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2022 Volume 50 Issue 6
2022, 50(6): 819-829,858
doi: 10.19756/j.issn.0253-3820.221013
Abstract:
The collection and analysis of biological samples is the effective method for disease diagnosis and treatment. Blood sampling and analysis are standard methods in clinical diagnosis, but they are commonly invasive and usually cause tissue damage and patient discomfort. Interstitial fluid(ISF) is a promising alternative candidate of blood owing to the rich biological information; however,it is still great challenge to minimally and non-invasively sample sufficient targets in skin ISF. In recent years, microneedles(MNs) have received considerable attention in ISF research due to their high efficiency, safety, convenience and painless characteristics. As the micron-level needle array, MNs have achieved remarkable results in medical cosmetology, molecular delivery, diagnostic monitoring and disease treatment, but little attention has been paid to the application of MNs for bioanalysis in ISF. This review summarizes the materials of microneedle, and details the application of MNs in ISF sampling,biomarker capture and analysis, and wearable sensing, while exploring the development prospects of MNs as an emerging research field and summarizing the challenges to be considered and existing in the transformation of technological achievements.
The collection and analysis of biological samples is the effective method for disease diagnosis and treatment. Blood sampling and analysis are standard methods in clinical diagnosis, but they are commonly invasive and usually cause tissue damage and patient discomfort. Interstitial fluid(ISF) is a promising alternative candidate of blood owing to the rich biological information; however,it is still great challenge to minimally and non-invasively sample sufficient targets in skin ISF. In recent years, microneedles(MNs) have received considerable attention in ISF research due to their high efficiency, safety, convenience and painless characteristics. As the micron-level needle array, MNs have achieved remarkable results in medical cosmetology, molecular delivery, diagnostic monitoring and disease treatment, but little attention has been paid to the application of MNs for bioanalysis in ISF. This review summarizes the materials of microneedle, and details the application of MNs in ISF sampling,biomarker capture and analysis, and wearable sensing, while exploring the development prospects of MNs as an emerging research field and summarizing the challenges to be considered and existing in the transformation of technological achievements.
2022, 50(6): 830-838
doi: 10.19756/j.issn.0253-3820.210852
Abstract:
Heavy metal ions(HMIs) are toxic and non-degradable, possessing a serious threat to the ecological environment, biodiversity and human health. Electrochemical method is an effective method for treating HMIs wastewater, and electrode materials are the critical components in the removal of HMIs. This work reviewed the mechanism of HMIs in the process of electrochemistry, such as electrosorption, electro-oxidation, electro-reduction, and electrodeposition. In addition, the effect of electrode materials on the removal of HMIs was also discussed, including removal efficiency, removal mechanism and current efficiency. At last, the development trends of electrochemical methods and electrode materials were prospected according to the advantages and bottlenecks of HMIs removal.
Heavy metal ions(HMIs) are toxic and non-degradable, possessing a serious threat to the ecological environment, biodiversity and human health. Electrochemical method is an effective method for treating HMIs wastewater, and electrode materials are the critical components in the removal of HMIs. This work reviewed the mechanism of HMIs in the process of electrochemistry, such as electrosorption, electro-oxidation, electro-reduction, and electrodeposition. In addition, the effect of electrode materials on the removal of HMIs was also discussed, including removal efficiency, removal mechanism and current efficiency. At last, the development trends of electrochemical methods and electrode materials were prospected according to the advantages and bottlenecks of HMIs removal.
2022, 50(6): 839-849
doi: 10.19756/j.issn.0253-3820.210833
Abstract:
Modern spectral technology has developed rapidly, which can directly carry out rapid and nondestructive analysis of liquids and solids. Different types of spectra have different analysis emphases. To achieve more comprehensive and accurate analysis, it needs to be combined with a variety of analysis methods. Multispectral data fusion technology is to optimize and integrate different types of spectra to realize the complementary advantages of single spectrum, so as to obtain more comprehensive, more reliable and richer characteristic data and improve the accuracy and stability of model prediction. This paper introduces the fusion strategies of low, medium and high levels data fusion by fusion structure, respectively, evaluates the advantages and disadvantages of each fusion strategy,summarizes the new strategies and methods of multispectral data fusion technology in recent years, and focuses on the research and application progress of this technology, The fusion strategies and methods of different spectral technologies in different fields are listed in this paper, and the application prospects of multispectral data fusion technology are discussed.
Modern spectral technology has developed rapidly, which can directly carry out rapid and nondestructive analysis of liquids and solids. Different types of spectra have different analysis emphases. To achieve more comprehensive and accurate analysis, it needs to be combined with a variety of analysis methods. Multispectral data fusion technology is to optimize and integrate different types of spectra to realize the complementary advantages of single spectrum, so as to obtain more comprehensive, more reliable and richer characteristic data and improve the accuracy and stability of model prediction. This paper introduces the fusion strategies of low, medium and high levels data fusion by fusion structure, respectively, evaluates the advantages and disadvantages of each fusion strategy,summarizes the new strategies and methods of multispectral data fusion technology in recent years, and focuses on the research and application progress of this technology, The fusion strategies and methods of different spectral technologies in different fields are listed in this paper, and the application prospects of multispectral data fusion technology are discussed.
2022, 50(6): 850-858
doi: 10.19756/j.issn.0253-3820.221111
Abstract:
The development of many diseases(e.g., atherosclerosis) is closely associated with abnormal level of low density lipoprotein(LDL), and developing methods for rapid and sensitive detection of LDL is of great importance to early diagnosis of atherosclerosis. In this work, a novel electrochemical sensor based on DNA origami-based enzymatic cascade catalysis was reported for detection of LDL. Benefiting from the programmability and addressability of nucleic acids, two enzymes(i.e., cholesterol oxidase and horseradish peroxidase) were specifically assembled on DNA origami, and the cascade catalysis efficiency towards LDL was optimized by regulating their distance, including 20, 40 and 80 nm. Through Au-S chemical bond, DNA origami loading enzymes was modified on Au electrode to construct enzymatic cascade catalysis-based electrochemical sensor. The results demonstrated that this sensor showed excellent performance for LDL detection, with a linear response range of 2-15 μmol/L, a low limit of detection of 1.8 μmol/L(S/N=3), and good selectivity. The recoveries of LDL spiked in healthy human serum sample were 97.8%-103.6%, indicating good reproducibility and stability. This electrochemical sensor utilizing DNA origami-based enzymatic cascade catalysis provided a promising tool for rapid and sensitive detection of LDL, holding a great potential for early diagnosis of atherosclerosis.
The development of many diseases(e.g., atherosclerosis) is closely associated with abnormal level of low density lipoprotein(LDL), and developing methods for rapid and sensitive detection of LDL is of great importance to early diagnosis of atherosclerosis. In this work, a novel electrochemical sensor based on DNA origami-based enzymatic cascade catalysis was reported for detection of LDL. Benefiting from the programmability and addressability of nucleic acids, two enzymes(i.e., cholesterol oxidase and horseradish peroxidase) were specifically assembled on DNA origami, and the cascade catalysis efficiency towards LDL was optimized by regulating their distance, including 20, 40 and 80 nm. Through Au-S chemical bond, DNA origami loading enzymes was modified on Au electrode to construct enzymatic cascade catalysis-based electrochemical sensor. The results demonstrated that this sensor showed excellent performance for LDL detection, with a linear response range of 2-15 μmol/L, a low limit of detection of 1.8 μmol/L(S/N=3), and good selectivity. The recoveries of LDL spiked in healthy human serum sample were 97.8%-103.6%, indicating good reproducibility and stability. This electrochemical sensor utilizing DNA origami-based enzymatic cascade catalysis provided a promising tool for rapid and sensitive detection of LDL, holding a great potential for early diagnosis of atherosclerosis.
2022, 50(6): 859-868
doi: 10.19756/j.issn.0253-3820.221091
Abstract:
Conducting polymers-based hydrogels, especially poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), have received increasing attention in the fields of bioelectronics and biosensors. However, current preparation methods of PEDOT:PSS hydrogel mostly use non-conductive hydrogel as a pre-template or severe treatment condition, which greatly limits the electrochemical biosensing application of hydrogels. Herein, we report a novel method for preparing PEDOT:PSS hydrogel. The PEDOT:PSS aqueous solution containing ethylene glycol is treated by vacuum drying,then the stable PEDOT:PSS hydrogel with three-dimensional cross-linking network is obtained by swelling. The prepared PEDOT:PSS hydrogel with micro/nano hierarchical pores and three-dimensional conductive network structure, has high conductivity(3321.33 ±129.41 S/m) and high stability in 2 months.The hydrogel-modified electrode not only has good property of heterogeneous electron transfer and mass transfer ability, but also can effectively resist non-specific adsorption of protein more than 1 month.The PEDOT:PSS hydrogel can stably entrap enzyme and maintain its activity, and the initial signal of the enzyme can be maintained more than 90% after 1 month. Therefore, the hydrogel provides a new strategy for constructing electrochemical sensors to detect interested substances in complex biological samples.
Conducting polymers-based hydrogels, especially poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), have received increasing attention in the fields of bioelectronics and biosensors. However, current preparation methods of PEDOT:PSS hydrogel mostly use non-conductive hydrogel as a pre-template or severe treatment condition, which greatly limits the electrochemical biosensing application of hydrogels. Herein, we report a novel method for preparing PEDOT:PSS hydrogel. The PEDOT:PSS aqueous solution containing ethylene glycol is treated by vacuum drying,then the stable PEDOT:PSS hydrogel with three-dimensional cross-linking network is obtained by swelling. The prepared PEDOT:PSS hydrogel with micro/nano hierarchical pores and three-dimensional conductive network structure, has high conductivity(3321.33 ±129.41 S/m) and high stability in 2 months.The hydrogel-modified electrode not only has good property of heterogeneous electron transfer and mass transfer ability, but also can effectively resist non-specific adsorption of protein more than 1 month.The PEDOT:PSS hydrogel can stably entrap enzyme and maintain its activity, and the initial signal of the enzyme can be maintained more than 90% after 1 month. Therefore, the hydrogel provides a new strategy for constructing electrochemical sensors to detect interested substances in complex biological samples.
2022, 50(6): 869-877
doi: 10.19756/j.issn.0253-3820.221083
Abstract:
Excessive nitrite in food and water can cause many hazards to human health and the environment, therefore, it is very important to develop reliable, convenient and low-cost methods for nitrite detection. In this study, o-phenylenediamine(OPD) was used as a probe to develop a convenient ratiometric electrochemical method to realize high-performance detection of nitrite on bare screen-printed electrodes. The OPD probe could produce an oxidation signal at a low potential, and nitrite could produce another oxidation signal at a high potential. When OPD coexisted with nitrite, a diazotization reaction occurred in the acidic environment. With the increase of nitrite, free OPD decreased due to reaction consumption, resulting in the decreasing oxidation signal of the probe, while the oxidation signal of nitrite was gradually increased. Based on this principle, ratiometric electrochemical measurement of nitrite was achieved with a linear range of 10-300 μmol/L and a detection limit of 4.7 μmol/L. Accurate determination of the target in environmental water and pickle water samples was also demonstrated. The ratiometric electrochemical method with excellent sensitivity and accuracy, strong anti-interference ability, simple operation and low cost showed broad application prospects.
Excessive nitrite in food and water can cause many hazards to human health and the environment, therefore, it is very important to develop reliable, convenient and low-cost methods for nitrite detection. In this study, o-phenylenediamine(OPD) was used as a probe to develop a convenient ratiometric electrochemical method to realize high-performance detection of nitrite on bare screen-printed electrodes. The OPD probe could produce an oxidation signal at a low potential, and nitrite could produce another oxidation signal at a high potential. When OPD coexisted with nitrite, a diazotization reaction occurred in the acidic environment. With the increase of nitrite, free OPD decreased due to reaction consumption, resulting in the decreasing oxidation signal of the probe, while the oxidation signal of nitrite was gradually increased. Based on this principle, ratiometric electrochemical measurement of nitrite was achieved with a linear range of 10-300 μmol/L and a detection limit of 4.7 μmol/L. Accurate determination of the target in environmental water and pickle water samples was also demonstrated. The ratiometric electrochemical method with excellent sensitivity and accuracy, strong anti-interference ability, simple operation and low cost showed broad application prospects.
2022, 50(6): 878-888
doi: 10.19756/j.issn.0253-3820.221015
Abstract:
Organic electrochemical transistors(OECTs) are widely used in biosensing due to their good biocompatibility, low operating voltage, and excellent signal amplification ability. Functionalization of the gate electrode is crucial for OECTs-based biosensing. However, the existing theory cannot describe the influences of polarization and charge adsorption on the current-voltage(I-V) characteristics. In this work, the Bernards-Malliaras I-V characteristic is modified by constructing the series model of differential capacitance formed at gate/electrolyte and semiconductor-channel/electrolyte interfaces. The effectiveness of the modified model is discussed by experimental investigations, including changing the potentiostatic electrodeposition time, regulating the thickness of poly(3,4-ethylenedioxythio-phene):poly(styrenesulfonate) (PEDOT:PSS) film formed on the surface of the gate-electrode(0.80-3.73 μm) and the gate-electrode/electrolyte interface capacitance(CG) (24.01-120.10 μF). Experimental results show that the transconductance peak increases with the CG increments; when the gate electrode voltage(VG) is set as +0.6 V, the current flowing in the semiconductor channel current(IDS,l) increases monotonically with the CG increments; When VG is set as-0.6 V, IDS,l decreases monotonically with the CG increments. In addition, the aptamer probes anchored on the gate-electrode react specifically with different concentrations of adenosine triphosphate(10-12-10-5 mol/L).Experimental results show that IDS,l decreases with the increments of the adenosine triphosphate concentration,and thus, the amount of adsorbed charge. The qualitative theoretical analyses are consistent with the experimental results. The modified theoretical model proposed herein is expected to provide theoretical support for designing of OECTs and OECTs based biosensors.
Organic electrochemical transistors(OECTs) are widely used in biosensing due to their good biocompatibility, low operating voltage, and excellent signal amplification ability. Functionalization of the gate electrode is crucial for OECTs-based biosensing. However, the existing theory cannot describe the influences of polarization and charge adsorption on the current-voltage(I-V) characteristics. In this work, the Bernards-Malliaras I-V characteristic is modified by constructing the series model of differential capacitance formed at gate/electrolyte and semiconductor-channel/electrolyte interfaces. The effectiveness of the modified model is discussed by experimental investigations, including changing the potentiostatic electrodeposition time, regulating the thickness of poly(3,4-ethylenedioxythio-phene):poly(styrenesulfonate) (PEDOT:PSS) film formed on the surface of the gate-electrode(0.80-3.73 μm) and the gate-electrode/electrolyte interface capacitance(CG) (24.01-120.10 μF). Experimental results show that the transconductance peak increases with the CG increments; when the gate electrode voltage(VG) is set as +0.6 V, the current flowing in the semiconductor channel current(IDS,l) increases monotonically with the CG increments; When VG is set as-0.6 V, IDS,l decreases monotonically with the CG increments. In addition, the aptamer probes anchored on the gate-electrode react specifically with different concentrations of adenosine triphosphate(10-12-10-5 mol/L).Experimental results show that IDS,l decreases with the increments of the adenosine triphosphate concentration,and thus, the amount of adsorbed charge. The qualitative theoretical analyses are consistent with the experimental results. The modified theoretical model proposed herein is expected to provide theoretical support for designing of OECTs and OECTs based biosensors.
2022, 50(6): 889-898
doi: 10.19756/j.issn.0253-3820.221039
Abstract:
Phosphorus is an important indicator in surface water quality standards. Excessive phosphate can lead to eutrophication, so it is necessary to develop an accurate and sensitive method for detection of phosphate in water. In this work, an electrochemical sensor based on boron-doped diamond electrode was developed to achieve sensitive detection of phosphate in water through electrochemical reduction of phosphomolybdate. The sensor achieved excellent performances in detection of phosphate, including wide detection range, high sensitivities(0.301 nA·L/μmol in the range of 0.4-5.0 μmol/L, and 97 nA·L/μmol in the range of 5.0-80.0 μmol/L), and low limit of detection(0.1 μmol/L). Meanwhile, the electrochemical sensor showed good anti-interference ability for phosphate detection, and the recoveries of phosphate in tap and lake water sample were 93.8%-104.5%. Compared with standard spectrophotometry, the electrochemical detection process was environmentally friendly with less usage of reagents. The sensor displayed excellent catalytic properties for detection of phosphate without electrode modification, and had potential for long-term online monitoring of phosphate.
Phosphorus is an important indicator in surface water quality standards. Excessive phosphate can lead to eutrophication, so it is necessary to develop an accurate and sensitive method for detection of phosphate in water. In this work, an electrochemical sensor based on boron-doped diamond electrode was developed to achieve sensitive detection of phosphate in water through electrochemical reduction of phosphomolybdate. The sensor achieved excellent performances in detection of phosphate, including wide detection range, high sensitivities(0.301 nA·L/μmol in the range of 0.4-5.0 μmol/L, and 97 nA·L/μmol in the range of 5.0-80.0 μmol/L), and low limit of detection(0.1 μmol/L). Meanwhile, the electrochemical sensor showed good anti-interference ability for phosphate detection, and the recoveries of phosphate in tap and lake water sample were 93.8%-104.5%. Compared with standard spectrophotometry, the electrochemical detection process was environmentally friendly with less usage of reagents. The sensor displayed excellent catalytic properties for detection of phosphate without electrode modification, and had potential for long-term online monitoring of phosphate.
2022, 50(6): 899-911
doi: 10.19756/j.issn.0253-3820.221048
Abstract:
The hierarchically porous carbon materials were prepared with chitosan(CS) as carbon source, and NaCl, NaOH and Na2CO3 as activators. The morphology, porous structure, specific surface area and pore size distribution of the prepared carbon materials were characterized by scanning electron microscopy, X-ray diffraction, Raman spectrum and nitrogen adsorption-desorption isotherms,respectively. And the electrochemical properties of different carbon materials-modified electrode were studied by electrochemical techniques. Thus, structure-activity relationship between the morphology,structural and physicochemical parameters of different carbon materials and their electrochemical sensing properties were explored. The results showed that the hierarchically porous carbon material(CS-Na2CO3,prepared using Na2CO3 as activator) modified electrode had larger electrochemical active area, faster electron transfer rate and better electrocatalytic performance for three dihydroxybenzene isomers. A highperformance electrochemical sensing platform for simultaneous determination of hydroquinone, catechol and resorcinol was constructed based on the signal enhancement effect of CS-Na2CO3. The linear ranges for simultaneous determination of hydroquinone, catechol and resorcinol were 0.050-1.5 μmol/L,0.050-1.5 μmol/L and 0.50-15 μmol/L, and the detection limits (3σ) were calculated to be 0.012, 0.017 and 0.29 μmol/L, respectively. The prepared sensing platform demonstrated good accuracy in detection of dihydroxybenzene isomers in river water samples.
The hierarchically porous carbon materials were prepared with chitosan(CS) as carbon source, and NaCl, NaOH and Na2CO3 as activators. The morphology, porous structure, specific surface area and pore size distribution of the prepared carbon materials were characterized by scanning electron microscopy, X-ray diffraction, Raman spectrum and nitrogen adsorption-desorption isotherms,respectively. And the electrochemical properties of different carbon materials-modified electrode were studied by electrochemical techniques. Thus, structure-activity relationship between the morphology,structural and physicochemical parameters of different carbon materials and their electrochemical sensing properties were explored. The results showed that the hierarchically porous carbon material(CS-Na2CO3,prepared using Na2CO3 as activator) modified electrode had larger electrochemical active area, faster electron transfer rate and better electrocatalytic performance for three dihydroxybenzene isomers. A highperformance electrochemical sensing platform for simultaneous determination of hydroquinone, catechol and resorcinol was constructed based on the signal enhancement effect of CS-Na2CO3. The linear ranges for simultaneous determination of hydroquinone, catechol and resorcinol were 0.050-1.5 μmol/L,0.050-1.5 μmol/L and 0.50-15 μmol/L, and the detection limits (3σ) were calculated to be 0.012, 0.017 and 0.29 μmol/L, respectively. The prepared sensing platform demonstrated good accuracy in detection of dihydroxybenzene isomers in river water samples.
2022, 50(6): 912-923
doi: 10.19756/j.issn.0253-3820.221115
Abstract:
Donor-acceptor-donor(D-A-D) type fluorescent probes have been widely used in biological imaging due to their excellent optical stability and biocompatibility. By molecular engineering, the fluorescence emission of D-A-D type probe can shift to the near infrared Ⅱ window(NIR-Ⅱ), which shows that the probe has potential for bioimaging and photothermal therapy due to its good photothermal conversion efficiency. However, its large molecular weight leads to unavoidable disadvantages such as poor water solubility, which seriously limits its application. Therefore, in this work, an actively targeted polymer(CRGDK-PEG-b-PLGA) was designed to improve the water-solubility, tumor-specificity and photothermal efficacy of D-A-D type fluorescent probe(TQTCD), thus achieving the integration of diagnosis and treatment. CRGDK-PEG-b-PLGA and TQTCD could self-assemble to form homogeneous and stable nanoparticles(named RPP@TQTCD). This strategy did not affect the fluorescence properties and photothermal effects of TQTCD. CRGDK ligand-modification could increase the tumor accumulation of RPP@TQTCD NPs and interact with the Neuropilin-1(NRP-1) receptor, which was highly expressed on the surface of tumor cells, to promote cellular uptake of RPP@TQTCD NPs through NRP-1-CRGDK pathway.Then, RPP@TQTCD NPs could effectively kill tumor cells under 808 nm laser irradiation in vitro and in vivo. This study provided an effective strategy for the diagnosis and photothermal treatment of triple negative breast cancer(TNBC) through the targeted delivery of hydrophobic probe.
Donor-acceptor-donor(D-A-D) type fluorescent probes have been widely used in biological imaging due to their excellent optical stability and biocompatibility. By molecular engineering, the fluorescence emission of D-A-D type probe can shift to the near infrared Ⅱ window(NIR-Ⅱ), which shows that the probe has potential for bioimaging and photothermal therapy due to its good photothermal conversion efficiency. However, its large molecular weight leads to unavoidable disadvantages such as poor water solubility, which seriously limits its application. Therefore, in this work, an actively targeted polymer(CRGDK-PEG-b-PLGA) was designed to improve the water-solubility, tumor-specificity and photothermal efficacy of D-A-D type fluorescent probe(TQTCD), thus achieving the integration of diagnosis and treatment. CRGDK-PEG-b-PLGA and TQTCD could self-assemble to form homogeneous and stable nanoparticles(named RPP@TQTCD). This strategy did not affect the fluorescence properties and photothermal effects of TQTCD. CRGDK ligand-modification could increase the tumor accumulation of RPP@TQTCD NPs and interact with the Neuropilin-1(NRP-1) receptor, which was highly expressed on the surface of tumor cells, to promote cellular uptake of RPP@TQTCD NPs through NRP-1-CRGDK pathway.Then, RPP@TQTCD NPs could effectively kill tumor cells under 808 nm laser irradiation in vitro and in vivo. This study provided an effective strategy for the diagnosis and photothermal treatment of triple negative breast cancer(TNBC) through the targeted delivery of hydrophobic probe.
2022, 50(6): 924-931
doi: 10.19756/j.issn.0253-3820.221019
Abstract:
High-field asymmetric waveform ion mobility spectrometry(FAIMS) is a fast and sensitive field detection technology, but the detection of polar substances using FAIMS is easily affected by humidity. Based on that nafion tube could selectively and quickly filter water gas, a nafion-FAIMS technology was proposed for rapid detection of environmental hydrogen sulfide(H2S) gas under ambient humidity in this work. The self-made nafion-FAIMS device was used to study the stability of nafionFAIMS in detection of H2S under different humidity conditions, the separation and identification ability of H2S in the presence of typical environmental interferents, the linearity and the detection limit. The results showed that when the relative humidity was 5%-50%, the relative standard deviations(RSDs) of peak position and peak height of H2S spectrum were less than 0.4% and 0.2%, respectively, which were 10 times and 250 times smaller than that of single FAIMS, showing high recognition and quantitative stability. When the dispersion voltage was 1200 V, the relative deviation of peak height and peak position between benzene and H2S mixed gas spectrum and single substance were only 0.7% and 2%, indicating the adaptability of nafion-FAIMS to mixture detection. The signal linearity reached 98% in the H2S concentration range of 0.08-0.46 mg/m3, and the detection limit was 0.04 mg/m3.
High-field asymmetric waveform ion mobility spectrometry(FAIMS) is a fast and sensitive field detection technology, but the detection of polar substances using FAIMS is easily affected by humidity. Based on that nafion tube could selectively and quickly filter water gas, a nafion-FAIMS technology was proposed for rapid detection of environmental hydrogen sulfide(H2S) gas under ambient humidity in this work. The self-made nafion-FAIMS device was used to study the stability of nafionFAIMS in detection of H2S under different humidity conditions, the separation and identification ability of H2S in the presence of typical environmental interferents, the linearity and the detection limit. The results showed that when the relative humidity was 5%-50%, the relative standard deviations(RSDs) of peak position and peak height of H2S spectrum were less than 0.4% and 0.2%, respectively, which were 10 times and 250 times smaller than that of single FAIMS, showing high recognition and quantitative stability. When the dispersion voltage was 1200 V, the relative deviation of peak height and peak position between benzene and H2S mixed gas spectrum and single substance were only 0.7% and 2%, indicating the adaptability of nafion-FAIMS to mixture detection. The signal linearity reached 98% in the H2S concentration range of 0.08-0.46 mg/m3, and the detection limit was 0.04 mg/m3.
2022, 50(6): 932-939
doi: 10.19756/j.issn.0253-3820.210807
Abstract:
Nano metal organic frameworks(NMOFs) have been widely used in biological diagnosis and treatment systems. In this work, a fluorescence analysis method based on gold nanoclusters(AuNCs) and metal organic framework zeolitic imidazolate framework-8(ZIF-8) composite materials was established for high-sensitivity detection of ascorbic acid(AA). The obtained nanocomposite material(AuNCs@ZIF-8) through the confinement effect of MOF(ZIF-8) showed aggregation-induced emission(AIE) enhancement.When AA was combined with ZIF-8, the framework of the composite material was destroyed, and the fluorescence intensity was greatly reduced due to the transition of AuNCs from the aggregate state to the dispersed state. The linear range of AA detection was measured to be 10-100 μmol/L, and the limit of detection(LOD, S/N=3) was 0.3 μmol/L This method could complete the detection of AA within 2 minutes,showing high selectivity for AA detection. This method was used to detect AA in human serum with good results, and the recoveries were 95.7%-100.9%.
Nano metal organic frameworks(NMOFs) have been widely used in biological diagnosis and treatment systems. In this work, a fluorescence analysis method based on gold nanoclusters(AuNCs) and metal organic framework zeolitic imidazolate framework-8(ZIF-8) composite materials was established for high-sensitivity detection of ascorbic acid(AA). The obtained nanocomposite material(AuNCs@ZIF-8) through the confinement effect of MOF(ZIF-8) showed aggregation-induced emission(AIE) enhancement.When AA was combined with ZIF-8, the framework of the composite material was destroyed, and the fluorescence intensity was greatly reduced due to the transition of AuNCs from the aggregate state to the dispersed state. The linear range of AA detection was measured to be 10-100 μmol/L, and the limit of detection(LOD, S/N=3) was 0.3 μmol/L This method could complete the detection of AA within 2 minutes,showing high selectivity for AA detection. This method was used to detect AA in human serum with good results, and the recoveries were 95.7%-100.9%.
2022, 50(6): 940-947
doi: 10.19756/j.issn.0253-3820.221025
Abstract:
Three target peptides, H3K9ac, H3K14ac and H3, in human cell lines were determined by highperformance liquid chromatography coupled with triple quadrupole mass spectrometry under positive ion multiple reaction monitoring mode(MRM). The cell samples were pre-treated by trypsin digestion,propionylation derivatization, desalination, peptide enrichment, and then separated by ACQUITY UPLC BEH C18 column. The results indicated that the three peptides in cells had good linear relationship within the concentration range of 1-250 ng/mL(R2>0.99). The detection limits(S/N=3) of the peptides were 0.1 ng/mL.Accuracy, precision, matrix effects and recoveries meet the methodological requirement for biological samples analysis. The established method had many advantages such as simple operation, high sensitivity,fast detection and accurate quantification, which had been initially applied to evaluate the effects of two classic genotoxic compounds(camptothecin and colchicine) with different modes of action on the acetylation at position 9 and position 14 of histone H3 in cells. This method provided important technical support for DNA damage/repair and transcription research of genotoxic compounds.
Three target peptides, H3K9ac, H3K14ac and H3, in human cell lines were determined by highperformance liquid chromatography coupled with triple quadrupole mass spectrometry under positive ion multiple reaction monitoring mode(MRM). The cell samples were pre-treated by trypsin digestion,propionylation derivatization, desalination, peptide enrichment, and then separated by ACQUITY UPLC BEH C18 column. The results indicated that the three peptides in cells had good linear relationship within the concentration range of 1-250 ng/mL(R2>0.99). The detection limits(S/N=3) of the peptides were 0.1 ng/mL.Accuracy, precision, matrix effects and recoveries meet the methodological requirement for biological samples analysis. The established method had many advantages such as simple operation, high sensitivity,fast detection and accurate quantification, which had been initially applied to evaluate the effects of two classic genotoxic compounds(camptothecin and colchicine) with different modes of action on the acetylation at position 9 and position 14 of histone H3 in cells. This method provided important technical support for DNA damage/repair and transcription research of genotoxic compounds.
2022, 50(6): 948-956
doi: 10.19756/j.issn.0253-3820.221081
Abstract:
A microwave discharge fast flow tube reactor was used to simulate chlorine-initiated oxidation of nopinone(C9H14O). The chemical compositions of radicals and stable products from the oxidation reactions were measured via a home-made vacuum ultraviolet photoionization time of flight mass spectrometer(VUVPI-TOFMS). The kinetic experiments of main radicals and products were also performed. By comparing the results of kinetic experiments and simulation calculations of key species,the reaction pathways of key species in the reaction were further explored. This study showed that the reaction of nopinone with Cl produced radical C9H13O via the hydrogen abstraction pathway. The radical C9H13O reacted with O2 to mainly generate peroxy radical C9H13OO2. Under NOx(NO and NO2) free condition, peroxy radical C9H13OO2 reacted with itself to produce radical C9H13OO, carbonyl compounds C9H12O2 and C9H13OOH. In addition, the peroxy radical C9H13OO2 could also react with HO2 to produce hydroperoxide C9H13OO2H. The mechanism of chlorine-initiated oxidation reactions of nopinone was also revealed through experimental studies and simulation calculations.
A microwave discharge fast flow tube reactor was used to simulate chlorine-initiated oxidation of nopinone(C9H14O). The chemical compositions of radicals and stable products from the oxidation reactions were measured via a home-made vacuum ultraviolet photoionization time of flight mass spectrometer(VUVPI-TOFMS). The kinetic experiments of main radicals and products were also performed. By comparing the results of kinetic experiments and simulation calculations of key species,the reaction pathways of key species in the reaction were further explored. This study showed that the reaction of nopinone with Cl produced radical C9H13O via the hydrogen abstraction pathway. The radical C9H13O reacted with O2 to mainly generate peroxy radical C9H13OO2. Under NOx(NO and NO2) free condition, peroxy radical C9H13OO2 reacted with itself to produce radical C9H13OO, carbonyl compounds C9H12O2 and C9H13OOH. In addition, the peroxy radical C9H13OO2 could also react with HO2 to produce hydroperoxide C9H13OO2H. The mechanism of chlorine-initiated oxidation reactions of nopinone was also revealed through experimental studies and simulation calculations.
2022, 50(6): 957-963
doi: 10.19756/j.issn.0253-3820.210662
Abstract:
An ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) method has been developed for determination of 22 kinds of β-agonists residues in swine, bovine and sheep muscle and liver samples. The animal food samples were extracted with enzymatic probe sonication(EPS) using β-glucuronidase/sulfatase enzymes, followed by clean-up using automatic solid-phase extraction and determination by UPLC-MS/MS. The target analytes were quantified by internal standard methods. Under the optimized EPS conditions, one sample could be exhaustively extracted within 120 s(average recovery 81.2%-100.7%), as compared with 16 h needed for the conventional enzymatic digestion, which was more suitable for high-throughput screening. Furthermore, the clean-up was conducted using automatic solid-phase extraction, and 36 samples could be performed in 30 min simultaneously. The work efficiency was significantly improved, and the relative standard deviations(RSDs) were relatively low(0.3%-7.9%).As compared with the traditional enzymatic digestion and solid-phase extraction techniques, the newly developed method was quick and easy to be performed, which was more suitable for high-throughput detection in routine residual analysis.
An ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) method has been developed for determination of 22 kinds of β-agonists residues in swine, bovine and sheep muscle and liver samples. The animal food samples were extracted with enzymatic probe sonication(EPS) using β-glucuronidase/sulfatase enzymes, followed by clean-up using automatic solid-phase extraction and determination by UPLC-MS/MS. The target analytes were quantified by internal standard methods. Under the optimized EPS conditions, one sample could be exhaustively extracted within 120 s(average recovery 81.2%-100.7%), as compared with 16 h needed for the conventional enzymatic digestion, which was more suitable for high-throughput screening. Furthermore, the clean-up was conducted using automatic solid-phase extraction, and 36 samples could be performed in 30 min simultaneously. The work efficiency was significantly improved, and the relative standard deviations(RSDs) were relatively low(0.3%-7.9%).As compared with the traditional enzymatic digestion and solid-phase extraction techniques, the newly developed method was quick and easy to be performed, which was more suitable for high-throughput detection in routine residual analysis.
2022, 50(6): 964-972
doi: 10.19756/j.issn.0253-3820.210839
Abstract:
As a new class of psychoactive substances, fentanyls have the characteristics of wide variety,rapid replacement and extremely similar structures. The accurate identification of their isomers is a major problem faced by drug analysts. Ultra performance convergence chromatography is a powerful tool to achieve efficient separation of isomers. Therefore, a new method was established for fast separation and detection of fentanyls by ultra performance convergence chromatography-mass spectrometry in this work. The separation conditions of the chromatographic column, modifiers and column temperature were optimized. The separation and detection was conducted on Waters ACQUITY UPC2 BEH column with supercritical fluid CO2 as primary mobile phase, methanol containing 20 mmol/L ammonium formate as the modifier, column temperature at 50℃ and a Xevo TQD triple quadrupole as mass spectrometer. A total of 13 kinds of fentanyls were completely separated within 6.5 min with an above 1.5-resolution to all the isomers. The chromatographic peaks were perfectly symmetric. Methodological statistics showed that, 9 kinds of common drugs did not interfere with the determination of 13 kinds of target substances;the detection limits were 0.01-0.05 ng/mL and the relative standard deviations of the retention time were less than 0.6%. Compared with the conventional ultra-high performance liquid chromatography-mass spectrometry detection method, this method had significant advantages in the separation of isomers,which fully met the anti-drug public security departments' needs for the accurate identification of fentanyls.
As a new class of psychoactive substances, fentanyls have the characteristics of wide variety,rapid replacement and extremely similar structures. The accurate identification of their isomers is a major problem faced by drug analysts. Ultra performance convergence chromatography is a powerful tool to achieve efficient separation of isomers. Therefore, a new method was established for fast separation and detection of fentanyls by ultra performance convergence chromatography-mass spectrometry in this work. The separation conditions of the chromatographic column, modifiers and column temperature were optimized. The separation and detection was conducted on Waters ACQUITY UPC2 BEH column with supercritical fluid CO2 as primary mobile phase, methanol containing 20 mmol/L ammonium formate as the modifier, column temperature at 50℃ and a Xevo TQD triple quadrupole as mass spectrometer. A total of 13 kinds of fentanyls were completely separated within 6.5 min with an above 1.5-resolution to all the isomers. The chromatographic peaks were perfectly symmetric. Methodological statistics showed that, 9 kinds of common drugs did not interfere with the determination of 13 kinds of target substances;the detection limits were 0.01-0.05 ng/mL and the relative standard deviations of the retention time were less than 0.6%. Compared with the conventional ultra-high performance liquid chromatography-mass spectrometry detection method, this method had significant advantages in the separation of isomers,which fully met the anti-drug public security departments' needs for the accurate identification of fentanyls.
