the inhibition of distant tumor growth. This work expanded the biomedical application of metal-phenolic materials and contribute to the wider application of photodynamic cancer therapy.
Photodynamic therapy (PDT) is a clinically approved cancer treatment that uses energy of light to generate active substances that cause damage to the cancer. Photosensitizers are employed to absorb light and generate toxic reactive oxygen species (ROS) to damage biomolecules like DNA. At the same time, some chemotherapy drugs like nucleotide analogues can provide mechanism-guided promotion in the treatment efficacy of PDT. However, the photosensitizer and chemotherapy drugs used in PDT is usually organic molecules, which suffers from bad solubility, fast clearance, and acute toxicity. To achieve targeted treatment, a reasonable delivery system is necessary. Therefore, we reported a metal-phenolic network where IR780 and gemcitabine were coupled chemically to overcome these shortcomings. The enhanced PDT effects can be realized by the promoted cell death both in vitro and in vivo. Moreover, the synergistic therapy also induced T-cell mediated anti-tumor immune response, which was significant for the inhibition of distant tumor growth. This work expanded the biomedical application of metal-phenolic materials and contribute to the wider application of photodynamic cancer therapy.
2024, 35(1): 108320
doi: 10.1016/j.cclet.2023.108320
Abstract:
Metal-organic frameworks (MOFs) with inherent porosity and suspended acidic groups are promising proton conducting materials in water or aqua-ammonia media. Herein we report a new lanthanide phosphonate, namely, Dy2(amp2H2)2(mal)(H2O)2·5H2O (MDAF-6). It possesses a 3D open-framework structure, and shows a high NH3 adsorption capacity of 142.4 cm3/g at P/P0 = 0.98 at 298 K due to acid-base interaction. Interestingly, the proton conductivity of MDAF-6-NH3 is enhanced by five orders of magnitude compared to MDAF-6 after 8.5 h exposure in saturated NH3-H2O vapor, indicating the importance of coexistent conjugate acid-base pairs of H3O+-H2O and NH4+-NH3 in promoting proton conduction. Magnetic studies of MDAF-6 revealed slow magnetization relaxation under zero dc field, characteristic of single-molecule magnet behavior. This work provides not only a new multifunctional MOF material, but also a new strategy to improve proton conduction in aqua-ammonia medium.
Metal-organic frameworks (MOFs) with inherent porosity and suspended acidic groups are promising proton conducting materials in water or aqua-ammonia media. Herein we report a new lanthanide phosphonate, namely, Dy2(amp2H2)2(mal)(H2O)2·5H2O (MDAF-6). It possesses a 3D open-framework structure, and shows a high NH3 adsorption capacity of 142.4 cm3/g at P/P0 = 0.98 at 298 K due to acid-base interaction. Interestingly, the proton conductivity of MDAF-6-NH3 is enhanced by five orders of magnitude compared to MDAF-6 after 8.5 h exposure in saturated NH3-H2O vapor, indicating the importance of coexistent conjugate acid-base pairs of H3O+-H2O and NH4+-NH3 in promoting proton conduction. Magnetic studies of MDAF-6 revealed slow magnetization relaxation under zero dc field, characteristic of single-molecule magnet behavior. This work provides not only a new multifunctional MOF material, but also a new strategy to improve proton conduction in aqua-ammonia medium.
2024, 35(1): 108323
doi: 10.1016/j.cclet.2023.108323
Abstract:
Mitochondrial damage is closely related to the occurrence of many diseases. However, accurate monitoring and reporting of mitochondrial damage are not easy. Here, we developed a small molecule fluorescent probe named CB-Cl, which has splendid spectral properties (large Stokes shift, strong affinity for RNA, etc.) and excellent targeting ability to intracellular mitochondria. After mitochondria were damaged by external stimuli, CB-Cl would light up the nucleolus as a signal reporter. The cascade imaging of mitochondria and nucleolus using CB-Cl can monitor and visualize the mitochondrial status in living cells in real-time. Based on the above advantages, the probe CB-Cl has reference significance for the related research of mitochondrial damage and the prevention and treatment of related diseases.
Mitochondrial damage is closely related to the occurrence of many diseases. However, accurate monitoring and reporting of mitochondrial damage are not easy. Here, we developed a small molecule fluorescent probe named CB-Cl, which has splendid spectral properties (large Stokes shift, strong affinity for RNA, etc.) and excellent targeting ability to intracellular mitochondria. After mitochondria were damaged by external stimuli, CB-Cl would light up the nucleolus as a signal reporter. The cascade imaging of mitochondria and nucleolus using CB-Cl can monitor and visualize the mitochondrial status in living cells in real-time. Based on the above advantages, the probe CB-Cl has reference significance for the related research of mitochondrial damage and the prevention and treatment of related diseases.
2024, 35(1): 108325
doi: 10.1016/j.cclet.2023.108325
Abstract:
A dimesitylboryl-ended oligothiophene with tetrazine as core (BTz) was synthesized and its reactivity and spectral changes toward trans-cyclooctene ((4E)-TCO-OH), cis-cyclooctene and bicyclo[6.1.0]non-4-yn-9-ylmethanol were comprehensively studied. The fluorescence intensity of BTz was enhanced up to more than 100 times upon bioorthogonal reaction with (4E)-TCO-OH. In addition, the first crystal structure of isolated product of tetrazine derivative with cyclooctene was determined, which clearly confirmed a dehydrogenation occurred after Diels–Alder reaction under ambient conditions.
A dimesitylboryl-ended oligothiophene with tetrazine as core (BTz) was synthesized and its reactivity and spectral changes toward trans-cyclooctene ((4E)-TCO-OH), cis-cyclooctene and bicyclo[6.1.0]non-4-yn-9-ylmethanol were comprehensively studied. The fluorescence intensity of BTz was enhanced up to more than 100 times upon bioorthogonal reaction with (4E)-TCO-OH. In addition, the first crystal structure of isolated product of tetrazine derivative with cyclooctene was determined, which clearly confirmed a dehydrogenation occurred after Diels–Alder reaction under ambient conditions.
2024, 35(1): 108326
doi: 10.1016/j.cclet.2023.108326
Abstract:
Polycyclic aromatic hydrocarbons (PAHs) play an important role in the industry, and the development of new materials for the selective separation of PAHs is of great significance. In this work, we report a hexahedral metal-organic cage with low symmetry by subcomponent self-assembly. In this cage, the eight ZnⅡ centers adopt an interesting ΛΛ/ΔΔΔΔΔΔ or ΛΛΛΛΛΛ/ΔΔ configuration. This cage with a cavity volume of 520 Å3 can bind anthracene, phenanthrene, and pyrene to form 1:1 host-guest complexes, while the bigger triphenylene, chrysene, perylene, and coronene cannot be encapsulated. The binding constant Ka of pyrene is about 1.110 × 103 (mol/L)−1, which is more than an order of magnitude larger than that of anthracene and phenanthrene (111 (mol/L)−1, 277 (mol/L)−1, respectively). X-ray structure studies reveal that the pyrene is located in the cavity and stabilized by multiple CH⋅⋅⋅π interactions. After separation from a mixture of PAHs, pyrene with > 96.1% purity can be obtained. This work provides a useful method for the first time for the selective separation of pyrene from PAHs mixture by utilizing a metal-organic cage as the material, making it a useful tool for purifying and separating specific compounds from complex mixtures.
Polycyclic aromatic hydrocarbons (PAHs) play an important role in the industry, and the development of new materials for the selective separation of PAHs is of great significance. In this work, we report a hexahedral metal-organic cage with low symmetry by subcomponent self-assembly. In this cage, the eight ZnⅡ centers adopt an interesting ΛΛ/ΔΔΔΔΔΔ or ΛΛΛΛΛΛ/ΔΔ configuration. This cage with a cavity volume of 520 Å3 can bind anthracene, phenanthrene, and pyrene to form 1:1 host-guest complexes, while the bigger triphenylene, chrysene, perylene, and coronene cannot be encapsulated. The binding constant Ka of pyrene is about 1.110 × 103 (mol/L)−1, which is more than an order of magnitude larger than that of anthracene and phenanthrene (111 (mol/L)−1, 277 (mol/L)−1, respectively). X-ray structure studies reveal that the pyrene is located in the cavity and stabilized by multiple CH⋅⋅⋅π interactions. After separation from a mixture of PAHs, pyrene with > 96.1% purity can be obtained. This work provides a useful method for the first time for the selective separation of pyrene from PAHs mixture by utilizing a metal-organic cage as the material, making it a useful tool for purifying and separating specific compounds from complex mixtures.
2024, 35(1): 108330
doi: 10.1016/j.cclet.2023.108330
Abstract:
Graphite tailings produced by natural graphite is usually regarded as garbage to be buried underground, which would result in a certain waste of resources. Here, in order to explore the utilization of natural graphite tailings (NGT), a liquid-polyacrylonitrile (LPAN) is used to modify the NGT fragments and aggregate them together to form secondary graphite particles with low surface area and high tap density. Moreover, the modified NGT show much better electrochemical performances than those of original one. When tested in full cells coupled with NMC532 cathode, the material achieves a high rate capability and cycle stability at the cutoff voltage of 4.25 V as well as 4.45 V, which maintains 84.32% capacity retention after 500 cycles at 1 C rate (4.25 V), higher than that of the pristine one (73.65%). The enhanced performances can be attributed to the use of LPAN to create a unique carbon layer upon graphite tailings to reconstruct surface and repair defects, and also to granulate an isotropic structure of secondary graphite particles, which can help to weaken the anisotropy of Li+ diffusion pathway and form a uniform, complete and stable solid-electrolyte-interface (SEI) on the surface of primary NGT fragments to promote a fast Li+ diffusion and suppress lithium metal dendrites upon charge and discharge.
Graphite tailings produced by natural graphite is usually regarded as garbage to be buried underground, which would result in a certain waste of resources. Here, in order to explore the utilization of natural graphite tailings (NGT), a liquid-polyacrylonitrile (LPAN) is used to modify the NGT fragments and aggregate them together to form secondary graphite particles with low surface area and high tap density. Moreover, the modified NGT show much better electrochemical performances than those of original one. When tested in full cells coupled with NMC532 cathode, the material achieves a high rate capability and cycle stability at the cutoff voltage of 4.25 V as well as 4.45 V, which maintains 84.32% capacity retention after 500 cycles at 1 C rate (4.25 V), higher than that of the pristine one (73.65%). The enhanced performances can be attributed to the use of LPAN to create a unique carbon layer upon graphite tailings to reconstruct surface and repair defects, and also to granulate an isotropic structure of secondary graphite particles, which can help to weaken the anisotropy of Li+ diffusion pathway and form a uniform, complete and stable solid-electrolyte-interface (SEI) on the surface of primary NGT fragments to promote a fast Li+ diffusion and suppress lithium metal dendrites upon charge and discharge.
2024, 35(1): 108331
doi: 10.1016/j.cclet.2023.108331
Abstract:
Carbon aerogels prepared from renewable nano building blocks are rising-star materials and hold great promise in many fields. However, various defects formed during carbonization at high temperature disfavor the stress transfer and thus the fabrication of flexible carbon aerogel from renewable nano building blocks. Herein, a structural defect-reducing strategy is proposed by altering the pyrolysis route of cellulose nanofiber. Inorganic salt that inhibits the generation of tar volatilization during pyrolysis can prevent the formation of various structural defects. Microstructure with fewer defects can reduce stress concentration and remarkably enhance the compressibility of carbon aerogel, thus increasing the maximum stress retention of carbon aerogel. The carbon aerogel also has high stress sensor sensitivity and excellent temperature coefficient of resistance. The structural defect-reducing strategy will pave a new way to fabricate high-strength carbon materials for various fields.
Carbon aerogels prepared from renewable nano building blocks are rising-star materials and hold great promise in many fields. However, various defects formed during carbonization at high temperature disfavor the stress transfer and thus the fabrication of flexible carbon aerogel from renewable nano building blocks. Herein, a structural defect-reducing strategy is proposed by altering the pyrolysis route of cellulose nanofiber. Inorganic salt that inhibits the generation of tar volatilization during pyrolysis can prevent the formation of various structural defects. Microstructure with fewer defects can reduce stress concentration and remarkably enhance the compressibility of carbon aerogel, thus increasing the maximum stress retention of carbon aerogel. The carbon aerogel also has high stress sensor sensitivity and excellent temperature coefficient of resistance. The structural defect-reducing strategy will pave a new way to fabricate high-strength carbon materials for various fields.
2024, 35(1): 108333
doi: 10.1016/j.cclet.2023.108333
Abstract:
While nickel(Ⅱ) complexes have been widely used as catalysts for carbon-carbon coupling reactions, the exploration of their photophysical and photochemical properties is still in the infancy. Here, a series of square-planar Ni(Ⅱ) complexes [(diNHC)NiX2] bearing chelating benzimidazole-based bis(N-heterocyclic carbene) ligands and varying anionic coligands (1, X = Cl; 2, X = Br; 3, X = I) are synthesized and structurally characterized. In solid state, both 1 and 2 exhibit orange-red photoluminescence under ambient conditions. The photophysical and electrochemical measurements along with density functional theory (DFT) calculations reveal that the low-energy emissions can be attributed to singlet excited states with ligand-to-ligand charge-transfer (LLCT) character. This work suggests that strong-field N-heterocyclic carbene ligands play a crucial role to achieve the luminescence of Ni(Ⅱ) complexes.
While nickel(Ⅱ) complexes have been widely used as catalysts for carbon-carbon coupling reactions, the exploration of their photophysical and photochemical properties is still in the infancy. Here, a series of square-planar Ni(Ⅱ) complexes [(diNHC)NiX2] bearing chelating benzimidazole-based bis(N-heterocyclic carbene) ligands and varying anionic coligands (1, X = Cl; 2, X = Br; 3, X = I) are synthesized and structurally characterized. In solid state, both 1 and 2 exhibit orange-red photoluminescence under ambient conditions. The photophysical and electrochemical measurements along with density functional theory (DFT) calculations reveal that the low-energy emissions can be attributed to singlet excited states with ligand-to-ligand charge-transfer (LLCT) character. This work suggests that strong-field N-heterocyclic carbene ligands play a crucial role to achieve the luminescence of Ni(Ⅱ) complexes.
2024, 35(1): 108340
doi: 10.1016/j.cclet.2023.108340
Abstract:
We have synthesized two copper nanoclusters (NCs) with a protection of the same ligand diphenylphosphino-2-pyridine (C17H14NP, dppy for short), formulated as Cu4(dppy)4Cl2 and Cu21(dppy)10, respectively. The former one bears a distorted tetrahedron Cu4 core with its six edges fully protected by chlorine and dppy ligands, while the latter presents a symmetric Cu21 core on which ten dppy molecules function as monolayer protection via well-organized monodentate or bidentate coordination. Interestingly, the Cu4(dppy)4Cl2 cluster exhibits a strong yellow emission at ~577 nm, while Cu21(dppy)10 displays dual emissions in purple (~368 nm) and green (~516 nm) regions respectively. In combination with TD-DFT calculations, we demonstrate the origin of altered emissions and unique stability of the two copper nanoclusters pertaining to the ligand coordination and metallic superatomic states.
We have synthesized two copper nanoclusters (NCs) with a protection of the same ligand diphenylphosphino-2-pyridine (C17H14NP, dppy for short), formulated as Cu4(dppy)4Cl2 and Cu21(dppy)10, respectively. The former one bears a distorted tetrahedron Cu4 core with its six edges fully protected by chlorine and dppy ligands, while the latter presents a symmetric Cu21 core on which ten dppy molecules function as monolayer protection via well-organized monodentate or bidentate coordination. Interestingly, the Cu4(dppy)4Cl2 cluster exhibits a strong yellow emission at ~577 nm, while Cu21(dppy)10 displays dual emissions in purple (~368 nm) and green (~516 nm) regions respectively. In combination with TD-DFT calculations, we demonstrate the origin of altered emissions and unique stability of the two copper nanoclusters pertaining to the ligand coordination and metallic superatomic states.
2024, 35(1): 108343
doi: 10.1016/j.cclet.2023.108343
Abstract:
The irregular defects and residual tumor tissue after surgery are challenges for effective breast cancer treatment. Herein, a smart hydrogel with self-adaptable size and dual responsive cargos release was fabricated to treat breast cancer via accurate tumor elimination, on-demand adipose tissue regeneration and effective infection inhibition. The hydrogel consisted of thiol groups ended polyethylene glycol (SH-PEG-SH) and doxorubicin encapsulated mesoporous silica nanocarriers (DOX@MSNs) double crosslinked hyaluronic acid (HA) after loading of antibacterial peptides (AP) and adipose-derived stem cells (ADSCs). A pH-cleavable unsaturated amide bond was pre-introduced between MSNs and HA frame to perform the tumor-specific acidic environment dependent DOX@MSNs release, meanwhile an esterase degradable glyceryl dimethacrylate cap was grafted on MSNs, which contributed to the selective chemotherapy in tumor cells with over-expressed esterase. The bond cleavage between MSNs and HA would also cause the swelling of the hydrogel, which not only provide sufficient space for the growth of ADSCs, but allows the hydrogel to fully fill the irregular defects generated by surgery and residual tumor atrophy, resulting in the on-demand regeneration of adipose tissue. Moreover, the sustained release of AP could be simultaneously triggered along with the size change of hydrogel, which further avoided bacterial infection to promote tissue regeneration.
The irregular defects and residual tumor tissue after surgery are challenges for effective breast cancer treatment. Herein, a smart hydrogel with self-adaptable size and dual responsive cargos release was fabricated to treat breast cancer via accurate tumor elimination, on-demand adipose tissue regeneration and effective infection inhibition. The hydrogel consisted of thiol groups ended polyethylene glycol (SH-PEG-SH) and doxorubicin encapsulated mesoporous silica nanocarriers (DOX@MSNs) double crosslinked hyaluronic acid (HA) after loading of antibacterial peptides (AP) and adipose-derived stem cells (ADSCs). A pH-cleavable unsaturated amide bond was pre-introduced between MSNs and HA frame to perform the tumor-specific acidic environment dependent DOX@MSNs release, meanwhile an esterase degradable glyceryl dimethacrylate cap was grafted on MSNs, which contributed to the selective chemotherapy in tumor cells with over-expressed esterase. The bond cleavage between MSNs and HA would also cause the swelling of the hydrogel, which not only provide sufficient space for the growth of ADSCs, but allows the hydrogel to fully fill the irregular defects generated by surgery and residual tumor atrophy, resulting in the on-demand regeneration of adipose tissue. Moreover, the sustained release of AP could be simultaneously triggered along with the size change of hydrogel, which further avoided bacterial infection to promote tissue regeneration.
2024, 35(1): 108346
doi: 10.1016/j.cclet.2023.108346
Abstract:
Due to the limitations of conventional chemotherapy including side effects, poor prognosis, and drug resistance, there is an urgent need for the development of a novel multi-functional combined therapy strategy. Dopamine-modified oxaliplatin prodrug (OXA-DA) was successfully synthesized in this study to ameliorate the organ distribution of oxaliplatin for improving the drug efficacy and reducing toxic side effects, and OXA-DA was applied to develop a porous oxaliplatin cross-linked polydopamine nanoparticle for loading siPD-L1 to construct multifunctional nanoplatform. The multifunctional nanoplatform was modified with poly(2-ethyl-2-oxazoline) (PEOz), which occurred charge reversal in the tumor microenvironment, and exerted the lysosomal escape effect in tumor cells to improve the bioavailability of small interfering RNA targeting programmed cell death-ligand 1 (siPD-L1). The pH-responsive charge reversal, photothermal, biodegradation, lysosomal escape ability, PD-L1 protein degradation, toxicity properties and multiple antitumor effects were comprehensively evaluated in vitro and in vivo experiments. The findings indicated that OXA-DA-siPD-L1@PDA-PEOz excellently induced tumor cell necrosis and apoptosis as a result of the synergistic effect of chemo-photothermal therapy, and upregulated CD8+ T cells produced interferon-γ (IFN-γ) to further attack the tumor cells. In conclusion, the novel nanoplatform-mediated chemo/photothermal/immunotherapy has promising clinical applications in the treatment of malignant tumors.
Due to the limitations of conventional chemotherapy including side effects, poor prognosis, and drug resistance, there is an urgent need for the development of a novel multi-functional combined therapy strategy. Dopamine-modified oxaliplatin prodrug (OXA-DA) was successfully synthesized in this study to ameliorate the organ distribution of oxaliplatin for improving the drug efficacy and reducing toxic side effects, and OXA-DA was applied to develop a porous oxaliplatin cross-linked polydopamine nanoparticle for loading siPD-L1 to construct multifunctional nanoplatform. The multifunctional nanoplatform was modified with poly(2-ethyl-2-oxazoline) (PEOz), which occurred charge reversal in the tumor microenvironment, and exerted the lysosomal escape effect in tumor cells to improve the bioavailability of small interfering RNA targeting programmed cell death-ligand 1 (siPD-L1). The pH-responsive charge reversal, photothermal, biodegradation, lysosomal escape ability, PD-L1 protein degradation, toxicity properties and multiple antitumor effects were comprehensively evaluated in vitro and in vivo experiments. The findings indicated that OXA-DA-siPD-L1@PDA-PEOz excellently induced tumor cell necrosis and apoptosis as a result of the synergistic effect of chemo-photothermal therapy, and upregulated CD8+ T cells produced interferon-γ (IFN-γ) to further attack the tumor cells. In conclusion, the novel nanoplatform-mediated chemo/photothermal/immunotherapy has promising clinical applications in the treatment of malignant tumors.
2024, 35(1): 108348
doi: 10.1016/j.cclet.2023.108348
Abstract:
White light emitting systems of pure organic materials have attracted extensive research interest due to their better compatibility and functional scalability. The reported organic white light materials are mainly based on the multi-channel emission regulation of the compound itself or the mixing of multicolor luminescence materials, but studies on the dependence between multicolor luminescence and the external environment are lacking, which limits the application of these materials in areas such as identification and sensing. This paper reports that the 4- or 3‑hydroxyl-substituted naphthalimides NapH1 and NapH2 form intermolecular hydrogen bonds with adjacent molecules in the environment, and undergo excited-state intermolecular proton transfer under irradiation, resulting in blue-yellow or blue-red dual fluorescence emission, respectively. Since the two compounds have different two-color luminescence channels and the two-color intensity ratio is affected by the environment, and the intermolecular hydrogen bond is determined by the hydrogen bond receptor, polarity, and temperature in the environment, the full spectrum from blue to red light and white light emission can be obtained by adjusting the mixing ratio of the two dyes and the solvent polarity and the ambient temperature. This environmentally sensitive white emission is used to detect the alkalinity of different papers, and the dyed paper can be used as a test strip for acid-base vapor detection.
White light emitting systems of pure organic materials have attracted extensive research interest due to their better compatibility and functional scalability. The reported organic white light materials are mainly based on the multi-channel emission regulation of the compound itself or the mixing of multicolor luminescence materials, but studies on the dependence between multicolor luminescence and the external environment are lacking, which limits the application of these materials in areas such as identification and sensing. This paper reports that the 4- or 3‑hydroxyl-substituted naphthalimides NapH1 and NapH2 form intermolecular hydrogen bonds with adjacent molecules in the environment, and undergo excited-state intermolecular proton transfer under irradiation, resulting in blue-yellow or blue-red dual fluorescence emission, respectively. Since the two compounds have different two-color luminescence channels and the two-color intensity ratio is affected by the environment, and the intermolecular hydrogen bond is determined by the hydrogen bond receptor, polarity, and temperature in the environment, the full spectrum from blue to red light and white light emission can be obtained by adjusting the mixing ratio of the two dyes and the solvent polarity and the ambient temperature. This environmentally sensitive white emission is used to detect the alkalinity of different papers, and the dyed paper can be used as a test strip for acid-base vapor detection.
2024, 35(1): 108352
doi: 10.1016/j.cclet.2023.108352
Abstract:
Lithium (Li)–CO2 battery is rising as an attractive energy-storage system with the competence of CO2 conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herein, a rational design on a highly catalytic Li–CO2 battery electrode built by graphdiyne powder as a multi-functional laminar scaffold with anchored highly dispersed Ru nanoparticles is explored. The strong interaction between the abundant acetylenic bond sites of graphdiyne scaffold and Ru nanoparticles can effectively promote the electrochemical progress and reduce the voltage polarization. The unique channels architecture of the cathodic catalyst with enough space not only accelerates CO2 diffusion and electrons/Li+ transport, but also allows a large amount of accommodation for discharged product (Li2CO3) to assure an advanced capacity. The corresponding Li–CO2 battery displays an advanced discharged capacity of 15,030 mAh/g at 500 mA/g, great capacity retention of 8873 mAh/g at 2 A/g, high coulombic efficiency of 97.6% at 500 mA/g and superior life span for 120 cycles with voltage gap of 1.67 V under a restricted capacity of 1000 mAh/g at 500 mA/g. Ex/in-situ studies prove that synergy between Ru nanoparticles and acetylene bonds of GDY can boost the round-trip CO2RR and CO2ER kinetics.
Lithium (Li)–CO2 battery is rising as an attractive energy-storage system with the competence of CO2 conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herein, a rational design on a highly catalytic Li–CO2 battery electrode built by graphdiyne powder as a multi-functional laminar scaffold with anchored highly dispersed Ru nanoparticles is explored. The strong interaction between the abundant acetylenic bond sites of graphdiyne scaffold and Ru nanoparticles can effectively promote the electrochemical progress and reduce the voltage polarization. The unique channels architecture of the cathodic catalyst with enough space not only accelerates CO2 diffusion and electrons/Li+ transport, but also allows a large amount of accommodation for discharged product (Li2CO3) to assure an advanced capacity. The corresponding Li–CO2 battery displays an advanced discharged capacity of 15,030 mAh/g at 500 mA/g, great capacity retention of 8873 mAh/g at 2 A/g, high coulombic efficiency of 97.6% at 500 mA/g and superior life span for 120 cycles with voltage gap of 1.67 V under a restricted capacity of 1000 mAh/g at 500 mA/g. Ex/in-situ studies prove that synergy between Ru nanoparticles and acetylene bonds of GDY can boost the round-trip CO2RR and CO2ER kinetics.
2024, 35(1): 108361
doi: 10.1016/j.cclet.2023.108361
Abstract:
Inflammatory bowel disease (IBD) is a refractory chronic intestinal inflammatory disease caused by a malfunction of immune system. As the key immune cells in the intestine, macrophages play an important role in maintaining intestinal homeostasis and tissue repair of the IBD. Pharmacological modulation of macrophage function exhibits the promising therapeutic effect for IBD. In this study, mannose-modified liposomes (MAN-LPs) are prepared for macrophage targeting to improve therapeutic efficiency. Rosiglitazone (ROSI) as an agonist of peroxisome proliferators-activated receptor γ (PPAR-γ) is used as the model drug to fabricate different sized liposomes. The impacts of mannose modification and particle size for macrophage targeting are investigated in cells, zebrafish, and mouse models and the therapeutic effects of the MAN-LPs are evaluated on dextran sulfate sodium (DSS)-induced IBD mouse. Compared to unmodified liposome, MAN-LPs display higher uptake by RAW 264.7 cells and better co-localization with macrophage in zebrafish model. Furthermore, MAN-LPs could effectively accumulate in the inflammatory intestinal sites in IBD mouse model. Most importantly, the targeting ability of MAN-LPs is obviously enhanced with the increasing of particle size, whereas the largest MAN-LPs particles achieve the best anti-inflammatory effect in cells, and a higher therapeutic efficiency in IBD mouse model. Therefore, mannose-modified liposome is a promising strategy for macrophage-targeting in IBD treatment. Particle size of MAN-LPs will affect macrophage targeting ability, as well as the therapeutic effect in-vivo.
Inflammatory bowel disease (IBD) is a refractory chronic intestinal inflammatory disease caused by a malfunction of immune system. As the key immune cells in the intestine, macrophages play an important role in maintaining intestinal homeostasis and tissue repair of the IBD. Pharmacological modulation of macrophage function exhibits the promising therapeutic effect for IBD. In this study, mannose-modified liposomes (MAN-LPs) are prepared for macrophage targeting to improve therapeutic efficiency. Rosiglitazone (ROSI) as an agonist of peroxisome proliferators-activated receptor γ (PPAR-γ) is used as the model drug to fabricate different sized liposomes. The impacts of mannose modification and particle size for macrophage targeting are investigated in cells, zebrafish, and mouse models and the therapeutic effects of the MAN-LPs are evaluated on dextran sulfate sodium (DSS)-induced IBD mouse. Compared to unmodified liposome, MAN-LPs display higher uptake by RAW 264.7 cells and better co-localization with macrophage in zebrafish model. Furthermore, MAN-LPs could effectively accumulate in the inflammatory intestinal sites in IBD mouse model. Most importantly, the targeting ability of MAN-LPs is obviously enhanced with the increasing of particle size, whereas the largest MAN-LPs particles achieve the best anti-inflammatory effect in cells, and a higher therapeutic efficiency in IBD mouse model. Therefore, mannose-modified liposome is a promising strategy for macrophage-targeting in IBD treatment. Particle size of MAN-LPs will affect macrophage targeting ability, as well as the therapeutic effect in-vivo.
2024, 35(1): 108382
doi: 10.1016/j.cclet.2023.108382
Abstract:
As a new concept having emerged in last few years, the "deep eutectic solvents" (DESs) effect integrated into the imprinting technology inevitably exposes design limitations of stimuli-responsive molecularly imprinted polymers (MIPs), as well as inadequate analysis of the adsorption performance of MIPs. Herein, a simple yet defined N-isopropylacrylamide/(3-acrylamidopropyl) trimethylammonium chloride (NIPAM/APTMAC) binary DESs system was proposed to prepare intelligent MIPs with thermo-sensitivity. Accordingly, magnetic and thermo-responsive MIPs based on functional monomers-derived DESs (TM-DESs-MIPs1) were synthesized, revealing DESs effect-regulated affinity/kinetics for the enhanced adsorption capability, eco-friendly thermo-regulated elution for high release efficiency, and simple magnetic separation, along with superior selectivity to rhein (RH) and good regeneration ability. TM-DESs-MIPs1 were utilized to extract RH from Cassiae semen samples coupled with high performance liquid chromatography (HPLC), yielding satisfactory recoveries (79.47%−110.82%) and low limits of detection (LOD) (16.67 µg/L). Another two kinds of MIPs adopting the thermo-responsive moiety-derived DESs effect strategy further demonstrated great applicability of such intelligent MIPs for analyses of complicated samples.
As a new concept having emerged in last few years, the "deep eutectic solvents" (DESs) effect integrated into the imprinting technology inevitably exposes design limitations of stimuli-responsive molecularly imprinted polymers (MIPs), as well as inadequate analysis of the adsorption performance of MIPs. Herein, a simple yet defined N-isopropylacrylamide/(3-acrylamidopropyl) trimethylammonium chloride (NIPAM/APTMAC) binary DESs system was proposed to prepare intelligent MIPs with thermo-sensitivity. Accordingly, magnetic and thermo-responsive MIPs based on functional monomers-derived DESs (TM-DESs-MIPs1) were synthesized, revealing DESs effect-regulated affinity/kinetics for the enhanced adsorption capability, eco-friendly thermo-regulated elution for high release efficiency, and simple magnetic separation, along with superior selectivity to rhein (RH) and good regeneration ability. TM-DESs-MIPs1 were utilized to extract RH from Cassiae semen samples coupled with high performance liquid chromatography (HPLC), yielding satisfactory recoveries (79.47%−110.82%) and low limits of detection (LOD) (16.67 µg/L). Another two kinds of MIPs adopting the thermo-responsive moiety-derived DESs effect strategy further demonstrated great applicability of such intelligent MIPs for analyses of complicated samples.
2024, 35(1): 108404
doi: 10.1016/j.cclet.2023.108404
Abstract:
Folding of molecules is an essential process in nature, and various molecular machines achieve their chemical and mechanical function via controlled folding of molecular conformations. The electric field offers a unique strategy to drive the folding of molecular conformation and to control charge transport through single molecules but remains unexplored. The single-molecule break junction technique provides access to detect the conformational changes via the monitoring of single-molecule conductance, and the electric field between two metal electrodes with nanoscale spacing can provide an extremely strong to achieve in-situ control and detection of molecular folding at the single-molecule level. Here, we use the electric field to control the single-molecule folding using the scanning tunneling microscope break junction (STM-BJ) technique. The electric fields induced folding could lead to a ~1400% conductance change of the single-molecule junctions, and the folding/unfolding process can be in-situ switched at the scale of milliseconds. DFT calculations suggest the conformational control originates from the electric field-induced charge injection, and the formation of homoconjugated conformation with the overlapped orbitals. This work provides the first demonstration of electric field-driven molecular folding, which is essential for the understanding of molecular machines in nature and for the design of artificial molecular machines.
Folding of molecules is an essential process in nature, and various molecular machines achieve their chemical and mechanical function via controlled folding of molecular conformations. The electric field offers a unique strategy to drive the folding of molecular conformation and to control charge transport through single molecules but remains unexplored. The single-molecule break junction technique provides access to detect the conformational changes via the monitoring of single-molecule conductance, and the electric field between two metal electrodes with nanoscale spacing can provide an extremely strong to achieve in-situ control and detection of molecular folding at the single-molecule level. Here, we use the electric field to control the single-molecule folding using the scanning tunneling microscope break junction (STM-BJ) technique. The electric fields induced folding could lead to a ~1400% conductance change of the single-molecule junctions, and the folding/unfolding process can be in-situ switched at the scale of milliseconds. DFT calculations suggest the conformational control originates from the electric field-induced charge injection, and the formation of homoconjugated conformation with the overlapped orbitals. This work provides the first demonstration of electric field-driven molecular folding, which is essential for the understanding of molecular machines in nature and for the design of artificial molecular machines.
2024, 35(1): 108409
doi: 10.1016/j.cclet.2023.108409
Abstract:
While enol-keto tautomerism has attracted great interest in Schiff bases and related compounds in solution and crystal states, the self-assembly of energy-unfavored keto form were scarcely investigated. Here, we report a keto-form directed self-assembly of a naphthalene-attached enantiomeric N-salicylideneanil analog L/DGG-Nap accompanied with a significantly amplified circularly polarized luminescence (CPL). It was found that LGG-Nap exists as a mixture of enol and keto form in monomer at a diluted toluene solution. The increment of the concentrations leads to the formation of predominated keto form, which subsequently triggers the self-assembly. Cryo-transmission electron microscopy (Cryo-TEM) revealed that a hierarchical assembly process happened upon increasing the concentration of LGG-Nap in toluene. Individual nanofibers formed at 1 × 10−4 mol/L and transferred into helical nanofiber bundles in 5 × 10−3 mol/L. Interestingly, while these is nearly no circular dichroism (CD) or CPL in the monomeric solution, the assembly showed strong CD and CPL. Remarkably, the dissymmetry factor (glum) was significantly amplified from zero in solution through the 0.005 in individual nanofiber to 0.1 in nanofiber bundles. This work demonstrates that the enol-keto tautomerism can be broken and trigger the self-assembly upon increasing the concentration, which can subsequently direct the chiral self-assembly and significantly amplify the dissymmetry factor of assembled CPL materials.
While enol-keto tautomerism has attracted great interest in Schiff bases and related compounds in solution and crystal states, the self-assembly of energy-unfavored keto form were scarcely investigated. Here, we report a keto-form directed self-assembly of a naphthalene-attached enantiomeric N-salicylideneanil analog L/DGG-Nap accompanied with a significantly amplified circularly polarized luminescence (CPL). It was found that LGG-Nap exists as a mixture of enol and keto form in monomer at a diluted toluene solution. The increment of the concentrations leads to the formation of predominated keto form, which subsequently triggers the self-assembly. Cryo-transmission electron microscopy (Cryo-TEM) revealed that a hierarchical assembly process happened upon increasing the concentration of LGG-Nap in toluene. Individual nanofibers formed at 1 × 10−4 mol/L and transferred into helical nanofiber bundles in 5 × 10−3 mol/L. Interestingly, while these is nearly no circular dichroism (CD) or CPL in the monomeric solution, the assembly showed strong CD and CPL. Remarkably, the dissymmetry factor (glum) was significantly amplified from zero in solution through the 0.005 in individual nanofiber to 0.1 in nanofiber bundles. This work demonstrates that the enol-keto tautomerism can be broken and trigger the self-assembly upon increasing the concentration, which can subsequently direct the chiral self-assembly and significantly amplify the dissymmetry factor of assembled CPL materials.
2024, 35(1): 108420
doi: 10.1016/j.cclet.2023.108420
Abstract:
Carbon dots (CDs) with superior fluorescence properties have attracted a growing number of research interests in anti-counterfeiting. However, the preparation of CDs with thermally turn-on fluorescence and full-color-emitting in visible spectrum is still a big challenge due to the complicated reaction mechanism in the formation of CDs. Here, a simple precursor-oriented strategy for the preparation of multicolor CDs with heat-stimuli turn-on fluorescence is reported. Comprehensive experimental characterizations and theoretical calculations revealed that the emission wavelength of CDs can be readily tuned from 460 nm to 654 nm with selected precursors, which was ascribed to the extent of conjugated sp2-domains (core states) and the amount of oxygen- and nitrogen-containing groups bound to sp2-domains (surface states). After simply mixing two or three kinds of CDs, a full-color range of fluorescence emission was realized, and the CDs-based fluorescence inks were successfully fabricated. Particularly, all the printed patterns from the inkjet exhibited a thermal-induced enhancement in fluorescence. On this basis, combining CDs with heating-induced "turn-off" fluorescence materials can lead to multidimensional and multistage encryption. These results demonstrate that the thermochromic and photochromic CDs with much more enhanced security exhibit promising application in data storage and encryption.
Carbon dots (CDs) with superior fluorescence properties have attracted a growing number of research interests in anti-counterfeiting. However, the preparation of CDs with thermally turn-on fluorescence and full-color-emitting in visible spectrum is still a big challenge due to the complicated reaction mechanism in the formation of CDs. Here, a simple precursor-oriented strategy for the preparation of multicolor CDs with heat-stimuli turn-on fluorescence is reported. Comprehensive experimental characterizations and theoretical calculations revealed that the emission wavelength of CDs can be readily tuned from 460 nm to 654 nm with selected precursors, which was ascribed to the extent of conjugated sp2-domains (core states) and the amount of oxygen- and nitrogen-containing groups bound to sp2-domains (surface states). After simply mixing two or three kinds of CDs, a full-color range of fluorescence emission was realized, and the CDs-based fluorescence inks were successfully fabricated. Particularly, all the printed patterns from the inkjet exhibited a thermal-induced enhancement in fluorescence. On this basis, combining CDs with heating-induced "turn-off" fluorescence materials can lead to multidimensional and multistage encryption. These results demonstrate that the thermochromic and photochromic CDs with much more enhanced security exhibit promising application in data storage and encryption.
2024, 35(1): 108421
doi: 10.1016/j.cclet.2023.108421
Abstract:
Aqueous zinc-ion batteries (AZIBs) have become a hotspot for electrochemical energy storage owing to the high safety, low cost, environmental friendliness, and favorable rate performance. However, the serious dissolution of cathode materials in aqueous electrolytes would lead to poor cyclability, which should be addressed before commercialization. Herein, we designed a Ti-doped V2O5 with yolk-shell microspherical structure for AZIBs. The Ti doping stabilizes the crystal structure and relieves the dissolution of V2O5 in aqueous ZnSO4 electrolyte. The optimized sample, Ti0.2V1.8O4.9, delivers a high capacity (355 mAh/g at 0.05 A/g) as well as good capacity retention (89% after 2500 cycles at 1.0 A/g). This work provides an effective strategy to mitigate the dissolution of cathode material in aqueous ZnSO4 electrolyte for cyclability enhancement.
Aqueous zinc-ion batteries (AZIBs) have become a hotspot for electrochemical energy storage owing to the high safety, low cost, environmental friendliness, and favorable rate performance. However, the serious dissolution of cathode materials in aqueous electrolytes would lead to poor cyclability, which should be addressed before commercialization. Herein, we designed a Ti-doped V2O5 with yolk-shell microspherical structure for AZIBs. The Ti doping stabilizes the crystal structure and relieves the dissolution of V2O5 in aqueous ZnSO4 electrolyte. The optimized sample, Ti0.2V1.8O4.9, delivers a high capacity (355 mAh/g at 0.05 A/g) as well as good capacity retention (89% after 2500 cycles at 1.0 A/g). This work provides an effective strategy to mitigate the dissolution of cathode material in aqueous ZnSO4 electrolyte for cyclability enhancement.
2024, 35(1): 108422
doi: 10.1016/j.cclet.2023.108422
Abstract:
Development of new metal-free heterogeneous catalysts has long been the focus of intense research interest. The integration of multifunctional monomers into the skeletons of porous organic polymers (POPs) provides an efficient pathway to achieve this goal. Herein, we rationally designed and successfully prepared a new Tröger's base (TB)-derived POPs by insertion of pillar[5]arene macrocycle as a positively auxiliary group. Combined the both merits of pillar[5]arene macrocycle and TB moiety, the as-prepared polymer was further explored as an effective metal-free heterogeneous catalyst and exhibited promoted catalytic performance in Knoevenagel condensation and CO2 conversion. This work provides a new strategy to fabricate metal-free heterogeneous catalysts based on macrocyclic POPs.
Development of new metal-free heterogeneous catalysts has long been the focus of intense research interest. The integration of multifunctional monomers into the skeletons of porous organic polymers (POPs) provides an efficient pathway to achieve this goal. Herein, we rationally designed and successfully prepared a new Tröger's base (TB)-derived POPs by insertion of pillar[5]arene macrocycle as a positively auxiliary group. Combined the both merits of pillar[5]arene macrocycle and TB moiety, the as-prepared polymer was further explored as an effective metal-free heterogeneous catalyst and exhibited promoted catalytic performance in Knoevenagel condensation and CO2 conversion. This work provides a new strategy to fabricate metal-free heterogeneous catalysts based on macrocyclic POPs.
2024, 35(1): 108442
doi: 10.1016/j.cclet.2023.108442
Abstract:
Polystyrene resins (PS) have been practical ion exchangers for radionuclides removal from water. However, nonspecific effects of ion exchange groups continue to be a major obstacle for emergency treatment with coexisting ions of high concentrations. The selectivity for Cs+ enables zirconium phosphate (ZrP) to be the most promising inorganic sorbent for radioactive cesium extraction, despite being difficult to synthesize and causing excessive pressure loss in fixed-bed reactors due to fine powder. Herein, through facile confined crystallization in host macropores, we prepared PS confined α-ZrP nanocrystalline (ZrP-PS). Size-screen sorption of layered α-ZrP and sulfonic acid group preconcentration of PS synergistically enable a considerably higher Cs+ affinity of ZrP-PS than PS, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis. ZrP-PS demonstrated remarkable cesium sequestration performance in both batch and continuous experiments, with a high adsorption capacity of 269.58 mg/g, a rapid equilibrium within 80 min, and a continuous effluent volume of 2300 L/kg sorbents. Given the excellent selectivity for Cs+ and flexibility to separate from treated water, ZrP-PS holds great promise as purification packages for the emergency treatment of radioactively contaminated water.
Polystyrene resins (PS) have been practical ion exchangers for radionuclides removal from water. However, nonspecific effects of ion exchange groups continue to be a major obstacle for emergency treatment with coexisting ions of high concentrations. The selectivity for Cs+ enables zirconium phosphate (ZrP) to be the most promising inorganic sorbent for radioactive cesium extraction, despite being difficult to synthesize and causing excessive pressure loss in fixed-bed reactors due to fine powder. Herein, through facile confined crystallization in host macropores, we prepared PS confined α-ZrP nanocrystalline (ZrP-PS). Size-screen sorption of layered α-ZrP and sulfonic acid group preconcentration of PS synergistically enable a considerably higher Cs+ affinity of ZrP-PS than PS, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis. ZrP-PS demonstrated remarkable cesium sequestration performance in both batch and continuous experiments, with a high adsorption capacity of 269.58 mg/g, a rapid equilibrium within 80 min, and a continuous effluent volume of 2300 L/kg sorbents. Given the excellent selectivity for Cs+ and flexibility to separate from treated water, ZrP-PS holds great promise as purification packages for the emergency treatment of radioactively contaminated water.
2024, 35(1): 108444
doi: 10.1016/j.cclet.2023.108444
Abstract:
In this study, magnesium and coconut shell carbon (CSC) were prepared by a ball milled process and used for water disinfection with adsorbing tiny amounts of copper(Ⅱ). Dissolved oxygen (DO) was reduced to hydrogen peroxide (H2O2) via a two-electron pathway by Mg corrosion. Cu(Ⅱ) in the wastewater will be enriched on the CSC surface and efficiently catalyzes H2O2 for inactivating E. coli. The results show that E. coli with an initial concentration of approximately 106 CFU/mL was under the detection limit (< 4 CFU/mL) within 15 min. All of the Cu(Ⅱ) could be adsorbed by the composite and catalyzed H2O2 to different active species. The quenching experiments, electron spin resonance (ESR) capture measurements and the UV-vis spectroscopy detection confirmed the present of the hydroxyl radicals (•OH), superoxide radicals (•O2−) and Cu(Ⅲ). Different with tradition Fenton like process, Cu(Ⅲ), rather than radicals, played the major role during the Mg-CSC/Cu(Ⅱ) process. In addition to the cellular membrane damage, most of the bacterial genomic DNA was also be degraded and the bacterial reactivation was avoided. The Mg-CSC/Cu(Ⅱ) process also showed a satisfied disinfection performance in real wastewater treatment. Overall, this study provides a new strategy for water disinfection.
In this study, magnesium and coconut shell carbon (CSC) were prepared by a ball milled process and used for water disinfection with adsorbing tiny amounts of copper(Ⅱ). Dissolved oxygen (DO) was reduced to hydrogen peroxide (H2O2) via a two-electron pathway by Mg corrosion. Cu(Ⅱ) in the wastewater will be enriched on the CSC surface and efficiently catalyzes H2O2 for inactivating E. coli. The results show that E. coli with an initial concentration of approximately 106 CFU/mL was under the detection limit (< 4 CFU/mL) within 15 min. All of the Cu(Ⅱ) could be adsorbed by the composite and catalyzed H2O2 to different active species. The quenching experiments, electron spin resonance (ESR) capture measurements and the UV-vis spectroscopy detection confirmed the present of the hydroxyl radicals (•OH), superoxide radicals (•O2−) and Cu(Ⅲ). Different with tradition Fenton like process, Cu(Ⅲ), rather than radicals, played the major role during the Mg-CSC/Cu(Ⅱ) process. In addition to the cellular membrane damage, most of the bacterial genomic DNA was also be degraded and the bacterial reactivation was avoided. The Mg-CSC/Cu(Ⅱ) process also showed a satisfied disinfection performance in real wastewater treatment. Overall, this study provides a new strategy for water disinfection.
2024, 35(1): 108449
doi: 10.1016/j.cclet.2023.108449
Abstract:
Aqueous rechargeable ammonium-ion batteries (AIBs) have drew considerable attention because of their capacity for high rates, low cost, and high safety. However, developing desired electrodes requiring stable structure in the aqueous fast ammoniation/de-ammoniation becomes urgent. Herein, an ammonium ion full battery using Cu3[Fe(CN)6]2 (CuHCF) acting to be a cathode and barium vanadate (BVO) acting to be an anode is described. Its excellent electrochemical behavior of Prussian blue analogs and the perfectly matched lattice structure of NH4+ is expected. And the open structure of vanadium compounds satisfies the fast ammoniation/de-ammoniation of NH4+ is also achieved. As a result of these synergistic effects, the BVO//CuHCF full cell retains 80.5 percent of its capacity following 1000 cycling. These achievements provide new ideas for developing low-cost and long-life AIBs.
Aqueous rechargeable ammonium-ion batteries (AIBs) have drew considerable attention because of their capacity for high rates, low cost, and high safety. However, developing desired electrodes requiring stable structure in the aqueous fast ammoniation/de-ammoniation becomes urgent. Herein, an ammonium ion full battery using Cu3[Fe(CN)6]2 (CuHCF) acting to be a cathode and barium vanadate (BVO) acting to be an anode is described. Its excellent electrochemical behavior of Prussian blue analogs and the perfectly matched lattice structure of NH4+ is expected. And the open structure of vanadium compounds satisfies the fast ammoniation/de-ammoniation of NH4+ is also achieved. As a result of these synergistic effects, the BVO//CuHCF full cell retains 80.5 percent of its capacity following 1000 cycling. These achievements provide new ideas for developing low-cost and long-life AIBs.
2024, 35(1): 108462
doi: 10.1016/j.cclet.2023.108462
Abstract:
Paper-based biosensors are widely employed in point-of-care testing (POCT) due to their convenience, portability, low cost, and ease of use. This study reports an integrated distance-based paper biosensor fabricated with a mesoporous membrane coated with stimuli-responsive polymer. The detection of α-amylase (AMY) using amylopectin-coated mesoporous membrane is demonstrated as an example. After introducing the AMY solution, it is observed that the aqueous solution flows along the paper strip due to AMY-catalyzed hydrolysis of amylopectin. The flow distance is proportional to the concentration of AMY with a detection limit as low as 4 mU/mL. In addition, the detection of AMY is demonstrated in human serum. Furthermore, the inhibitory effect of acarbose on AMY is evaluated. This reagent-free and disposable biosensor allows single-step rapid detection of the analyte. This approach is very promising for the development of user-friendly, equipment-free, and cost-effective biosensors with remarkable sensitivity and excellent selectivity for disease diagnosis and hypoglycemic drug screening.
Paper-based biosensors are widely employed in point-of-care testing (POCT) due to their convenience, portability, low cost, and ease of use. This study reports an integrated distance-based paper biosensor fabricated with a mesoporous membrane coated with stimuli-responsive polymer. The detection of α-amylase (AMY) using amylopectin-coated mesoporous membrane is demonstrated as an example. After introducing the AMY solution, it is observed that the aqueous solution flows along the paper strip due to AMY-catalyzed hydrolysis of amylopectin. The flow distance is proportional to the concentration of AMY with a detection limit as low as 4 mU/mL. In addition, the detection of AMY is demonstrated in human serum. Furthermore, the inhibitory effect of acarbose on AMY is evaluated. This reagent-free and disposable biosensor allows single-step rapid detection of the analyte. This approach is very promising for the development of user-friendly, equipment-free, and cost-effective biosensors with remarkable sensitivity and excellent selectivity for disease diagnosis and hypoglycemic drug screening.
2024, 35(1): 108472
doi: 10.1016/j.cclet.2023.108472
Abstract:
Electrosynthesis of hydrogen peroxide (H2O2) is an on-site method that enables independent distribution applications in many fields due to its small-scale and sustainable features. The crucial point remains developing highly active, selective and cost-effective electrocatalysts. The electrosynthesis of H2O2 in acidic media is more practical owing to its stability and no need for further purification. We herein report a phosphorus and selenium tuning Co-based non-precious catalyst (CoPSe) toward two-electron oxygen reduction reaction (2e– ORR) to produce H2O2 in acidic media. The starting point of using both P and Se is finding a balance between strong ORR activity of CoSe and weak activity of CoP. The results demonstrated that the CoPSe catalyst exhibited the optimized 2e– ORR activity compared with CoP and CoSe. It disclosed an onset potential of 0.68 V and the H2O2 selectivity 76%-85% in a wide potential range (0–0.5 V). Notably, the CoPSe catalyst overcomes a significant challenge of a narrow-range selectivity for transition-metal based 2e– ORR catalysts. Finally, combining with electro-Fenton reaction, an on-site system was constructed for efficient degradation of organic pollutants. This work provides a promising non-precious Co-based electrocatalyst for the electrosynthesis of H2O2 in acidic media.
Electrosynthesis of hydrogen peroxide (H2O2) is an on-site method that enables independent distribution applications in many fields due to its small-scale and sustainable features. The crucial point remains developing highly active, selective and cost-effective electrocatalysts. The electrosynthesis of H2O2 in acidic media is more practical owing to its stability and no need for further purification. We herein report a phosphorus and selenium tuning Co-based non-precious catalyst (CoPSe) toward two-electron oxygen reduction reaction (2e– ORR) to produce H2O2 in acidic media. The starting point of using both P and Se is finding a balance between strong ORR activity of CoSe and weak activity of CoP. The results demonstrated that the CoPSe catalyst exhibited the optimized 2e– ORR activity compared with CoP and CoSe. It disclosed an onset potential of 0.68 V and the H2O2 selectivity 76%-85% in a wide potential range (0–0.5 V). Notably, the CoPSe catalyst overcomes a significant challenge of a narrow-range selectivity for transition-metal based 2e– ORR catalysts. Finally, combining with electro-Fenton reaction, an on-site system was constructed for efficient degradation of organic pollutants. This work provides a promising non-precious Co-based electrocatalyst for the electrosynthesis of H2O2 in acidic media.
2024, 35(1): 108475
doi: 10.1016/j.cclet.2023.108475
Abstract:
Photocatalytic activation of peroxymonosulfate (PMS) has garnered a lot of interest in the field of wastewater treatment. Herein, a plasmonic Ag nanoparticles decorated MIL-101(Fe) hybrid was synthesized through a photodeposition process. Upon light irradiation, the Ag/MIL-101(Fe) exhibit reinforced photocatalytic activities for elimination of bisphenol A (BPA) with PMS. The optimized 2.0% Ag/MIL-101(Fe) composite presented the highest photocatalytic activity with kinetic constant k of 0.102 min−1, which was about 10-fold of the pristine MIL-101(Fe). Loading of plasmonic Ag into MIL-101(Fe) boosts photoinduced carrier separation and accelerates PMS activation to generate strong oxidative radicals. Photoelectrochemical tests and multiple spectroscopic studies confirmed the promoted charge carrier separation and transfer capability of Ag/MIL-101(Fe). Combining the results of radical trapping experiments and electron spin resonance (ESR), the formed SO4•−, •OH, •O2− and 1O2 had a significant role in the photocatalytic process. According to intermediate study, the degradation pathway was studied, and the possible mechanism was proposed.
Photocatalytic activation of peroxymonosulfate (PMS) has garnered a lot of interest in the field of wastewater treatment. Herein, a plasmonic Ag nanoparticles decorated MIL-101(Fe) hybrid was synthesized through a photodeposition process. Upon light irradiation, the Ag/MIL-101(Fe) exhibit reinforced photocatalytic activities for elimination of bisphenol A (BPA) with PMS. The optimized 2.0% Ag/MIL-101(Fe) composite presented the highest photocatalytic activity with kinetic constant k of 0.102 min−1, which was about 10-fold of the pristine MIL-101(Fe). Loading of plasmonic Ag into MIL-101(Fe) boosts photoinduced carrier separation and accelerates PMS activation to generate strong oxidative radicals. Photoelectrochemical tests and multiple spectroscopic studies confirmed the promoted charge carrier separation and transfer capability of Ag/MIL-101(Fe). Combining the results of radical trapping experiments and electron spin resonance (ESR), the formed SO4•−, •OH, •O2− and 1O2 had a significant role in the photocatalytic process. According to intermediate study, the degradation pathway was studied, and the possible mechanism was proposed.
2024, 35(1): 108476
doi: 10.1016/j.cclet.2023.108476
Abstract:
Fluorescent silicon quantum dots (Si QDs) were hydrothermally synthesized from a mixture of 3(2-aminoethylamino) propyl (dimethoxymethylsilane) (AEAPDMMS) and poly(vinylpyrrolidine) (PVP). The resulting Si QDs exhibited good water solubility and high stability. Under the optimized conditions, the probe revealed an excellent linear fluorescence quenching effect on Co2+ ranging from 1 µmol/L to 120 µmol/L with a limit of detection of 0.37 µmol/L (based on 3 s/k). The quenching mechanism was studied, showing that static quenching (SQE) causes the main effect. Furthermore, the test paper based on Si QDs was prepared, which is cost-effective, high sensitivity, good selectivity, easy to use and show excellent anti-interference capability. This method was applied to analyze the content of Co2+ in environmental water samples with satisfying results.
Fluorescent silicon quantum dots (Si QDs) were hydrothermally synthesized from a mixture of 3(2-aminoethylamino) propyl (dimethoxymethylsilane) (AEAPDMMS) and poly(vinylpyrrolidine) (PVP). The resulting Si QDs exhibited good water solubility and high stability. Under the optimized conditions, the probe revealed an excellent linear fluorescence quenching effect on Co2+ ranging from 1 µmol/L to 120 µmol/L with a limit of detection of 0.37 µmol/L (based on 3 s/k). The quenching mechanism was studied, showing that static quenching (SQE) causes the main effect. Furthermore, the test paper based on Si QDs was prepared, which is cost-effective, high sensitivity, good selectivity, easy to use and show excellent anti-interference capability. This method was applied to analyze the content of Co2+ in environmental water samples with satisfying results.
2024, 35(1): 108480
doi: 10.1016/j.cclet.2023.108480
Abstract:
A H4SiW12O40-catalyzed three-component tandem reaction of 2-acylbenzoic acids, primary amines and phosphine oxides to form 3,3-disubstituted isoindolinones was developed. By employing H4SiW12O40 as the catalyst and dimethyl carbonate (DMC) as the solvent, a diverse range of 2-acylbenzoic acid derivatives and primary amines worked well to give the C3-phosphinoyl-functionalized 3,3-disubstituted isoindolinones with the yield range of 61%-87%. Advantages of this transformation include green catalyst and solvent, available starting materials, broad substrate scope, high efficiency and operational simplicity with water as the sole by-product. The strategy achieved an efficient and green molecular fragment assembly to access isoindolinones, which would provide opportunities for the synthesis of potential biologically active molecules in a green manner.
A H4SiW12O40-catalyzed three-component tandem reaction of 2-acylbenzoic acids, primary amines and phosphine oxides to form 3,3-disubstituted isoindolinones was developed. By employing H4SiW12O40 as the catalyst and dimethyl carbonate (DMC) as the solvent, a diverse range of 2-acylbenzoic acid derivatives and primary amines worked well to give the C3-phosphinoyl-functionalized 3,3-disubstituted isoindolinones with the yield range of 61%-87%. Advantages of this transformation include green catalyst and solvent, available starting materials, broad substrate scope, high efficiency and operational simplicity with water as the sole by-product. The strategy achieved an efficient and green molecular fragment assembly to access isoindolinones, which would provide opportunities for the synthesis of potential biologically active molecules in a green manner.
2024, 35(1): 108493
doi: 10.1016/j.cclet.2023.108493
Abstract:
Drug loading capacity is very important in the construction of targeted drug delivery systems (TDDSs) for the improvement of drug delivery efficiency. However, the drug-loading capacity of most nanomaterials is non-idealistic, and developing the high drug-loading TDDSs is still a critical challenge. In this work, an ultrahigh loading system (denoted as HMPB2) was prepared via J-aggregation of an aza-boron dipyrromethene derivative (Bod) by using hollow MnO2 modified with glucosamine pillar[5]arene as a carrier, which was demonstrated to have typical J-aggregate absorption of Bod, specific cancer cells targeting ability, negligible dark cytotoxicity, and potent phototoxicity. This work provides a successful example to construct an ultrahigh drug-loading system via J-aggregation for targeted delivery.
Drug loading capacity is very important in the construction of targeted drug delivery systems (TDDSs) for the improvement of drug delivery efficiency. However, the drug-loading capacity of most nanomaterials is non-idealistic, and developing the high drug-loading TDDSs is still a critical challenge. In this work, an ultrahigh loading system (denoted as HMPB2) was prepared via J-aggregation of an aza-boron dipyrromethene derivative (Bod) by using hollow MnO2 modified with glucosamine pillar[5]arene as a carrier, which was demonstrated to have typical J-aggregate absorption of Bod, specific cancer cells targeting ability, negligible dark cytotoxicity, and potent phototoxicity. This work provides a successful example to construct an ultrahigh drug-loading system via J-aggregation for targeted delivery.
2024, 35(1): 108494
doi: 10.1016/j.cclet.2023.108494
Abstract:
Droplet manipulation on an open surface has great potential in chemical analysis and biomedicine engineering. However, most of the reported platforms designed for the manipulation of water droplets cannot thoroughly solve the problem of droplet evaporation. Herein, we report a shape-reconfigurable micropillar array chip for the manipulation of water droplets, oil droplets and water-in-oil droplets. Water-in-oil droplets provide an enclosed space for water droplets, preventing the evaporation in an open environment. Perfluoropolyether coated on the surface of the chip effectively reduces the droplet movement resistance. The micropillar array chip has light and magnetic dual-response due to the Fe3O4 nanoparticles and the reduced iron powder mixed in the shape-memory polymer. The micropillars irradiated by a near-infrared laser bend under the magnetic force, while the unirradiated micropillars still keep their original shape. In the absence of a magnetic field, when the micropillars in a temporary shape are irradiated by the near-infrared laser to the transition temperature, the micropillars return to their initial shape. In this process, the surface morphology gradient caused by the deformation of the micropillars and the surface tension gradient caused by the temperature change jointly produce the driving force of droplet movement.
Droplet manipulation on an open surface has great potential in chemical analysis and biomedicine engineering. However, most of the reported platforms designed for the manipulation of water droplets cannot thoroughly solve the problem of droplet evaporation. Herein, we report a shape-reconfigurable micropillar array chip for the manipulation of water droplets, oil droplets and water-in-oil droplets. Water-in-oil droplets provide an enclosed space for water droplets, preventing the evaporation in an open environment. Perfluoropolyether coated on the surface of the chip effectively reduces the droplet movement resistance. The micropillar array chip has light and magnetic dual-response due to the Fe3O4 nanoparticles and the reduced iron powder mixed in the shape-memory polymer. The micropillars irradiated by a near-infrared laser bend under the magnetic force, while the unirradiated micropillars still keep their original shape. In the absence of a magnetic field, when the micropillars in a temporary shape are irradiated by the near-infrared laser to the transition temperature, the micropillars return to their initial shape. In this process, the surface morphology gradient caused by the deformation of the micropillars and the surface tension gradient caused by the temperature change jointly produce the driving force of droplet movement.
2024, 35(1): 108514
doi: 10.1016/j.cclet.2023.108514
Abstract:
New pollutant pharmaceutical and personal care products (PPCPs), especially antiviral drugs, have received increasing attention not only due to their increase in usage after the outbreak of COVID-19 epidemics but also due to their adverse impacts on water ecological environment. Electro-Fenton technology is an effective method to remove PPCPs from water. Novel particle electrodes (MMT/rGO/Fe3O4) were synthesized by depositing Fe3O4 nanoparticles on reduced graphene oxide modified montmorillonite and acted as catalysts to promote oxidation performance in a three-dimensional electro-Fenton (3D-EF) system. The electrodes combined the catalytic property of Fe3O4, hydrophilicity of montmorillonite and electrical conductivity of graphene oxides, and applied for the degradation of Acyclovir (ACV) with high efficiency and ease of operation. At optimal condition, the degradation rate of ACV reached 100% within 120 min, and the applicable pH range could be 3 to 11 in the 3D-EF system. The stability and reusability of MMT/rGO/Fe3O4 particle electrodes were also studied, the removal rate of ACV remained at 92% after 10 cycles, which was just slightly lower than that of the first cycle. Potential degradation mechanisms were also proposed by methanol quenching tests and FT-ICR-MS.
New pollutant pharmaceutical and personal care products (PPCPs), especially antiviral drugs, have received increasing attention not only due to their increase in usage after the outbreak of COVID-19 epidemics but also due to their adverse impacts on water ecological environment. Electro-Fenton technology is an effective method to remove PPCPs from water. Novel particle electrodes (MMT/rGO/Fe3O4) were synthesized by depositing Fe3O4 nanoparticles on reduced graphene oxide modified montmorillonite and acted as catalysts to promote oxidation performance in a three-dimensional electro-Fenton (3D-EF) system. The electrodes combined the catalytic property of Fe3O4, hydrophilicity of montmorillonite and electrical conductivity of graphene oxides, and applied for the degradation of Acyclovir (ACV) with high efficiency and ease of operation. At optimal condition, the degradation rate of ACV reached 100% within 120 min, and the applicable pH range could be 3 to 11 in the 3D-EF system. The stability and reusability of MMT/rGO/Fe3O4 particle electrodes were also studied, the removal rate of ACV remained at 92% after 10 cycles, which was just slightly lower than that of the first cycle. Potential degradation mechanisms were also proposed by methanol quenching tests and FT-ICR-MS.
2024, 35(1): 108522
doi: 10.1016/j.cclet.2023.108522
Abstract:
Alcohol consumption is one of the leading causes of death worldwide. Adolescence is a critical period of structural and functional maturation of the brain. Adolescent alcohol use can alter epigenetic modifications. However, little is known on the long-term effects of alcohol consumption during adolescence on RNA epigenetic modifications in brain. Herein, we systematically explored the long-term effects of alcohol exposure during adolescence on small RNA modifications in adult rat brain tissues by comprehensive liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. We totally detected 26 modifications in small RNA of brain tissues. Notably, we observed most of these modifications were decreased in brain tissues. These results suggest that alcohol exposure during adolescence may impose a long-lasting impact on RNA modifications in brain tissues. This is the first report that alcohol use during adolescence can alter RNA modifications in adult brain. Collectively, this study suggests a long-term adverse effects of alcohol consumption on brain from RNA epigenetics angle by comprehensive mass spectrometry analysis.
Alcohol consumption is one of the leading causes of death worldwide. Adolescence is a critical period of structural and functional maturation of the brain. Adolescent alcohol use can alter epigenetic modifications. However, little is known on the long-term effects of alcohol consumption during adolescence on RNA epigenetic modifications in brain. Herein, we systematically explored the long-term effects of alcohol exposure during adolescence on small RNA modifications in adult rat brain tissues by comprehensive liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. We totally detected 26 modifications in small RNA of brain tissues. Notably, we observed most of these modifications were decreased in brain tissues. These results suggest that alcohol exposure during adolescence may impose a long-lasting impact on RNA modifications in brain tissues. This is the first report that alcohol use during adolescence can alter RNA modifications in adult brain. Collectively, this study suggests a long-term adverse effects of alcohol consumption on brain from RNA epigenetics angle by comprehensive mass spectrometry analysis.
2024, 35(1): 108532
doi: 10.1016/j.cclet.2023.108532
Abstract:
To achieve a lower detection limit has always been a goal of analytical chemists. Herein, we demonstrate the first picomolar level detection capability for Fe3+ ion via luminescence detection technology. The results of structural analysis and theoretical calculation show that Fe3+ ions are adsorbed on the central node of Eu-DBM (DBM = dibenzoylmethane) sensor in the form of single ion at ultralow concentration. Subsequently, the pathways of photo-induced charge and energy transfer of the obtained Eu-DBM@Fe3+ material have been changed, from the initial DBM-to-Eu3+ before Fe3+ adsorption to the ultimate DBM-to-Fe3+ after adsorption process, which quenches the luminescence of Eu3+ ion. This work not only obtains the highly sensitive luminescence detection ability, but also innovatively proposes the single-ion adsorption mechanism, both of which have important scientific and application values for the development of more efficient detection agents in the future.
To achieve a lower detection limit has always been a goal of analytical chemists. Herein, we demonstrate the first picomolar level detection capability for Fe3+ ion via luminescence detection technology. The results of structural analysis and theoretical calculation show that Fe3+ ions are adsorbed on the central node of Eu-DBM (DBM = dibenzoylmethane) sensor in the form of single ion at ultralow concentration. Subsequently, the pathways of photo-induced charge and energy transfer of the obtained Eu-DBM@Fe3+ material have been changed, from the initial DBM-to-Eu3+ before Fe3+ adsorption to the ultimate DBM-to-Fe3+ after adsorption process, which quenches the luminescence of Eu3+ ion. This work not only obtains the highly sensitive luminescence detection ability, but also innovatively proposes the single-ion adsorption mechanism, both of which have important scientific and application values for the development of more efficient detection agents in the future.
2024, 35(1): 108545
doi: 10.1016/j.cclet.2023.108545
Abstract:
Radiation damage can cause a series of gastrointestinal (GI) tract diseases. The development of safe and effective GI tract radioprotectants still remains a great challenge clinically. Here, we firstly report an oral radioprotectant Gel@GYY that integrates a porous gelatin-based (Gel) hydrogel and a pH-responsive hydrogen sulfide (H2S) donor GYY4137 (morpholin-4-ium 4 methoxyphenyl(morpholino) phosphinodithioate). Gel@GYY has a remarkable adhesion ability and long retention time, which not only enables responsive release of low-dose H2S in stomach and subsequently sustained release of H2S in the whole intestinal tract especially in the colon, but also ensures a close contact between H2S and GI tract. The released H2S can effectively scavenge free radicals induced by X-ray radiation, reduce lipid peroxidation level, repair DNA damage and recover vital superoxide dismutase and glutathione peroxidase activities. Meanwhile, the released H2S inhibits radiation-induced activation of nuclear factor κB (NF-κB), thus reducing inflammatory cytokines levels in GI tract. After treatment, Gel@GYY displays efficient excretion from mice body due to its biodegradability. This work provides a new insight for therapeutic application of intelligent H2S-releasing oral delivery system and potential alternative to clinical GI physical damage protectant.
Radiation damage can cause a series of gastrointestinal (GI) tract diseases. The development of safe and effective GI tract radioprotectants still remains a great challenge clinically. Here, we firstly report an oral radioprotectant Gel@GYY that integrates a porous gelatin-based (Gel) hydrogel and a pH-responsive hydrogen sulfide (H2S) donor GYY4137 (morpholin-4-ium 4 methoxyphenyl(morpholino) phosphinodithioate). Gel@GYY has a remarkable adhesion ability and long retention time, which not only enables responsive release of low-dose H2S in stomach and subsequently sustained release of H2S in the whole intestinal tract especially in the colon, but also ensures a close contact between H2S and GI tract. The released H2S can effectively scavenge free radicals induced by X-ray radiation, reduce lipid peroxidation level, repair DNA damage and recover vital superoxide dismutase and glutathione peroxidase activities. Meanwhile, the released H2S inhibits radiation-induced activation of nuclear factor κB (NF-κB), thus reducing inflammatory cytokines levels in GI tract. After treatment, Gel@GYY displays efficient excretion from mice body due to its biodegradability. This work provides a new insight for therapeutic application of intelligent H2S-releasing oral delivery system and potential alternative to clinical GI physical damage protectant.
2024, 35(1): 108553
doi: 10.1016/j.cclet.2023.108553
Abstract:
Unnatural amino acids (UAAs) have broad applications in pharmaceutical sciences and biological studies. Current synthetic methods for UAAs mainly rely on asymmetric catalysis and often require several steps. There is a lack of direct and simple methods. To address this challenge, we designed the LADA (labeling-activation-desulfurization-addition) strategy: selective labeling and activation of cysteine residues, the photocatalytic desulfurization and the subsequent radical addition to alkenes. Although composed of two steps, it is one-pot synthesis and has advantages such as high functional group tolerance, biocompatible reaction condition, and retained stereochemistry. This highly efficient strategy was successfully applied in the direct synthesis of unnatural amino acids and modifications of peptides with more than 50 examples.
Unnatural amino acids (UAAs) have broad applications in pharmaceutical sciences and biological studies. Current synthetic methods for UAAs mainly rely on asymmetric catalysis and often require several steps. There is a lack of direct and simple methods. To address this challenge, we designed the LADA (labeling-activation-desulfurization-addition) strategy: selective labeling and activation of cysteine residues, the photocatalytic desulfurization and the subsequent radical addition to alkenes. Although composed of two steps, it is one-pot synthesis and has advantages such as high functional group tolerance, biocompatible reaction condition, and retained stereochemistry. This highly efficient strategy was successfully applied in the direct synthesis of unnatural amino acids and modifications of peptides with more than 50 examples.
2024, 35(1): 108555
doi: 10.1016/j.cclet.2023.108555
Abstract:
DNA circuits are powerful tools in various applications such as logical computation, molecular diagnosis and synthetic biology. Leakage is a major problem in constructing complex DNA circuits. It directly affects the output signal and harms the circuit's performance significantly. In the traditional DNA circuits, the gate complex is a duplex structure. There are insufficient energy barriers to prevent spontaneous detachment of strands, resulting in a leak prone. Herein, we have developed triplex-structure based DNA circuit with ultra-low leakage and high signal-to-noise ratio (SNR). The triplex structure improves the stability in the absence of input. At the same time, the driving force of the strand displacement cascades reduces the influence of the triplex structure on the desired reaction. The SNR of the DNA circuit was increased to 695, while the desired reaction rate remained 90% of the conventional translator circuit. The triplex-structure mediated leakage prevention strategy was further tested at different temperatures and in DNA translator and seesaw circuits. We also constructed modular basic logic gates with a high efficiency and low leakage. On this basis, we further constructed triplex-structure based tertiary DNA logic circuits, and the SNR reached 295, which, to the best of our knowledge, was among the highest of the field. We believe that our scheme provides a novel, valid, and general tool for reducing leakages, and we anticipate that it will be widely adopted in DNA nanotechnology.
DNA circuits are powerful tools in various applications such as logical computation, molecular diagnosis and synthetic biology. Leakage is a major problem in constructing complex DNA circuits. It directly affects the output signal and harms the circuit's performance significantly. In the traditional DNA circuits, the gate complex is a duplex structure. There are insufficient energy barriers to prevent spontaneous detachment of strands, resulting in a leak prone. Herein, we have developed triplex-structure based DNA circuit with ultra-low leakage and high signal-to-noise ratio (SNR). The triplex structure improves the stability in the absence of input. At the same time, the driving force of the strand displacement cascades reduces the influence of the triplex structure on the desired reaction. The SNR of the DNA circuit was increased to 695, while the desired reaction rate remained 90% of the conventional translator circuit. The triplex-structure mediated leakage prevention strategy was further tested at different temperatures and in DNA translator and seesaw circuits. We also constructed modular basic logic gates with a high efficiency and low leakage. On this basis, we further constructed triplex-structure based tertiary DNA logic circuits, and the SNR reached 295, which, to the best of our knowledge, was among the highest of the field. We believe that our scheme provides a novel, valid, and general tool for reducing leakages, and we anticipate that it will be widely adopted in DNA nanotechnology.
2024, 35(1): 108556
doi: 10.1016/j.cclet.2023.108556
Abstract:
Implantable system maximizes drug concentration and continuously releases drugs near the tumor, which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer. In this work, a novel polysaccharide supramolecular injectable hydrogel (CCA hydrogels for short) is rapidly constructed by simply mixing cationic chitosan, anionic sulfobutyl ether β-cyclodextrin (SBE-β-CD) and a trace amount of silver ions. The injected hydrogel reconstituted and regained its shape in less than 1 h, and it can still maintain the elasticity suitable for the human body. By packaging the drug directly, the gel achieves a high concentration of doxorubicin, an anticancer drug. Using MB49-luc cells as the model of bladder tumor for anti-tumor in vivo, the CCA-DOX gel has obvious inhibitory effect on bladder tumor, and its inhibitory effect is much greater than that of free DOX. Therefore, this self-healing injectable hydrogel has great potential for in situ treatment of bladder cancer.
Implantable system maximizes drug concentration and continuously releases drugs near the tumor, which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer. In this work, a novel polysaccharide supramolecular injectable hydrogel (CCA hydrogels for short) is rapidly constructed by simply mixing cationic chitosan, anionic sulfobutyl ether β-cyclodextrin (SBE-β-CD) and a trace amount of silver ions. The injected hydrogel reconstituted and regained its shape in less than 1 h, and it can still maintain the elasticity suitable for the human body. By packaging the drug directly, the gel achieves a high concentration of doxorubicin, an anticancer drug. Using MB49-luc cells as the model of bladder tumor for anti-tumor in vivo, the CCA-DOX gel has obvious inhibitory effect on bladder tumor, and its inhibitory effect is much greater than that of free DOX. Therefore, this self-healing injectable hydrogel has great potential for in situ treatment of bladder cancer.
2024, 35(1): 108566
doi: 10.1016/j.cclet.2023.108566
Abstract:
A new strategy to induce vesicle fusion has been developed by employing pillar[5]arene derivatives that were channel-like and were prepared by appending side chains onto pillar[5]arenes backbones. The channels feature with hydrophilic negatively and positively charged groups at both ends and hydrophobic Trp residues at the outer surface, which endows the channels with amphiphilicity. The zwitterionic amphiphilic channels could spontaneously incorporate into the bilayer membranes of lipid vesicles to induce vesicle fusion driven by the electrostatic interactions between negatively charged and positively charged groups.
A new strategy to induce vesicle fusion has been developed by employing pillar[5]arene derivatives that were channel-like and were prepared by appending side chains onto pillar[5]arenes backbones. The channels feature with hydrophilic negatively and positively charged groups at both ends and hydrophobic Trp residues at the outer surface, which endows the channels with amphiphilicity. The zwitterionic amphiphilic channels could spontaneously incorporate into the bilayer membranes of lipid vesicles to induce vesicle fusion driven by the electrostatic interactions between negatively charged and positively charged groups.
2024, 35(1): 108580
doi: 10.1016/j.cclet.2023.108580
Abstract:
Fast Fe(Ⅲ)/Fe(Ⅱ) circulation in heterogeneous peroxymonosulfate (PMS) activation remains as a bottleneck issue that restricts the development of PMS based advanced oxidation processes. Herein, we proposed a facile ammonia reduction strategy and synthesized a novel FeVO3-x catalysts to activate PMS for the degradation of a typical pharmaceutical, carbamazepine (CBZ). Rapid CBZ removal could be achieved within 10 min, which outperforms most of the other iron or vanadium-based catalysts. Electron paramagnetic resonance analysis and chemical probe experiments revealed SO4•−, •OH, O2•− and high valent iron (Fe(Ⅳ)) were all generated in this system, but SO4•− and Fe(Ⅳ) primarily contributed to the degradation of CBZ. Besides, X-ray photoelectron spectroscopy and X-ray adsorption spectroscopy indicated that both the generated low-valent V provides and oxygen vacancy acted as superior electron donors and accelerated internal electron transfer via the unsaturated V−O−Fe bond. Finally, the proposed system also exhibited satisfactory performance in practical applications. This work provides a promising platform in heterogeneous PMS activation.
Fast Fe(Ⅲ)/Fe(Ⅱ) circulation in heterogeneous peroxymonosulfate (PMS) activation remains as a bottleneck issue that restricts the development of PMS based advanced oxidation processes. Herein, we proposed a facile ammonia reduction strategy and synthesized a novel FeVO3-x catalysts to activate PMS for the degradation of a typical pharmaceutical, carbamazepine (CBZ). Rapid CBZ removal could be achieved within 10 min, which outperforms most of the other iron or vanadium-based catalysts. Electron paramagnetic resonance analysis and chemical probe experiments revealed SO4•−, •OH, O2•− and high valent iron (Fe(Ⅳ)) were all generated in this system, but SO4•− and Fe(Ⅳ) primarily contributed to the degradation of CBZ. Besides, X-ray photoelectron spectroscopy and X-ray adsorption spectroscopy indicated that both the generated low-valent V provides and oxygen vacancy acted as superior electron donors and accelerated internal electron transfer via the unsaturated V−O−Fe bond. Finally, the proposed system also exhibited satisfactory performance in practical applications. This work provides a promising platform in heterogeneous PMS activation.
2024, 35(1): 108583
doi: 10.1016/j.cclet.2023.108583
Abstract:
Metastable molybdenum carbide (α-MoC), as a catalyst and an excellent support for metal catalysts, has been widely used in thermo/electro-catalytic reactions. However, the selective synthesis of α-MoC remains a great challenge. Herein, a simple one-pot synthetic strategy for the selective preparation of metastable α-MoC is proposed by electrochemical co-reduction of CO2 and MoO3 in a low-temperature eutectic molten carbonate. The synthesized α-MoC shows a reed flower-like morphology. By controlling the electrolysis time and monitoring the phase and morphology of the obtained products, the growth process of α-MoC is revealed, where the carbon matrix is deposited first followed by the growth of α-MoC from the carbon matrix. Moreover, by analyzing the composition of the electrolytic products, the formation mechanism for α-MoC is proposed. In addition, through this one-pot synthetic strategy, S-doped α-MoC is successfully synthesized. Density functional theory (DFT) calculations reveal that S doping enhanced the HER performance of α-MoC by facilitating water absorption and dissociation and weakening the bond energy of Mo-H to accelerate H desorption. The present work not only highlights the valuable utilization of CO2 but also offers a new perspective on the design and controllable synthesis of metal carbides and their derivatives.
Metastable molybdenum carbide (α-MoC), as a catalyst and an excellent support for metal catalysts, has been widely used in thermo/electro-catalytic reactions. However, the selective synthesis of α-MoC remains a great challenge. Herein, a simple one-pot synthetic strategy for the selective preparation of metastable α-MoC is proposed by electrochemical co-reduction of CO2 and MoO3 in a low-temperature eutectic molten carbonate. The synthesized α-MoC shows a reed flower-like morphology. By controlling the electrolysis time and monitoring the phase and morphology of the obtained products, the growth process of α-MoC is revealed, where the carbon matrix is deposited first followed by the growth of α-MoC from the carbon matrix. Moreover, by analyzing the composition of the electrolytic products, the formation mechanism for α-MoC is proposed. In addition, through this one-pot synthetic strategy, S-doped α-MoC is successfully synthesized. Density functional theory (DFT) calculations reveal that S doping enhanced the HER performance of α-MoC by facilitating water absorption and dissociation and weakening the bond energy of Mo-H to accelerate H desorption. The present work not only highlights the valuable utilization of CO2 but also offers a new perspective on the design and controllable synthesis of metal carbides and their derivatives.
2024, 35(1): 108626
doi: 10.1016/j.cclet.2023.108626
Abstract:
Early diagnosis and treatment of cancer requires the development of tools that are both sensitive and selective in detecting spermine. In this study, we presented a "supramolecular cyclization-induced emission enhancement" strategy for the sensitive and selective detection of spermine. A new pillar[5]arene probe (P1) demonstrated excellent solution/solid dual-state emission properties, and the addition of certain spermine (Spm) resulted in fluorescence enhancement due to the synergy of multiple weak interactions that restricted the free motion of P1 in the P1⊃Spm complex. This mechanism was further confirmed by time-resolved spectroscopy, DFT calculations, and IGM analysis. With its low limit of detection and high selectivity, P1 is a promising tool for measuring spermine in artificial urine samples.
Early diagnosis and treatment of cancer requires the development of tools that are both sensitive and selective in detecting spermine. In this study, we presented a "supramolecular cyclization-induced emission enhancement" strategy for the sensitive and selective detection of spermine. A new pillar[5]arene probe (P1) demonstrated excellent solution/solid dual-state emission properties, and the addition of certain spermine (Spm) resulted in fluorescence enhancement due to the synergy of multiple weak interactions that restricted the free motion of P1 in the P1⊃Spm complex. This mechanism was further confirmed by time-resolved spectroscopy, DFT calculations, and IGM analysis. With its low limit of detection and high selectivity, P1 is a promising tool for measuring spermine in artificial urine samples.
2024, 35(1): 108633
doi: 10.1016/j.cclet.2023.108633
Abstract:
Photocatalytic and photoinduced silyl radicals cascade cyclization procedures for the green and simple preparation of fused tetracyclic skeleton silylated indolo[2,1-a]isoquinoline-6(5H)-ones from 2-aryl-N-acryloyl indoles with hydrosilanes are developed. The photocatalytic reaction is carried out with 9,10-dicyanoanthracene (DCA) as an organophotocatalyst and 3-acetoxyquinuclidine as hydrogen atom transfer (HAT) catalyst at room temperature under metal- and oxidant-free conditions. The keys to the success of photoredox-catalytic conversion include (1) the reductive quenching of DCA* [E1/2(*P/P–) = +1.97 V vs. SCE in MeCN] by 3-acetoxyquinuclidine (Ep = +1.22 V vs. SCE in MeCN), and (2) the thermodynamic feasibility of hydrogen atom abstraction from hydridic Si–H bond by electrophilic N+•. Particularly, the simple photoinduced cascade cyclization using (TMS)3SiH with 2-aryl-N-acryloyl indoles was exploited via an electron−donor−acceptor (EDA) complex under visible light irradiation.
Photocatalytic and photoinduced silyl radicals cascade cyclization procedures for the green and simple preparation of fused tetracyclic skeleton silylated indolo[2,1-a]isoquinoline-6(5H)-ones from 2-aryl-N-acryloyl indoles with hydrosilanes are developed. The photocatalytic reaction is carried out with 9,10-dicyanoanthracene (DCA) as an organophotocatalyst and 3-acetoxyquinuclidine as hydrogen atom transfer (HAT) catalyst at room temperature under metal- and oxidant-free conditions. The keys to the success of photoredox-catalytic conversion include (1) the reductive quenching of DCA* [E1/2(*P/P–) = +1.97 V vs. SCE in MeCN] by 3-acetoxyquinuclidine (Ep = +1.22 V vs. SCE in MeCN), and (2) the thermodynamic feasibility of hydrogen atom abstraction from hydridic Si–H bond by electrophilic N+•. Particularly, the simple photoinduced cascade cyclization using (TMS)3SiH with 2-aryl-N-acryloyl indoles was exploited via an electron−donor−acceptor (EDA) complex under visible light irradiation.
2024, 35(1): 108642
doi: 10.1016/j.cclet.2023.108642
Abstract:
N-formylation of amines, a class of synthetically important reactions, is typically conducted using metal catalysts that are relatively expensive or not readily available and usually needs harsh conditions to increase the reaction efficiency. Here, an efficient continuous microflow strategy was developed for the gas-liquid visible-light photocatalytic N-formylation of piperidine, which achieved a reaction yield of 82.97% and a selectivity of > 99% at 12 min using cheap organic dye photocatalyst under mild reaction conditions. The influence of essential parameters, including light intensity, temperature and equivalents of the gas, additive and photocatalyst, on the reaction yield was systematically studied. Furthermore, kinetic investigations were conducted, exhibiting the dependence of reaction rate and equilibrium yield of N-formylpiperidine on light intensity, temperature and photocatalyst equivalent. The microflow photocatalytic approach established in this work, which realized a markedly higher space-time yield than the conventional batch method (37.9 vs. 0.212 mmol h−1 L−1), paves the way for the continuous, green and efficient synthesis of N-formamides.
N-formylation of amines, a class of synthetically important reactions, is typically conducted using metal catalysts that are relatively expensive or not readily available and usually needs harsh conditions to increase the reaction efficiency. Here, an efficient continuous microflow strategy was developed for the gas-liquid visible-light photocatalytic N-formylation of piperidine, which achieved a reaction yield of 82.97% and a selectivity of > 99% at 12 min using cheap organic dye photocatalyst under mild reaction conditions. The influence of essential parameters, including light intensity, temperature and equivalents of the gas, additive and photocatalyst, on the reaction yield was systematically studied. Furthermore, kinetic investigations were conducted, exhibiting the dependence of reaction rate and equilibrium yield of N-formylpiperidine on light intensity, temperature and photocatalyst equivalent. The microflow photocatalytic approach established in this work, which realized a markedly higher space-time yield than the conventional batch method (37.9 vs. 0.212 mmol h−1 L−1), paves the way for the continuous, green and efficient synthesis of N-formamides.
2024, 35(1): 108652
doi: 10.1016/j.cclet.2023.108652
Abstract:
Herein, two antimony sulfates, named RbSb(SO4)2 (1) and CsSb(SO4)2 (2), have been successfully synthesized with the introduction of Sb3+ cation with stereochemically active lone pairs (SCALP) into sulfates by the conventional hydrothermal method. Both two compounds endow short ultraviolet (UV) absorption edges (281 nm and 278 nm, respectively) and large birefringence (0.171@546 nm and 0.174@546 nm, respectively), which means that they are promising short-wave UV optical materials. Interestingly, though both of the two compounds exhibit similar 1D chained structures, and possess the same functional moieties including SbO4 seesaws and SO4 tetrahedral groups, they exhibit significantly opposite macroscopic symmetries, i.e., compound 1 crystallizes in a centrosymmetric (CS) manner (P21/n) and compound 2 in a noncentrosymmetric (NCS) manner (P212121), due to the size of cations [r(Rb+) = 1.56 Å, r(Cs+) = 1.67 Å] affects the orientation of SCALP of the adjacent Sb3+.
Herein, two antimony sulfates, named RbSb(SO4)2 (1) and CsSb(SO4)2 (2), have been successfully synthesized with the introduction of Sb3+ cation with stereochemically active lone pairs (SCALP) into sulfates by the conventional hydrothermal method. Both two compounds endow short ultraviolet (UV) absorption edges (281 nm and 278 nm, respectively) and large birefringence (0.171@546 nm and 0.174@546 nm, respectively), which means that they are promising short-wave UV optical materials. Interestingly, though both of the two compounds exhibit similar 1D chained structures, and possess the same functional moieties including SbO4 seesaws and SO4 tetrahedral groups, they exhibit significantly opposite macroscopic symmetries, i.e., compound 1 crystallizes in a centrosymmetric (CS) manner (P21/n) and compound 2 in a noncentrosymmetric (NCS) manner (P212121), due to the size of cations [r(Rb+) = 1.56 Å, r(Cs+) = 1.67 Å] affects the orientation of SCALP of the adjacent Sb3+.
2024, 35(1): 108738
doi: 10.1016/j.cclet.2023.108738
Abstract:
A sustainable and practical process is presented for the direct synthesis of sodium tanshinone IIA sulfonate (STS). Our approach was inspired by the well-established and industrially applied batch synthetic route for STS production. We constructed a telescoped two-step continuous flow platform. This involved a continuous tanshinone IIA sulfonation and in-line salt formation. For the setup, we constructed a 3D circular cyclone-type microreactor using femtosecond laser micromachining. Compared to the 68% yield for 2 h in batch, the two-step continuous flow had an STS yield of 90%, achieved for a total residence time of < 3.0 min under optimal conditions. The proposed continuous flow method vastly simplified the operation and improved procedural safety, while significantly reducing the required acid content and wastewater production.
A sustainable and practical process is presented for the direct synthesis of sodium tanshinone IIA sulfonate (STS). Our approach was inspired by the well-established and industrially applied batch synthetic route for STS production. We constructed a telescoped two-step continuous flow platform. This involved a continuous tanshinone IIA sulfonation and in-line salt formation. For the setup, we constructed a 3D circular cyclone-type microreactor using femtosecond laser micromachining. Compared to the 68% yield for 2 h in batch, the two-step continuous flow had an STS yield of 90%, achieved for a total residence time of < 3.0 min under optimal conditions. The proposed continuous flow method vastly simplified the operation and improved procedural safety, while significantly reducing the required acid content and wastewater production.
2024, 35(1): 108741
doi: 10.1016/j.cclet.2023.108741
Abstract:
High monomer concentration is a requisite for engendering the aggregation-induced emssion (AIE) phenomenon as well as the formation of supramolecular polymers. Therefore, this is supposed to ensure the generation of AIE supramolecular polymers, wherein the monomer soluability takes effect. Nevertheless, parts of supramolecular monomers are considered as poessessing different soluability towards the same sovlent, through which the polymerzation process is thus hard to proceed. Interfacial polymerzation gets over the soluabilty restriction, providing a facile method for propelling the reaction of thesemonomers. Herein, we had prepared M1 containing tetraphenylethene (TPE) functionalized with two terpyridine derivatives, then making M1 dissolving in CHCl3 to give solutions. Cu2+ solutions were fabricated through dissolving CuCl2 into H2O. Towards mixing those solutions, AIE interfacial supramolecular polymers (AIEISPs) displaying green fluorescence were generated at the interface of two phases on the basis of metal-coordination between terpyridine and Cu2+. These AIEISPs were certificated to possess the stimuli-responsiveness, for which the excessive addition of tetrabutylammonium hydroxide would cause the structure destruction owing to the stronger bonding ability with Cu2+ than that of terpyridine. These fabricated AIEISPs had provided a new avenue to prepare AIE supramolecular polymers.
High monomer concentration is a requisite for engendering the aggregation-induced emssion (AIE) phenomenon as well as the formation of supramolecular polymers. Therefore, this is supposed to ensure the generation of AIE supramolecular polymers, wherein the monomer soluability takes effect. Nevertheless, parts of supramolecular monomers are considered as poessessing different soluability towards the same sovlent, through which the polymerzation process is thus hard to proceed. Interfacial polymerzation gets over the soluabilty restriction, providing a facile method for propelling the reaction of thesemonomers. Herein, we had prepared M1 containing tetraphenylethene (TPE) functionalized with two terpyridine derivatives, then making M1 dissolving in CHCl3 to give solutions. Cu2+ solutions were fabricated through dissolving CuCl2 into H2O. Towards mixing those solutions, AIE interfacial supramolecular polymers (AIEISPs) displaying green fluorescence were generated at the interface of two phases on the basis of metal-coordination between terpyridine and Cu2+. These AIEISPs were certificated to possess the stimuli-responsiveness, for which the excessive addition of tetrabutylammonium hydroxide would cause the structure destruction owing to the stronger bonding ability with Cu2+ than that of terpyridine. These fabricated AIEISPs had provided a new avenue to prepare AIE supramolecular polymers.
2024, 35(1): 108757
doi: 10.1016/j.cclet.2023.108757
Abstract:
Four pillar[5]arene-based bicyclic compounds, so-called molecular universal joint (MUJ), were synthesized by incorporating a bisamide ring containing N, O, or S-heteroatom groups, which served as stimuli-responsive chiroptical molecular devices. The structure of MUJ was confirmed by 1H NMR spectra and single-crystal X-ray diffraction analysis, and their planar-chiral enantiomers were successfully separated. Chiroptical inversion behaviors from in to out configurations triggered by temperature, solvent, and guest complexation were investigated by circular dichroism spectra. Chiroptical inversion could be realized in the presence of adiponitrile in certain solvents due to the solvation effects on the side ring and the threading of the guest into the pillar[5]arene cavity. However, the stronger self-included interactions between the cavity and the inside ring of certain MUJs led to inhibition of the switching.
Four pillar[5]arene-based bicyclic compounds, so-called molecular universal joint (MUJ), were synthesized by incorporating a bisamide ring containing N, O, or S-heteroatom groups, which served as stimuli-responsive chiroptical molecular devices. The structure of MUJ was confirmed by 1H NMR spectra and single-crystal X-ray diffraction analysis, and their planar-chiral enantiomers were successfully separated. Chiroptical inversion behaviors from in to out configurations triggered by temperature, solvent, and guest complexation were investigated by circular dichroism spectra. Chiroptical inversion could be realized in the presence of adiponitrile in certain solvents due to the solvation effects on the side ring and the threading of the guest into the pillar[5]arene cavity. However, the stronger self-included interactions between the cavity and the inside ring of certain MUJs led to inhibition of the switching.
2024, 35(1): 108764
doi: 10.1016/j.cclet.2023.108764
Abstract:
The development of n-type semiconductor is still far behind that of p-type semiconductor on account of the challenges in enhancing carrier mobility and environmental stability. Herein, by blending with the polymers, n-type ultrathin crystalline thin film was successfully prepared by the method of meniscus-guided coating. Remarkably, the n-type crystalline films exhibit ultrathin thickness as low as 5 nm and excellent mobility of 1.58 cm2 V−1 s−1, which is outstanding in currently reported organic n-type transistors. Moreover, the PS layer provides a high-quality interface with ultralow defect which has strong resistance to external interference with excellent long-term stability, paving the way for the application of n-type transistors in logic circuits.
The development of n-type semiconductor is still far behind that of p-type semiconductor on account of the challenges in enhancing carrier mobility and environmental stability. Herein, by blending with the polymers, n-type ultrathin crystalline thin film was successfully prepared by the method of meniscus-guided coating. Remarkably, the n-type crystalline films exhibit ultrathin thickness as low as 5 nm and excellent mobility of 1.58 cm2 V−1 s−1, which is outstanding in currently reported organic n-type transistors. Moreover, the PS layer provides a high-quality interface with ultralow defect which has strong resistance to external interference with excellent long-term stability, paving the way for the application of n-type transistors in logic circuits.
2024, 35(1): 108777
doi: 10.1016/j.cclet.2023.108777
Abstract:
Nucleophilic phosphine and amine catalyst-switched chemodivergent [4 + 1] and [3 + 3] annulations of allenyl imides and β,γ-enones have been developed, furnishing highly substituted 2-cyclopentenone and 2-pyranone derivatives in moderate to excellent yields. Two plausible reaction mechanisms involving two different ketene intermediates have been proposed to explain the observed chemoselectivity. Moreover, by virtue of the α,β-enone substructure of the [4 + 1] adducts, 1,3-dipolar cycloaddition of nitrile imines has been studied in one-pot to provide various fused pyrazoline derivatives.
Nucleophilic phosphine and amine catalyst-switched chemodivergent [4 + 1] and [3 + 3] annulations of allenyl imides and β,γ-enones have been developed, furnishing highly substituted 2-cyclopentenone and 2-pyranone derivatives in moderate to excellent yields. Two plausible reaction mechanisms involving two different ketene intermediates have been proposed to explain the observed chemoselectivity. Moreover, by virtue of the α,β-enone substructure of the [4 + 1] adducts, 1,3-dipolar cycloaddition of nitrile imines has been studied in one-pot to provide various fused pyrazoline derivatives.
2024, 35(1): 108794
doi: 10.1016/j.cclet.2023.108794
Abstract:
A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes, amines and fluoroalkyl iodides. The reaction featured good function group tolerance and a broad substrate scope, which could be extended to the late-stage modification of bioactive molecules. Bactericidal activity of all the compounds against Xanthomonas oryzae pv. oryzae (Xoo) was evaluated. Among them, compound E14 showed significant activity against Xanthomonas oryzae pv. oryzae (Xoo) with half maximal effective concentration (EC50) value of 6.61 µmol/mL. In pot experiments, the results showed that E14 could control rice bacterial blight with protective and curative efficiencies of 37.5% and 63.2% at 200 µg/mL, respectively. Additionally, a plausible mechanism for antibacterial behavior of E14 was proposed by electron microscopy, flow cytometry, reactive oxygen species detection, and biofilm assay. In current work, it can promote the development of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkyl amination compounds as prospective antibacterial agent bearing an intriguing mode of action.
A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes, amines and fluoroalkyl iodides. The reaction featured good function group tolerance and a broad substrate scope, which could be extended to the late-stage modification of bioactive molecules. Bactericidal activity of all the compounds against Xanthomonas oryzae pv. oryzae (Xoo) was evaluated. Among them, compound E14 showed significant activity against Xanthomonas oryzae pv. oryzae (Xoo) with half maximal effective concentration (EC50) value of 6.61 µmol/mL. In pot experiments, the results showed that E14 could control rice bacterial blight with protective and curative efficiencies of 37.5% and 63.2% at 200 µg/mL, respectively. Additionally, a plausible mechanism for antibacterial behavior of E14 was proposed by electron microscopy, flow cytometry, reactive oxygen species detection, and biofilm assay. In current work, it can promote the development of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkyl amination compounds as prospective antibacterial agent bearing an intriguing mode of action.
2024, 35(1): 108835
doi: 10.1016/j.cclet.2023.108835
Abstract:
A general, facile and eco-friendly iron catalysis enables oxidation of unstrained tertiary aromatic alcohols to ketones through C−C bond cleavage even with H2O2 as the oxidant. Notably, this transformation can tolerate oxidation-labile functional groups. The robustness of this method is further demonstrated on the late-stage oxidation of complex bioactive molecules.
A general, facile and eco-friendly iron catalysis enables oxidation of unstrained tertiary aromatic alcohols to ketones through C−C bond cleavage even with H2O2 as the oxidant. Notably, this transformation can tolerate oxidation-labile functional groups. The robustness of this method is further demonstrated on the late-stage oxidation of complex bioactive molecules.
2024, 35(1): 108872
doi: 10.1016/j.cclet.2023.108872
Abstract:
The recent advances in accelerated polymerization of N-carboxyanhydrides (NCAs) offer an effective strategy to simplify the preparation of polypeptide materials. However, the fine-tuning of polymerization kinetics, which is critical to differentiate the main polymerization and the side reactions, remains largely unexplored. Herein we report the modulation of polymerization rate of NCA in a water/oil biphasic system. By altering the aqueous pH, the initial location of the initiators, and the pKa of initiating amines, we observed the change in polymerization time from several minutes to a few hours. Due to the high interfacial activity and low pKa value, controlled polymerization was observed from multi-amine initiators even if they were initially located in the aqueous phase. This work not only improves our understanding on the biphasic polymerization mechanism, but also facilitates preparation of versatile polypeptide materials.
The recent advances in accelerated polymerization of N-carboxyanhydrides (NCAs) offer an effective strategy to simplify the preparation of polypeptide materials. However, the fine-tuning of polymerization kinetics, which is critical to differentiate the main polymerization and the side reactions, remains largely unexplored. Herein we report the modulation of polymerization rate of NCA in a water/oil biphasic system. By altering the aqueous pH, the initial location of the initiators, and the pKa of initiating amines, we observed the change in polymerization time from several minutes to a few hours. Due to the high interfacial activity and low pKa value, controlled polymerization was observed from multi-amine initiators even if they were initially located in the aqueous phase. This work not only improves our understanding on the biphasic polymerization mechanism, but also facilitates preparation of versatile polypeptide materials.
2024, 35(1): 108878
doi: 10.1016/j.cclet.2023.108878
Abstract:
The development of molecular probes or systems with the ability of multiple orthogonal responses is an effective approach to precisely detect biomolecules with similar chemical structures. Herein, we report the synthesis of a water-soluble TPE-based octacationic cage (1) with the compressed TPE-containing bilayer, which endows it with good fluorescence properties and potential conformation chirality. As a result, 1 exhibits molecular recognition for anionic nucleotides within its two “claw”-like cavities to form 1:2 host-guest complexes in water, companying with selective turn-off fluorescence and turn-on CD responses to G/GTP over other nucleotides.
The development of molecular probes or systems with the ability of multiple orthogonal responses is an effective approach to precisely detect biomolecules with similar chemical structures. Herein, we report the synthesis of a water-soluble TPE-based octacationic cage (1) with the compressed TPE-containing bilayer, which endows it with good fluorescence properties and potential conformation chirality. As a result, 1 exhibits molecular recognition for anionic nucleotides within its two “claw”-like cavities to form 1:2 host-guest complexes in water, companying with selective turn-off fluorescence and turn-on CD responses to G/GTP over other nucleotides.
2024, 35(1): 108894
doi: 10.1016/j.cclet.2023.108894
Abstract:
Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme. Despite tremendous endeavor has been devoted to using gold nanoparticles (AuNPs) as conjugation matrix due to its fascinating physico-chemical properties, maintaining enzymatic activity while circumventing cumbersome modification remains a formidable challenge. Herein, the freezing-directed conjugation of enzyme/nano interfaces was constructed without extra reagent. As the proof of concept, glucose oxidase (GOx) was chosen as model enzyme. The one-pot conjugation process can be facilely completed at −20 ℃ under aqueous solution. Moreover, with the loading of GOx on AuNP at freezing, the enzyme exhibited superior catalytic activity and stability upon thermal and pH perturbation. The mechanism of boosted activity was then discussed in detail. It was found that higher loading density under freezing condition and more enzyme tending to bind AuNPs via Au-S bond were the main factors for the superior activity. More importantly, this methodology was universal and can also be applied to other enzyme which contains natural cysteine, such as horseradish peroxidase (HRP) and papain. This facile conjugation strategy accompanied by remarkable bioactivity expand the possibilities for enzymatic biosensing, microdevice and even drug delivery.
Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme. Despite tremendous endeavor has been devoted to using gold nanoparticles (AuNPs) as conjugation matrix due to its fascinating physico-chemical properties, maintaining enzymatic activity while circumventing cumbersome modification remains a formidable challenge. Herein, the freezing-directed conjugation of enzyme/nano interfaces was constructed without extra reagent. As the proof of concept, glucose oxidase (GOx) was chosen as model enzyme. The one-pot conjugation process can be facilely completed at −20 ℃ under aqueous solution. Moreover, with the loading of GOx on AuNP at freezing, the enzyme exhibited superior catalytic activity and stability upon thermal and pH perturbation. The mechanism of boosted activity was then discussed in detail. It was found that higher loading density under freezing condition and more enzyme tending to bind AuNPs via Au-S bond were the main factors for the superior activity. More importantly, this methodology was universal and can also be applied to other enzyme which contains natural cysteine, such as horseradish peroxidase (HRP) and papain. This facile conjugation strategy accompanied by remarkable bioactivity expand the possibilities for enzymatic biosensing, microdevice and even drug delivery.
2024, 35(1): 109106
doi: 10.1016/j.cclet.2023.109106
Abstract:
Carbon nanofibers (CNFs) have received extensive and in-depth studied as anodes for sodium-ion batteries (SIBs), and yet their initial Coulombic efficiency and rate capability remain enormous challenge at practical level. Herein, CNFs anchored with cobalt nanocluster (CNFs-Co) were prepared using chemical vapor deposition and thermal reduction methods. The as-prepared CNFs-Co shows a high initial Coulombic efficiency of 91% and a high specific discharge capacity of 246 mAh/g at 0.1 A/g after 200 cycles as anode for SIBs. Meanwhile, the CNFs-Co anode still delivers a high cycling stability with 108 mAh/g after 1000 cycles at 10 A/g. These excellent electrochemical properties could be attributed to the involved spin state Co, which endows CNFs with large interplanar spacing (0.39 nm) and abundant vacancy defects. Importantly, the spin state Co downshifts the p-band center of carbon and strengthens the Na+ adsorption energy from −2.33 eV to −2.64 eV based on density functional theory calculation. This novel strategy of modulating the carbon electronic structure by the spin state of magnetic metals provides a reference for the development of high-performance carbon-based anode materials.
Carbon nanofibers (CNFs) have received extensive and in-depth studied as anodes for sodium-ion batteries (SIBs), and yet their initial Coulombic efficiency and rate capability remain enormous challenge at practical level. Herein, CNFs anchored with cobalt nanocluster (CNFs-Co) were prepared using chemical vapor deposition and thermal reduction methods. The as-prepared CNFs-Co shows a high initial Coulombic efficiency of 91% and a high specific discharge capacity of 246 mAh/g at 0.1 A/g after 200 cycles as anode for SIBs. Meanwhile, the CNFs-Co anode still delivers a high cycling stability with 108 mAh/g after 1000 cycles at 10 A/g. These excellent electrochemical properties could be attributed to the involved spin state Co, which endows CNFs with large interplanar spacing (0.39 nm) and abundant vacancy defects. Importantly, the spin state Co downshifts the p-band center of carbon and strengthens the Na+ adsorption energy from −2.33 eV to −2.64 eV based on density functional theory calculation. This novel strategy of modulating the carbon electronic structure by the spin state of magnetic metals provides a reference for the development of high-performance carbon-based anode materials.
2024, 35(1): 109108
doi: 10.1016/j.cclet.2023.109108
Abstract:
It is challenging to cooperatively improve the nonlinear optical (NLO) efficiency and the laser-induced damage threshold (LIDT). This work reports a novel IR NLO materials CsInP2S7 (CIPS) designed by combination the strategies of alkali metals substitution and microscopic NLO units PS4 introduction based on AgGaS2. CIPS was composed of strongly distorted [InS6]9- octahedra and [P2S7]4- dimers constructed by corner-sharing [PS4]3-, which increase the NLO efficiency and decrease thermal expansion anisotropy simultaneously. Compared with AgGaS2, CIPS exhibited strong phase matchable NLO response ca. 1.1 × AGS@2.1 µm, high LIDT ca. 20.8 × AgGaS2, and IR transparency up to 15.3 µm. Structural analysis and theoretical investigation confirmed that large SHG effect and ultrahigh LIDT of CIPS originated from the synergistic contribution of [InS6]9- octahedra and [P2S7]4- dimers. These results indicate that CIPS is a promising NLO candidate in the mid-IR region, and this study provides a new approach for developing potential NLO-LIDT compatible materials.
It is challenging to cooperatively improve the nonlinear optical (NLO) efficiency and the laser-induced damage threshold (LIDT). This work reports a novel IR NLO materials CsInP2S7 (CIPS) designed by combination the strategies of alkali metals substitution and microscopic NLO units PS4 introduction based on AgGaS2. CIPS was composed of strongly distorted [InS6]9- octahedra and [P2S7]4- dimers constructed by corner-sharing [PS4]3-, which increase the NLO efficiency and decrease thermal expansion anisotropy simultaneously. Compared with AgGaS2, CIPS exhibited strong phase matchable NLO response ca. 1.1 × AGS@2.1 µm, high LIDT ca. 20.8 × AgGaS2, and IR transparency up to 15.3 µm. Structural analysis and theoretical investigation confirmed that large SHG effect and ultrahigh LIDT of CIPS originated from the synergistic contribution of [InS6]9- octahedra and [P2S7]4- dimers. These results indicate that CIPS is a promising NLO candidate in the mid-IR region, and this study provides a new approach for developing potential NLO-LIDT compatible materials.
2024, 35(1): 109124
doi: 10.1016/j.cclet.2023.109124
Abstract:
The development of core-shell nanoclusters with controllable composition is of utmost importance as the material properties depend on their constituent elements. However, precisely tuning their compositions at the atomic scale is not easily achieved because of the difficulty of using limited macroscopic synthetic methods for atomic-level modulation. In this work, we report an interesting example of precisely regulating the core composition of an inorganic core-shell-type cobalt polyoxoniobate [Co26Nb36O140]32− by controlling reaction conditions, in which the inner Co-core composition could be tune while retaining the outer Nb-shell composition of resulting product, leading to a series of isostructural species with a general formula of {Co26-nNb36+nO140} (n = 0–2). These rare species not only can display good powder and single-crystal proton conductivities, but also might provide helpful and atomic-level insights into the syntheses, structures and composition modifications of inorganic amorphous core-shell heterometal oxide nanoparticles.
The development of core-shell nanoclusters with controllable composition is of utmost importance as the material properties depend on their constituent elements. However, precisely tuning their compositions at the atomic scale is not easily achieved because of the difficulty of using limited macroscopic synthetic methods for atomic-level modulation. In this work, we report an interesting example of precisely regulating the core composition of an inorganic core-shell-type cobalt polyoxoniobate [Co26Nb36O140]32− by controlling reaction conditions, in which the inner Co-core composition could be tune while retaining the outer Nb-shell composition of resulting product, leading to a series of isostructural species with a general formula of {Co26-nNb36+nO140} (n = 0–2). These rare species not only can display good powder and single-crystal proton conductivities, but also might provide helpful and atomic-level insights into the syntheses, structures and composition modifications of inorganic amorphous core-shell heterometal oxide nanoparticles.
2024, 35(1): 109186
doi: 10.1016/j.cclet.2023.109186
Abstract:
Atomization energy (AE) is an important indicator for measuring material stability and reactivity, which refers to the energy change when a polyatomic molecule decomposes into its constituent atoms. Predicting AE based on the structural information of molecules has been a focus of researchers, but existing methods have limitations such as being time-consuming or requiring complex preprocessing and large amounts of training data. Deep learning (DL), a new branch of machine learning (ML), has shown promise in learning internal rules and hierarchical representations of sample data, making it a potential solution for AE prediction. To address this problem, we propose a natural-parameter network (NPN) approach for AE prediction. This method establishes a clearer statistical interpretation of the relationship between the network's output and the given data. We use the Coulomb matrix (CM) method to represent each compound as a structural information matrix. Furthermore, we also designed an end-to-end predictive model. Experimental results demonstrate that our method achieves excellent performance on the QM7 and BC2P datasets, and the mean absolute error (MAE) obtained on the QM7 test set ranges from 0.2 kcal/mol to 3 kcal/mol. The optimal result of our method is approximately an order of magnitude higher than the accuracy of 3 kcal/mol in published works. Additionally, our approach significantly accelerates the prediction time. Overall, this study presents a promising approach to accelerate the process of predicting structures using DL, and provides a valuable contribution to the field of chemical energy prediction.
Atomization energy (AE) is an important indicator for measuring material stability and reactivity, which refers to the energy change when a polyatomic molecule decomposes into its constituent atoms. Predicting AE based on the structural information of molecules has been a focus of researchers, but existing methods have limitations such as being time-consuming or requiring complex preprocessing and large amounts of training data. Deep learning (DL), a new branch of machine learning (ML), has shown promise in learning internal rules and hierarchical representations of sample data, making it a potential solution for AE prediction. To address this problem, we propose a natural-parameter network (NPN) approach for AE prediction. This method establishes a clearer statistical interpretation of the relationship between the network's output and the given data. We use the Coulomb matrix (CM) method to represent each compound as a structural information matrix. Furthermore, we also designed an end-to-end predictive model. Experimental results demonstrate that our method achieves excellent performance on the QM7 and BC2P datasets, and the mean absolute error (MAE) obtained on the QM7 test set ranges from 0.2 kcal/mol to 3 kcal/mol. The optimal result of our method is approximately an order of magnitude higher than the accuracy of 3 kcal/mol in published works. Additionally, our approach significantly accelerates the prediction time. Overall, this study presents a promising approach to accelerate the process of predicting structures using DL, and provides a valuable contribution to the field of chemical energy prediction.
2024, 35(1): 108286
doi: 10.1016/j.cclet.2023.108286
Abstract:
As an emerging star in the family of two-dimensional (2D) materials, 2D transition metal carbides, carbonitrides and nitrides, collectively referred to as MXenes, have large specific surface area, rich active sites, metallic conductivity and adjustable surface chemical properties. These features make MXenes promising candidates for gas-sensing materials. For the past few years, MXene-based sensors have drawn increasing attention due to their enhanced sensor performance. Based on this, this review systematically represents the structure, synthesis methods and properties of MXenes, and summarizes their applications in gas sensors. Firstly, the types, structure, main synthesis methods and properties of MXenes are introduced in a comprehensive way. Next, the corresponding design principle and working mechanism of MXene-based gas sensor are clarified. Subsequently, the sensing performances of pristine MXenes and the MXene-based nanocomposite are discussed. Finally, some future opportunities and challenges of MXene-based sensors are pointed out.
As an emerging star in the family of two-dimensional (2D) materials, 2D transition metal carbides, carbonitrides and nitrides, collectively referred to as MXenes, have large specific surface area, rich active sites, metallic conductivity and adjustable surface chemical properties. These features make MXenes promising candidates for gas-sensing materials. For the past few years, MXene-based sensors have drawn increasing attention due to their enhanced sensor performance. Based on this, this review systematically represents the structure, synthesis methods and properties of MXenes, and summarizes their applications in gas sensors. Firstly, the types, structure, main synthesis methods and properties of MXenes are introduced in a comprehensive way. Next, the corresponding design principle and working mechanism of MXene-based gas sensor are clarified. Subsequently, the sensing performances of pristine MXenes and the MXene-based nanocomposite are discussed. Finally, some future opportunities and challenges of MXene-based sensors are pointed out.
2024, 35(1): 108351
doi: 10.1016/j.cclet.2023.108351
Abstract:
In the process of electrocatalytic water splitting, the management of gaseous products is an important task. Timely detachment of gaseous products from the electrode surface and the electrolyte is beneficial to the reduction of energy consumption of the electrolytic cell. In the existing industrial electrolytic cells, the circulating pump drives the electrolyte flowing to discharge the gaseous products. Up to now, several much more advanced strategies have been explored to deal with the negative effects of bubbles. In this review, we summarized various strategies for bubble detachment, including electrode design, external field imposing and system upgrading. We also elaborated the principle, functional features, practicability, advantages and limitations of each method. Finally, challenges and perspectives are also provided for the further development of advanced bubbles detachment strategies for efficient hydrogen evolution.
In the process of electrocatalytic water splitting, the management of gaseous products is an important task. Timely detachment of gaseous products from the electrode surface and the electrolyte is beneficial to the reduction of energy consumption of the electrolytic cell. In the existing industrial electrolytic cells, the circulating pump drives the electrolyte flowing to discharge the gaseous products. Up to now, several much more advanced strategies have been explored to deal with the negative effects of bubbles. In this review, we summarized various strategies for bubble detachment, including electrode design, external field imposing and system upgrading. We also elaborated the principle, functional features, practicability, advantages and limitations of each method. Finally, challenges and perspectives are also provided for the further development of advanced bubbles detachment strategies for efficient hydrogen evolution.
2024, 35(1): 108360
doi: 10.1016/j.cclet.2023.108360
Abstract:
Viruses are ubiquitous in human life. Some viruses can be used as vectors of genetic engineering and specific pesticides. Other viruses trigger a variety of diseases in humans, animals and plants, resulting in high infection rates and mortality. Therefore, convenient, accurate and rapid detection of viruses is of great significance for the diagnosis and treatment of subsequent diseases. In contrast to traditional methods of detection, which rely on time-consuming and complex techniques such as polymerase chain reaction (PCR), fluorescent probes and imaging methods generate real-time results, with high specificity, and have been widely used in viral detection. In this review, the application of viral fluorescent probes in analyzing the molecular structure, detection and biological imaging is discussed. In particular, we categorized the probes based on their specificity for human and plant viruses, reviewing the latest findings and analyzing their limitations. The potential of fluorescent molecular probes in the treatment of viral disease and environmental analysis, and their possible combinations with protein and immune technology are discussed.
Viruses are ubiquitous in human life. Some viruses can be used as vectors of genetic engineering and specific pesticides. Other viruses trigger a variety of diseases in humans, animals and plants, resulting in high infection rates and mortality. Therefore, convenient, accurate and rapid detection of viruses is of great significance for the diagnosis and treatment of subsequent diseases. In contrast to traditional methods of detection, which rely on time-consuming and complex techniques such as polymerase chain reaction (PCR), fluorescent probes and imaging methods generate real-time results, with high specificity, and have been widely used in viral detection. In this review, the application of viral fluorescent probes in analyzing the molecular structure, detection and biological imaging is discussed. In particular, we categorized the probes based on their specificity for human and plant viruses, reviewing the latest findings and analyzing their limitations. The potential of fluorescent molecular probes in the treatment of viral disease and environmental analysis, and their possible combinations with protein and immune technology are discussed.
2024, 35(1): 108378
doi: 10.1016/j.cclet.2023.108378
Abstract:
The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019 has negatively affected people's lives and productivity. Because the mode of transmission of SARS-CoV-2 is of great concern, this review discusses the sources of virus aerosols and possible transmission routes. First, we discuss virus aerosol collection methods, including natural sedimentation, solid impact, liquid impact, centrifugal, cyclone and electrostatic adsorption methods. Then, we review common virus aerosol detection methods, including virus culture, metabolic detection, nucleic acid-based detection and immunology-based detection methods. Finally, possible solutions for the detection of SARS-CoV-2 aerosols are introduced. Point-of-care testing has long been a focus of attention. In the near future, the development of an instrument that integrates sampling and output results will enable the real-time, automatic monitoring of patients.
The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019 has negatively affected people's lives and productivity. Because the mode of transmission of SARS-CoV-2 is of great concern, this review discusses the sources of virus aerosols and possible transmission routes. First, we discuss virus aerosol collection methods, including natural sedimentation, solid impact, liquid impact, centrifugal, cyclone and electrostatic adsorption methods. Then, we review common virus aerosol detection methods, including virus culture, metabolic detection, nucleic acid-based detection and immunology-based detection methods. Finally, possible solutions for the detection of SARS-CoV-2 aerosols are introduced. Point-of-care testing has long been a focus of attention. In the near future, the development of an instrument that integrates sampling and output results will enable the real-time, automatic monitoring of patients.
2024, 35(1): 108385
doi: 10.1016/j.cclet.2023.108385
Abstract:
Organic long-persistent luminescence (LPL) materials, featuring low preparation cost, eco-friendly synthesis, and easy modification of functional groups, have exhibited extensive applications in information encryption, anti-counterfeiting, and biological imaging. Several design strategies including crystallization-inducement, H-aggregation, and host–guest doping to enhance persistent-room-temperature phosphorescence (RTP) effect by precisely controlling intersystem crossing (ISC) constant and suppressing nonradiative decay rates, those are important strategies to enable LPL performance. Among the strategies, researchers have made several efforts to enhance persistent-RTP effect by host–guest interaction, in which the host matrices provide a rigid environment for phosphor guest molecules. The interaction of the luminescent guest molecules with the host matrix can effectively reduce the vibration and rotation of the luminescent molecules, and suppress the non-radiative inactivation, thereby improving the phosphorescence quantum yield. This review aims to summarize several design strategies of pure organic LPL materials based on persistent-RTP effect through host–guest interaction, and describe some applications of pure organic LPL materials in different fields.
Organic long-persistent luminescence (LPL) materials, featuring low preparation cost, eco-friendly synthesis, and easy modification of functional groups, have exhibited extensive applications in information encryption, anti-counterfeiting, and biological imaging. Several design strategies including crystallization-inducement, H-aggregation, and host–guest doping to enhance persistent-room-temperature phosphorescence (RTP) effect by precisely controlling intersystem crossing (ISC) constant and suppressing nonradiative decay rates, those are important strategies to enable LPL performance. Among the strategies, researchers have made several efforts to enhance persistent-RTP effect by host–guest interaction, in which the host matrices provide a rigid environment for phosphor guest molecules. The interaction of the luminescent guest molecules with the host matrix can effectively reduce the vibration and rotation of the luminescent molecules, and suppress the non-radiative inactivation, thereby improving the phosphorescence quantum yield. This review aims to summarize several design strategies of pure organic LPL materials based on persistent-RTP effect through host–guest interaction, and describe some applications of pure organic LPL materials in different fields.
2024, 35(1): 108418
doi: 10.1016/j.cclet.2023.108418
Abstract:
Methane chemistry is one of the "Holy Grails of catalysis". It is highly desirable but challenge to transform methane into value-added chemicals, because of its high C-H bonding energy (435 kJ/mol), lack of π bonding or unpaired electrons. Currently, commercial methane conversion is usually carried out in harsh conditions with enormous energy input. Photocatalytic partial oxidation of methane to liquid oxygenates (PPOMO) is a future-oriented technology towards realizing high efficiency and high selectivity under mild conditions. The selection of oxidant is crucial to the PPOMO performance. Hence, attentions are paid to the research progress of PPOMO with various oxidants (O2, H2O, H2O2 and other oxidants). Moreover, the activation of the selected oxidants is also highly emphasized. Meanwhile, we summarized the methane activation mechanisms focusing on the C-H bond that was broken mainly by •OH radical, O− specie or photogenerated hole (h+). Finally, the challenges and prospects in this subject are briefly discussed.
Methane chemistry is one of the "Holy Grails of catalysis". It is highly desirable but challenge to transform methane into value-added chemicals, because of its high C-H bonding energy (435 kJ/mol), lack of π bonding or unpaired electrons. Currently, commercial methane conversion is usually carried out in harsh conditions with enormous energy input. Photocatalytic partial oxidation of methane to liquid oxygenates (PPOMO) is a future-oriented technology towards realizing high efficiency and high selectivity under mild conditions. The selection of oxidant is crucial to the PPOMO performance. Hence, attentions are paid to the research progress of PPOMO with various oxidants (O2, H2O, H2O2 and other oxidants). Moreover, the activation of the selected oxidants is also highly emphasized. Meanwhile, we summarized the methane activation mechanisms focusing on the C-H bond that was broken mainly by •OH radical, O− specie or photogenerated hole (h+). Finally, the challenges and prospects in this subject are briefly discussed.
2024, 35(1): 108423
doi: 10.1016/j.cclet.2023.108423
Abstract:
Carbon dots (CDs) have attracted considerable attention as a new type of fluorescent carbon nanomaterial because of their excellent optical properties, biocompatibility, and high electrical conductivity. Research on CDs has been conducted for nearly two decades and has focused on numerous precursors, various synthesis conditions and properties and applications of CDs. Biomass is critical in the green development of CDs because of its low cost, environmental friendliness, and sustainable properties. This review focuses on the advantages and applications of biomass-derived CDs. In addition, the challenges of photobleaching, toxicity, and stability of biomass-based CDs are discussed in detail. Lastly, the prospects and challenges of biomass-derived CDs are highlighted.
Carbon dots (CDs) have attracted considerable attention as a new type of fluorescent carbon nanomaterial because of their excellent optical properties, biocompatibility, and high electrical conductivity. Research on CDs has been conducted for nearly two decades and has focused on numerous precursors, various synthesis conditions and properties and applications of CDs. Biomass is critical in the green development of CDs because of its low cost, environmental friendliness, and sustainable properties. This review focuses on the advantages and applications of biomass-derived CDs. In addition, the challenges of photobleaching, toxicity, and stability of biomass-based CDs are discussed in detail. Lastly, the prospects and challenges of biomass-derived CDs are highlighted.
2024, 35(1): 108432
doi: 10.1016/j.cclet.2023.108432
Abstract:
NH3 in ambient air directly leads to an increase in the aerosol content in the air. These substances lead to the formation of haze to various environmental problems after atmospheric circulation and diffusion. Controlling NH3 emissions caused by ammonia escaping from mobile and industrial sources can effectively reduce the NH3 content in ambient air. Among the various NH3 removal methods, the selective catalytic oxygen method (NH3-SCO) is committed to oxidizing NH3 to environmentally harmless H2O and N2; therefore, it is the most valuable and ideal ammonia removal method. In this review, the characteristics of loaded and core-shell catalysts in NH3-SCO have been reviewed in the context of catalyst structure-activity relationships, and the H2O resistance and SO2 resistance of the catalysts are discussed in the context of practical application conditions. Then the effects of the valence state of the active center, oxygen species on the catalyst surface, dispersion of the active center and acidic sites on the catalyst performance are discussed comprehensively. Finally, the shortcomings of the existing catalysts are summarized and the catalyst development is discussed based on the existing studies.
NH3 in ambient air directly leads to an increase in the aerosol content in the air. These substances lead to the formation of haze to various environmental problems after atmospheric circulation and diffusion. Controlling NH3 emissions caused by ammonia escaping from mobile and industrial sources can effectively reduce the NH3 content in ambient air. Among the various NH3 removal methods, the selective catalytic oxygen method (NH3-SCO) is committed to oxidizing NH3 to environmentally harmless H2O and N2; therefore, it is the most valuable and ideal ammonia removal method. In this review, the characteristics of loaded and core-shell catalysts in NH3-SCO have been reviewed in the context of catalyst structure-activity relationships, and the H2O resistance and SO2 resistance of the catalysts are discussed in the context of practical application conditions. Then the effects of the valence state of the active center, oxygen species on the catalyst surface, dispersion of the active center and acidic sites on the catalyst performance are discussed comprehensively. Finally, the shortcomings of the existing catalysts are summarized and the catalyst development is discussed based on the existing studies.
2024, 35(1): 108438
doi: 10.1016/j.cclet.2023.108438
Abstract:
The past few years have witnessed power conversion efficiency (PCE) of organic solar cells (OSCs) skyrocketing to the value of 20% due to the outstanding advantages of organic photoactive materials. The latter, which consist of donor and acceptor materials, indeed play important roles in OSCs, and particularly one building block has attracted considerable research attention, namely benzothiadiazole (BT). The diversity of OSCs based on the BT structure have indeed sprung up, and the progressive increase in PCE values is more than just eye-catching since it heralds a renewal and bright future of OSCs. This review analyzes significant studies that have led to these remarkable progresses and focuses on the most effective BT small-molecules and BT polymers for OSC reported in the last decades. The pivotal structure–property relationships, donor–acceptor matching criteria, and morphology control approaches are gathered and discussed in this paper. Lastly, we summarize the remaining challenges and offer a personal perspective on the future advance and improvement of OSCs.
The past few years have witnessed power conversion efficiency (PCE) of organic solar cells (OSCs) skyrocketing to the value of 20% due to the outstanding advantages of organic photoactive materials. The latter, which consist of donor and acceptor materials, indeed play important roles in OSCs, and particularly one building block has attracted considerable research attention, namely benzothiadiazole (BT). The diversity of OSCs based on the BT structure have indeed sprung up, and the progressive increase in PCE values is more than just eye-catching since it heralds a renewal and bright future of OSCs. This review analyzes significant studies that have led to these remarkable progresses and focuses on the most effective BT small-molecules and BT polymers for OSC reported in the last decades. The pivotal structure–property relationships, donor–acceptor matching criteria, and morphology control approaches are gathered and discussed in this paper. Lastly, we summarize the remaining challenges and offer a personal perspective on the future advance and improvement of OSCs.
2024, 35(1): 108460
doi: 10.1016/j.cclet.2023.108460
Abstract:
Malignant tumors are the main diseases threatening human life. Using precise theranostics to diagnose and cure tumors has emerged as a new method to improve patient survival. Based on the current development of precise tumor imaging, image-guided tumor therapy has received widespread attention because it is beneficial for developing precise treatment of tumors, has the potential to improve the efficacy of tumor therapy and reduce the incidence of adverse side effects. Nanoprobes, which are nanomaterial functionalized with specific biomolecules, have intrigued intense interest due to their great potential in monitoring biorecognition and biodetection evens. Benefiting from the unique advantages of nanomaterials, including the easy surface functionalization, the unique imaging performances, and the high drug loading capacity, nanoprobes have become a powerful tool to simultaneously realize tumor precise imaging, diagnosis, and therapy. This review introduces the non-invasive tumor precise imaging and highlights the recent advances of image-guided oncotherapy mediated by nanoprobes in anti-tumor drug delivery, tumor precise surgical navigation, chemodynamic therapy, and phototherapy. Finally, a perspective on the challenge and future direction of nanoprobes in imaging-guided tumor theranostics is also discussed.
Malignant tumors are the main diseases threatening human life. Using precise theranostics to diagnose and cure tumors has emerged as a new method to improve patient survival. Based on the current development of precise tumor imaging, image-guided tumor therapy has received widespread attention because it is beneficial for developing precise treatment of tumors, has the potential to improve the efficacy of tumor therapy and reduce the incidence of adverse side effects. Nanoprobes, which are nanomaterial functionalized with specific biomolecules, have intrigued intense interest due to their great potential in monitoring biorecognition and biodetection evens. Benefiting from the unique advantages of nanomaterials, including the easy surface functionalization, the unique imaging performances, and the high drug loading capacity, nanoprobes have become a powerful tool to simultaneously realize tumor precise imaging, diagnosis, and therapy. This review introduces the non-invasive tumor precise imaging and highlights the recent advances of image-guided oncotherapy mediated by nanoprobes in anti-tumor drug delivery, tumor precise surgical navigation, chemodynamic therapy, and phototherapy. Finally, a perspective on the challenge and future direction of nanoprobes in imaging-guided tumor theranostics is also discussed.
2024, 35(1): 108511
doi: 10.1016/j.cclet.2023.108511
Abstract:
Methicillin-resistant Staphylococcus aureus (MRSA), the most common pathogen in hospital and community environments, can cause serious and even fatal infections. The antibiotics currently used for clinical treatment of MRSA have developed resistance, and there is an urgent need to develop new antimicrobials to treat infections caused by MRSA strains. Quinoline analogues play an important role in the development of antimicrobials. Herein, we discussed the current development of antibacterial activities of quinoline analogues, mainly for anti-MRSA activity, and their structure–activity relationships (SARs) from the perspective of using the quinoline nucleus to search for novel potential anti-MRSA candidates. Additionally, the mechanisms of some representative quinoline analogues against MRSA were clarified. Altogether, this review could provide further insights for the rational development of quinoline-based antibacterial drugs, especially against MRSA.
Methicillin-resistant Staphylococcus aureus (MRSA), the most common pathogen in hospital and community environments, can cause serious and even fatal infections. The antibiotics currently used for clinical treatment of MRSA have developed resistance, and there is an urgent need to develop new antimicrobials to treat infections caused by MRSA strains. Quinoline analogues play an important role in the development of antimicrobials. Herein, we discussed the current development of antibacterial activities of quinoline analogues, mainly for anti-MRSA activity, and their structure–activity relationships (SARs) from the perspective of using the quinoline nucleus to search for novel potential anti-MRSA candidates. Additionally, the mechanisms of some representative quinoline analogues against MRSA were clarified. Altogether, this review could provide further insights for the rational development of quinoline-based antibacterial drugs, especially against MRSA.
2024, 35(1): 108513
doi: 10.1016/j.cclet.2023.108513
Abstract:
Photothermal effect has been widely employed in the H2 evolution process at the advantage of using clean energy sources to produce another one of higher benefits. The solar-to-heat conversion have various forms and heat can facilitate reactions in a variety of dimensions. Hence, summarizing the sources and destinations of heat is important for constructing hydrogen production systems of higher efficiency. This view mainly focuses on the recent state-of-art progress of hydrogen evolution reaction (HER) based on photothermal effect. First, we introduce the main pathways of photothermal conversions applied in H2 evolution. Then, the functions of the photothermal effect are clearly summarized. Furthermore, we go beyond the catalytic reaction and introduce a method to improve the catalytic system by changing the catalytic bulk phase through thermal means. In the end, we sort out the challenges and outlook to offer some noble insights for this promising area.
Photothermal effect has been widely employed in the H2 evolution process at the advantage of using clean energy sources to produce another one of higher benefits. The solar-to-heat conversion have various forms and heat can facilitate reactions in a variety of dimensions. Hence, summarizing the sources and destinations of heat is important for constructing hydrogen production systems of higher efficiency. This view mainly focuses on the recent state-of-art progress of hydrogen evolution reaction (HER) based on photothermal effect. First, we introduce the main pathways of photothermal conversions applied in H2 evolution. Then, the functions of the photothermal effect are clearly summarized. Furthermore, we go beyond the catalytic reaction and introduce a method to improve the catalytic system by changing the catalytic bulk phase through thermal means. In the end, we sort out the challenges and outlook to offer some noble insights for this promising area.
2024, 35(1): 108669
doi: 10.1016/j.cclet.2023.108669
Abstract:
The rapid and precise fabrication of multiscale supramolecular assemblies using micro/nanofluidic techniques has emerged as a dynamic area of research in supramolecular chemistry, materials chemistry, and organic chemistry. This review summarizes the application of micro/nanofluidic techniques in constructing supramolecular assemblies, including nanoscale supramolecular assemblies such as macrocycles and cages, microscale supramolecular assemblies such as metal organic frameworks (MOFs) and covalent organic frameworks (COFs), and macroscale supramolecular assemblies such as supramolecular hydrogels. Compared to conventional synthesis methods, micro/nanofluidic techniques for the production of supramolecular assemblies have significant advantages, including enhanced safety, high reaction rates, improved selectivity/yield, and scalability. Additionally, micro/nanofluidic systems facilitate the creation of precisely controllable micro/nanoconfined environments, allowing for a unique flow behavior that improves our understanding of the supramolecular self-assembly process. Such systems may also lead to the development of novel supramolecular assemblies that differ from those generated via traditional methods.
The rapid and precise fabrication of multiscale supramolecular assemblies using micro/nanofluidic techniques has emerged as a dynamic area of research in supramolecular chemistry, materials chemistry, and organic chemistry. This review summarizes the application of micro/nanofluidic techniques in constructing supramolecular assemblies, including nanoscale supramolecular assemblies such as macrocycles and cages, microscale supramolecular assemblies such as metal organic frameworks (MOFs) and covalent organic frameworks (COFs), and macroscale supramolecular assemblies such as supramolecular hydrogels. Compared to conventional synthesis methods, micro/nanofluidic techniques for the production of supramolecular assemblies have significant advantages, including enhanced safety, high reaction rates, improved selectivity/yield, and scalability. Additionally, micro/nanofluidic systems facilitate the creation of precisely controllable micro/nanoconfined environments, allowing for a unique flow behavior that improves our understanding of the supramolecular self-assembly process. Such systems may also lead to the development of novel supramolecular assemblies that differ from those generated via traditional methods.
2024, 35(1): 108714
doi: 10.1016/j.cclet.2023.108714
Abstract:
Hospital sewage contains various harmful pharmaceutical contaminants (e.g., antibiotics, anti-inflammatory agents, and painkillers) and pathogens (e.g., bacteria, viruses, and parasites), whose direct discharge into the environment will induce diseases and pose a powerful threat to human health and safety, and environmental ecology. In recent years, advanced oxidation processes (AOPs), particularly photocatalysis, electrocatalysis, and ozone catalysis have been developed as widespread and effective techniques for hospital sewage treatments. However, there is a lack of systematic comparison and review of the prior studies on hospital sewage treatment using AOPs systems. This review elaborates on the mechanisms, removal efficiencies, and advantages/disadvantages of these AOPs systems for hospital wastewater decontamination and disinfection. Meanwhile, some novel and potential technologies such as photo-electrocatalysis, electro-peroxone, Fenton/Fenton-like, and piezoelectric catalysis are also included and summarized. Moreover, we further summarize and compare the capacity of these AOPs to treat the actual hospital wastewater under the impact of the water matrix and pH, and estimate the economic cost of these technologies for practical application. Finally, the future development directions of AOPs for hospital wastewater decontamination and disinfection have been prospected. Overall, this study provides a comparison and overview of these AOP systems in an attempt to raise extensive concerns about hospital wastewater decontamination and disinfection technologies and guide researchers to discover the future directions of technologies optimization, which would be a crucial step forward in the field of hospital sewage treatment.
Hospital sewage contains various harmful pharmaceutical contaminants (e.g., antibiotics, anti-inflammatory agents, and painkillers) and pathogens (e.g., bacteria, viruses, and parasites), whose direct discharge into the environment will induce diseases and pose a powerful threat to human health and safety, and environmental ecology. In recent years, advanced oxidation processes (AOPs), particularly photocatalysis, electrocatalysis, and ozone catalysis have been developed as widespread and effective techniques for hospital sewage treatments. However, there is a lack of systematic comparison and review of the prior studies on hospital sewage treatment using AOPs systems. This review elaborates on the mechanisms, removal efficiencies, and advantages/disadvantages of these AOPs systems for hospital wastewater decontamination and disinfection. Meanwhile, some novel and potential technologies such as photo-electrocatalysis, electro-peroxone, Fenton/Fenton-like, and piezoelectric catalysis are also included and summarized. Moreover, we further summarize and compare the capacity of these AOPs to treat the actual hospital wastewater under the impact of the water matrix and pH, and estimate the economic cost of these technologies for practical application. Finally, the future development directions of AOPs for hospital wastewater decontamination and disinfection have been prospected. Overall, this study provides a comparison and overview of these AOP systems in an attempt to raise extensive concerns about hospital wastewater decontamination and disinfection technologies and guide researchers to discover the future directions of technologies optimization, which would be a crucial step forward in the field of hospital sewage treatment.
2024, 35(1): 108740
doi: 10.1016/j.cclet.2023.108740
Abstract:
Pillar[n]arenes are a novel class of macrocyclic hosts reported by Ogoshi and co-workers in 2008. Because of their rigid pillar structures, interesting host–guest properties and ease of modifications, pillar[n]arenes have been developed rapidly in the field of functional materials and biomedicine. The modifications of pillar[n]arenes at different positions can give them varied characteristics. Functional groups can be introduced into one position of pillar[n]arenes without changing host–guest properties of pillar[n]arenes. A series of pillar[n]arene dimers, trimers, tetramers and metallacycles can be constructed by mono-functionalized pillar[n]arenes. In this review, two synthetic methods of mono-functionalized pillar[n]arenes are summarized and structures containing mono-functionalized pillar[n]arenes are described. Furthermore, the applications of mono-functionalized pillar[n]arenes in different fields (e.g., supramolecular polymers, sensors, molecular machines, catalysis, biological applications and light-harvesting systems) are also introduced. Hopefully, this article will be useful for researchers studying pillar[n]arenes, especially the mono-functionalized pillar[n]arenes.
Pillar[n]arenes are a novel class of macrocyclic hosts reported by Ogoshi and co-workers in 2008. Because of their rigid pillar structures, interesting host–guest properties and ease of modifications, pillar[n]arenes have been developed rapidly in the field of functional materials and biomedicine. The modifications of pillar[n]arenes at different positions can give them varied characteristics. Functional groups can be introduced into one position of pillar[n]arenes without changing host–guest properties of pillar[n]arenes. A series of pillar[n]arene dimers, trimers, tetramers and metallacycles can be constructed by mono-functionalized pillar[n]arenes. In this review, two synthetic methods of mono-functionalized pillar[n]arenes are summarized and structures containing mono-functionalized pillar[n]arenes are described. Furthermore, the applications of mono-functionalized pillar[n]arenes in different fields (e.g., supramolecular polymers, sensors, molecular machines, catalysis, biological applications and light-harvesting systems) are also introduced. Hopefully, this article will be useful for researchers studying pillar[n]arenes, especially the mono-functionalized pillar[n]arenes.
2024, 35(1): 108829
doi: 10.1016/j.cclet.2023.108829
Abstract:
Sequential energy transfer is ubiquitous in natural light-harvesting systems (LHSs), which greatly promotes the exploitation of light energy. The LHSs in nature are sophisticated supramolecular assemblies of chlorophyll molecules that carry out efficient light harvesting through cascade energy transfer process. Inspired by nature, scientists have paid much attention to fabricate stepwise LHSs based on assorted supramolecular scaffolds in recent years. Light-harvesting antennas and energy acceptors can be accommodated in particular scaffolds, which offer great convenience for energy transfer between them. These systems not only further mimic photosynthesis, but also demonstrate many potential applications, such as photocatalysis, tunable luminescence, and information encryption, etc. In this review article, aiming at offering a practical guide to this emerging research field, the introduction of construction strategies towards sequential LHSs will be presented. Different scaffolds are classified and highlighted, including host-guest assemblies, metal-coordination assemblies, as well as bio-macromolecular and other supramolecular scaffolds.
Sequential energy transfer is ubiquitous in natural light-harvesting systems (LHSs), which greatly promotes the exploitation of light energy. The LHSs in nature are sophisticated supramolecular assemblies of chlorophyll molecules that carry out efficient light harvesting through cascade energy transfer process. Inspired by nature, scientists have paid much attention to fabricate stepwise LHSs based on assorted supramolecular scaffolds in recent years. Light-harvesting antennas and energy acceptors can be accommodated in particular scaffolds, which offer great convenience for energy transfer between them. These systems not only further mimic photosynthesis, but also demonstrate many potential applications, such as photocatalysis, tunable luminescence, and information encryption, etc. In this review article, aiming at offering a practical guide to this emerging research field, the introduction of construction strategies towards sequential LHSs will be presented. Different scaffolds are classified and highlighted, including host-guest assemblies, metal-coordination assemblies, as well as bio-macromolecular and other supramolecular scaffolds.
2024, 35(1): 108860
doi: 10.1016/j.cclet.2023.108860
Abstract:
The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much attention. This minireview introduces the synthesis of a variety of degradable polymers from the (co)polymerizations of several typical oxygenated monomers such as epoxides, cyclic carbonates, cyclic esters, carbon dioxide (CO2), carbonyl sulfide (COS), and cyclic anhydrides. We highlight the catalysts and mechanisms for these (co)polymerizations. The ring-opening copolymerization of five-membered carbonate with cyclic anhydride or COS has been introduced. We also highlight the synthesis of block copolymers and cyclic copolymers with well-defined sequences by the method of growing center switching. We hope that these new polymerization systems can provide new ideas for the development of degradable low-carbon polymers in the future.
The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much attention. This minireview introduces the synthesis of a variety of degradable polymers from the (co)polymerizations of several typical oxygenated monomers such as epoxides, cyclic carbonates, cyclic esters, carbon dioxide (CO2), carbonyl sulfide (COS), and cyclic anhydrides. We highlight the catalysts and mechanisms for these (co)polymerizations. The ring-opening copolymerization of five-membered carbonate with cyclic anhydride or COS has been introduced. We also highlight the synthesis of block copolymers and cyclic copolymers with well-defined sequences by the method of growing center switching. We hope that these new polymerization systems can provide new ideas for the development of degradable low-carbon polymers in the future.
2024, 35(1): 108900
doi: 10.1016/j.cclet.2023.108900
Abstract:
Increasing environmental pollution and shortage of conventional fossil fuels have made it urgent to develop renewable and clean energy sources. Electrocatalytic water splitting, with its abundant raw materials, simple process, and zero carbon emission, is considered one of the most promising processes for producing carbon-neutral hydrogen which has excellent energy conversion efficiency and high gravimetric energy density. Among them, oxygen evolution reaction (OER) electrocatalysts and hydrogen evolution reaction (HER) electrocatalysts are critical to decreasing the intrinsic reaction energy barrier and boosting the hydrogen evolution efficiency. Therefore, it is imperative to develop and design low-cost, highly active, and stable OER and HER electrocatalysts to lower the overpotential and drive the electrocatalytic reactions. Transition metal sulfides, especially iron-based sulfides, have attracted extensive exploration by researchers as a result of its high abundance in the Earth's crust and near-metallic conductivity. Consequently, in this review, we systematically and comprehensively summarize the progress in the application of iron-based sulfides and their composites as OER and HER electrocatalysts in electrocatalysis. Detailed descriptions and illustrations of the special relationships among their composition, structure, and electrocatalytic performance are presented. Finally, this review points out the challenges and future prospects of iron-based sulfides in practical applications for designing and fabricating more promising iron-based sulfide OER and HER electrocatalysts. We believe that iron-based sulfide materials will have a wide range of application prospects as OER and HER electrocatalysts in the future.
Increasing environmental pollution and shortage of conventional fossil fuels have made it urgent to develop renewable and clean energy sources. Electrocatalytic water splitting, with its abundant raw materials, simple process, and zero carbon emission, is considered one of the most promising processes for producing carbon-neutral hydrogen which has excellent energy conversion efficiency and high gravimetric energy density. Among them, oxygen evolution reaction (OER) electrocatalysts and hydrogen evolution reaction (HER) electrocatalysts are critical to decreasing the intrinsic reaction energy barrier and boosting the hydrogen evolution efficiency. Therefore, it is imperative to develop and design low-cost, highly active, and stable OER and HER electrocatalysts to lower the overpotential and drive the electrocatalytic reactions. Transition metal sulfides, especially iron-based sulfides, have attracted extensive exploration by researchers as a result of its high abundance in the Earth's crust and near-metallic conductivity. Consequently, in this review, we systematically and comprehensively summarize the progress in the application of iron-based sulfides and their composites as OER and HER electrocatalysts in electrocatalysis. Detailed descriptions and illustrations of the special relationships among their composition, structure, and electrocatalytic performance are presented. Finally, this review points out the challenges and future prospects of iron-based sulfides in practical applications for designing and fabricating more promising iron-based sulfide OER and HER electrocatalysts. We believe that iron-based sulfide materials will have a wide range of application prospects as OER and HER electrocatalysts in the future.
2024, 35(1): 109014
doi: 10.1016/j.cclet.2023.109014
Abstract:
Molecular doping has become a widely used method to modulate the electric performance of organic semiconductors (OSC). Highly effective charge transfer during molecular doping is desired to achieve ideal electrical conductivity. Two types of charge transfer mechanisms are widely accepted in molecular doping process: integer charge transfer (ICT) and charge transfer complex (CTC). In this review, fundamental principles of two mechanisms are revisited and the characterization methods are depicted. The key points for the formation of two mechanisms are highlighted from aspects of molecular structure and process engineering. Then, the strategies to improve the proportion of ICT are discussed. Finally, the challenges and perspectives for future developments in the molecular doping of polymer semiconductors are provided.
Molecular doping has become a widely used method to modulate the electric performance of organic semiconductors (OSC). Highly effective charge transfer during molecular doping is desired to achieve ideal electrical conductivity. Two types of charge transfer mechanisms are widely accepted in molecular doping process: integer charge transfer (ICT) and charge transfer complex (CTC). In this review, fundamental principles of two mechanisms are revisited and the characterization methods are depicted. The key points for the formation of two mechanisms are highlighted from aspects of molecular structure and process engineering. Then, the strategies to improve the proportion of ICT are discussed. Finally, the challenges and perspectives for future developments in the molecular doping of polymer semiconductors are provided.
2024, 35(1): 108883
doi: 10.1016/j.cclet.2023.108883
Abstract:
