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2022 Volume 50 Issue 1
2022, 50(1): 1-11
doi: 10.19756/j.issn.0253-3820.201488
Abstract:
Lateral flow immunochromatographic strip is one of the mainstream rapid detection products in the current market. Smartphones with built-in high-definition cameras have been popular among consumers in recent years. By taking a picture via mobile phones, then analyzing with machine vision image recognition technology, the optical signal of strip developed color could be converted into digital signal based on visible light colorimetric analysis or fluorescence analysis technology. This has become a research hotspot of rapid detection to realize qualitative or quantitative determination based on strip color development in recent years. In this paper, the applications of rapid detection technology based on smartphone and lateral flow immunoassay in medical diagnosis, environmental monitoring and food safety were reviewed. Moreover, the quantitative detection mode, implementation method and challenges of rapid test strip products based on smartphone photography were also discussed and summarized, which could provide reference for its realization of multi-target analysis, on-site rapid qualitative and quantitative detection.
Lateral flow immunochromatographic strip is one of the mainstream rapid detection products in the current market. Smartphones with built-in high-definition cameras have been popular among consumers in recent years. By taking a picture via mobile phones, then analyzing with machine vision image recognition technology, the optical signal of strip developed color could be converted into digital signal based on visible light colorimetric analysis or fluorescence analysis technology. This has become a research hotspot of rapid detection to realize qualitative or quantitative determination based on strip color development in recent years. In this paper, the applications of rapid detection technology based on smartphone and lateral flow immunoassay in medical diagnosis, environmental monitoring and food safety were reviewed. Moreover, the quantitative detection mode, implementation method and challenges of rapid test strip products based on smartphone photography were also discussed and summarized, which could provide reference for its realization of multi-target analysis, on-site rapid qualitative and quantitative detection.
2022, 50(1): 12-24
doi: 10.19756/j.issn.0253-3820.211012
Abstract:
Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) is a soft ionization mass spectrometry technology and widely used in the analysis of various molecules such as proteins, polypeptides, nucleic acids and polymers, etc. However, the application of MALDI-TOF MS on detection of low molecular weight compounds (LMWC) is limited due to the matrix related peak interference and inhomogeneous crystallization of matrix/analyte. In recent years, a variety of novel matrixes have been developed for detection of LMWC. This paper reviews the matrix of MALDI-TOF MS in recent 10 years from three aspects, including new inorganic material matrix, organic compound matrix and other matrix (metal organic framework, ionic liquid matrix, reactive matrix, etc.) The research progress of determination of LMWC by MALDI-TOF MS, and the preparation, characteristics and application of matrix are introduced, and the future development trend is prospected.
Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) is a soft ionization mass spectrometry technology and widely used in the analysis of various molecules such as proteins, polypeptides, nucleic acids and polymers, etc. However, the application of MALDI-TOF MS on detection of low molecular weight compounds (LMWC) is limited due to the matrix related peak interference and inhomogeneous crystallization of matrix/analyte. In recent years, a variety of novel matrixes have been developed for detection of LMWC. This paper reviews the matrix of MALDI-TOF MS in recent 10 years from three aspects, including new inorganic material matrix, organic compound matrix and other matrix (metal organic framework, ionic liquid matrix, reactive matrix, etc.) The research progress of determination of LMWC by MALDI-TOF MS, and the preparation, characteristics and application of matrix are introduced, and the future development trend is prospected.
2022, 50(1): 25-38
doi: 10.19756/j.issn.0253-3820.210530
Abstract:
Digital polymerase chain reaction (PCR), as a nucleic acid detection technology with wide application prospect, has become one of the most accurate nucleic acid detection technology at present. Multiplex detection is an important direction for the development of digital PCR technique. With the development of microfluidic technology, multiplex digital PCR technique has become more and more mature. This paper reviewed the research progresses of multiplex digital PCR in recent years, especially summarized the implementation of multiplex digital PCR technique in the past five years, and introduced the application of multiplex digital PCR technique in hot areas such as liquid biopsy, transgenic detection, and SARS-Cov-2 detection. Finally, the issues and challenges faced by multiplex digital PCR technique were discussed and the future direction of the technology was foreseen.
Digital polymerase chain reaction (PCR), as a nucleic acid detection technology with wide application prospect, has become one of the most accurate nucleic acid detection technology at present. Multiplex detection is an important direction for the development of digital PCR technique. With the development of microfluidic technology, multiplex digital PCR technique has become more and more mature. This paper reviewed the research progresses of multiplex digital PCR in recent years, especially summarized the implementation of multiplex digital PCR technique in the past five years, and introduced the application of multiplex digital PCR technique in hot areas such as liquid biopsy, transgenic detection, and SARS-Cov-2 detection. Finally, the issues and challenges faced by multiplex digital PCR technique were discussed and the future direction of the technology was foreseen.
2022, 50(1): 39-46
doi: 10.19756/j.issn.0253-3820.210483
Abstract:
Tip-enhanced Raman spectroscopy (TERS) is a new analytical technology that combines Raman spectroscopy and scanning probe microscopies (SPM). By enhancing the Raman signal at "hot spots", it is possible to have a deeper understanding of molecular composition and structure, reaction mechanism, and molecular orientation. At present, most of tip-enhanced Raman instruments adopt a split design, which is bulky, expensive and complicated in structure, limiting the popularization of the instrument and the development of related research. In this work, an integrated tip-enhanced Raman spectroscopy instrument was designed and developed, which effectively improved the integration of the instrument, reduced the transmission loss of the optical fiber and reduced the volume and cost of the system. The spectrometer consisted of a laser excitation and Raman collection module, a spectrometer module, and a tip and laser coupled imaging module. The three modules were placed in a closed housing with a volume of 410 mm×305 mm×85 mm. The instrument was optically calibrated using a standard Ne-Ar light source. The resolution of the instrument was 0.56 nm, and the spectral detection range was 640-770 nm. For the Ne-Ar calibration light source, the observed profile was Gaussian lineshape, and the contour of the ν(A1) vibration peak of carbon tetrachloride was a combination of 51% Gaussian and 49% Lorentzian lines. Finally, the tip-enhanced Raman spectrum of 4'-(pyridine-4-yl)-biphenyl-4-yl) methanethiol (4-PBT) molecules was successfully obtained using this spectrometer, which verified the feasibility of the integrated spectrometer and provided technical accumulation for the promotion of tip Raman spectroscopy technology.
Tip-enhanced Raman spectroscopy (TERS) is a new analytical technology that combines Raman spectroscopy and scanning probe microscopies (SPM). By enhancing the Raman signal at "hot spots", it is possible to have a deeper understanding of molecular composition and structure, reaction mechanism, and molecular orientation. At present, most of tip-enhanced Raman instruments adopt a split design, which is bulky, expensive and complicated in structure, limiting the popularization of the instrument and the development of related research. In this work, an integrated tip-enhanced Raman spectroscopy instrument was designed and developed, which effectively improved the integration of the instrument, reduced the transmission loss of the optical fiber and reduced the volume and cost of the system. The spectrometer consisted of a laser excitation and Raman collection module, a spectrometer module, and a tip and laser coupled imaging module. The three modules were placed in a closed housing with a volume of 410 mm×305 mm×85 mm. The instrument was optically calibrated using a standard Ne-Ar light source. The resolution of the instrument was 0.56 nm, and the spectral detection range was 640-770 nm. For the Ne-Ar calibration light source, the observed profile was Gaussian lineshape, and the contour of the ν(A1) vibration peak of carbon tetrachloride was a combination of 51% Gaussian and 49% Lorentzian lines. Finally, the tip-enhanced Raman spectrum of 4'-(pyridine-4-yl)-biphenyl-4-yl) methanethiol (4-PBT) molecules was successfully obtained using this spectrometer, which verified the feasibility of the integrated spectrometer and provided technical accumulation for the promotion of tip Raman spectroscopy technology.
2022, 50(1): 47-53
doi: 10.19756/j.issn.0253-3820.211101
Abstract:
Carbon quantum dots-based mesoporous mesoporous silica nanomaterials (CD-MSN) was designed and prepared for detection and adsorption of Cu2+. The fluorescence of CD-MSN could be selectively quenched by Cu2+, therefore, a fluorescence method was established for detection of Cu2+. A linear response range was found in the Cu2+ concentration range from 1.0 to 10.0 μmol/L, with limit of detection (LOD, S/N=3) of 0.22 μmol/L. Meanwhile, the maximal adsorption capacity of CD-MSN for Cu2+ was determined as 5.71 mg/g by inductively coupled plasma optical emission spectrometry (ICP-OES). In addition, the CD-MSN was successfully applied to detect Cu2+ in real tap water samples. The results suggested that the synthesized CD-MSN had the potential in detection of Cu2+ in real water samples.
Carbon quantum dots-based mesoporous mesoporous silica nanomaterials (CD-MSN) was designed and prepared for detection and adsorption of Cu2+. The fluorescence of CD-MSN could be selectively quenched by Cu2+, therefore, a fluorescence method was established for detection of Cu2+. A linear response range was found in the Cu2+ concentration range from 1.0 to 10.0 μmol/L, with limit of detection (LOD, S/N=3) of 0.22 μmol/L. Meanwhile, the maximal adsorption capacity of CD-MSN for Cu2+ was determined as 5.71 mg/g by inductively coupled plasma optical emission spectrometry (ICP-OES). In addition, the CD-MSN was successfully applied to detect Cu2+ in real tap water samples. The results suggested that the synthesized CD-MSN had the potential in detection of Cu2+ in real water samples.
2022, 50(1): 54-63
doi: 10.19756/j.issn.0253-3820.210812
Abstract:
Manganese (Mn) single atom nanozyme with peroxidase-like activity was synthesized through a solvothermal method and used for the detection of alkaline phosphatase (ALP) activity. By using formamide as the carbon and nitrogen source and MnCl2 as the Mn source, formamide converted Mn and nitroren co-doped carbon (f-MnNC) could be obtained after reacting at 180℃ for 12 h. The structure and morphology were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffractometer, etc., and the peroxidase-like activity was investigated mainly using UV-visible absorption spectroscopy. In the presence of H2O2, f-MnNC could catalyze the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue oxidized TMB (oxTMB), with a characteristic absorption peak centered at 652 nm. ALP could catalyze the hydrolysis of L-ascorbic acid-2-phosphate (AA2P) to produce ascorbic acid (AA), which then reduced oxTMB to TMB, resulting in faded color and decreased absorbance. The degree of colorimetric signal change was related to ALP activity, and thus ALP activity could be quantitatively detected by employing AA2P as the substrate. In the activity range of 0.1-10 mU/mL, there was a good linear relationship between the absorbance at 652 nm and the ALP activity, and the detection limit (S/N=3) was 0.059 mU/mL. Other proteins and enzymes had no obvious interference with ALP detection, indicating good selectivity for ALP activity detection. The method was successfully applied to the determination of ALP activity in serum with satisfactory results.
Manganese (Mn) single atom nanozyme with peroxidase-like activity was synthesized through a solvothermal method and used for the detection of alkaline phosphatase (ALP) activity. By using formamide as the carbon and nitrogen source and MnCl2 as the Mn source, formamide converted Mn and nitroren co-doped carbon (f-MnNC) could be obtained after reacting at 180℃ for 12 h. The structure and morphology were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffractometer, etc., and the peroxidase-like activity was investigated mainly using UV-visible absorption spectroscopy. In the presence of H2O2, f-MnNC could catalyze the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue oxidized TMB (oxTMB), with a characteristic absorption peak centered at 652 nm. ALP could catalyze the hydrolysis of L-ascorbic acid-2-phosphate (AA2P) to produce ascorbic acid (AA), which then reduced oxTMB to TMB, resulting in faded color and decreased absorbance. The degree of colorimetric signal change was related to ALP activity, and thus ALP activity could be quantitatively detected by employing AA2P as the substrate. In the activity range of 0.1-10 mU/mL, there was a good linear relationship between the absorbance at 652 nm and the ALP activity, and the detection limit (S/N=3) was 0.059 mU/mL. Other proteins and enzymes had no obvious interference with ALP detection, indicating good selectivity for ALP activity detection. The method was successfully applied to the determination of ALP activity in serum with satisfactory results.
2022, 50(1): 64-72
doi: 10.19756/j.issn.0253-3820.210717
Abstract:
A detection system based on g-C3N4 nanosheets, copper ions and o-phenylenediamine (OPD) was developed for detection of coenzyme A (CoA). By using chemically inert g-C3N4 nanosheets and oxOPD as fluorescent indicators, CoA formed a complex with Cu2+, which reduced the amount of free Cu2+ as an oxidant and quencher in the system, resulting in the OPD oxidation process being affected. Inhibition reduced the amount of oxOPD that was used as a quencher and a fluorescent indicator, resulting in the recovery of the fluorescence of g-C3N4 nanosheets, thereby changing the fluorescence intensity of the entire detection system. The ratio of the fluorescence emission intensity of g-C3N4 nanosheets to that of oxOPD (F440/F560) was used as the response signal for proportional fluorescence detection. Under the optimized experimental conditions, this method had a good proportional fluorescence response toward the concentration of CoA from 1.0 μmol/L to 100.0 μmol/L. The linear regression equation was F440/F560=0.00502CCoA (μmol/L)+0.1079 (R2=0.984). The detection limit (LOD=3 S/m) was 0.6 μmol/L. The constructed detection system had good selectivity, and was used to detect CoA in human serum samples, which proved that the system had the potential for detection of CoA in complex biological matrices.
A detection system based on g-C3N4 nanosheets, copper ions and o-phenylenediamine (OPD) was developed for detection of coenzyme A (CoA). By using chemically inert g-C3N4 nanosheets and oxOPD as fluorescent indicators, CoA formed a complex with Cu2+, which reduced the amount of free Cu2+ as an oxidant and quencher in the system, resulting in the OPD oxidation process being affected. Inhibition reduced the amount of oxOPD that was used as a quencher and a fluorescent indicator, resulting in the recovery of the fluorescence of g-C3N4 nanosheets, thereby changing the fluorescence intensity of the entire detection system. The ratio of the fluorescence emission intensity of g-C3N4 nanosheets to that of oxOPD (F440/F560) was used as the response signal for proportional fluorescence detection. Under the optimized experimental conditions, this method had a good proportional fluorescence response toward the concentration of CoA from 1.0 μmol/L to 100.0 μmol/L. The linear regression equation was F440/F560=0.00502CCoA (μmol/L)+0.1079 (R2=0.984). The detection limit (LOD=3 S/m) was 0.6 μmol/L. The constructed detection system had good selectivity, and was used to detect CoA in human serum samples, which proved that the system had the potential for detection of CoA in complex biological matrices.
2022, 50(1): 73-81
doi: 10.19756/j.issn.0253-3820.201750
Abstract:
Malachite green (MG), an effective insecticide and preservative, is commonly used in the aquaculture industry. However, MG has acute toxicity to terrestrial and aquatic animals, which can lead to mutagenicity, carcinogenicity, and teratogenicity on animals and human bodies. Therefore, it is necessary to explore a reliable and sensitive method for the rapid detection of MG. Herein, a novel and sensitive fluorescence-linked immunosorbent assay (FLISA) was constructed based on glod nanoclusters (BSA-AuNCs) for MG detection. The assay signal was originated from inner filter effect (IFE) between BSA-AuNCs and p-nitrophenol (PNP). Firstly, a double emission peak fluorescent gold nanocluster with good light stability and ultra-small size was quickly synthesized in 7 minutes, which was used as fluorescence probe in this immunoassay. Secondary, alkaline phosphatase labeled secondary antibody (IgG-ALP) was used to replace IgG-HRP in the immune reaction, which could generate PNP with the substrate of p-nitrophenyl phosphate (PNPP). As the maximum excitation wavelength of BSA-AuNCs (390 nm) overlapped with the absorption peak of PNP (400 nm), the fluorescence of BSA-AuNCs could be strongly quenched by PNP. Thus, with the absence of MG in the indirect immunoassay, much more IgG-ALP would be adsorbed in the 96-well plates, more PNP would be produced, then with the fluorescence quenched more strongly. The fluorescence signal could be used for MG detection indirectly. In this immunoassay, several factors including coating antigen, antibody concentration, secondary antibody concentration, substrate concentration, reaction temperature and reaction time were optimized. Under the optimized conditions, the linear range of this method was 0.1-100 ng/mL, linear equation was y=181.53lgCMG+241.3 (R2=0.995), and the limit of detection (LOD) was 0.089 ng/mL. The sensitivity of FLISA was 30 times that of ic-ELISA. Furthermore, the proposed method was successfully applied to determination of MG in spiked aquaculture water and tap water. The recoveries of MG were in the range of 84.0%-110.2%, and the coefficient of variation was 4.6%-11.2%. The new immunoassay could be used as a promising tool for rapid detection of MG in real environmental samples.
Malachite green (MG), an effective insecticide and preservative, is commonly used in the aquaculture industry. However, MG has acute toxicity to terrestrial and aquatic animals, which can lead to mutagenicity, carcinogenicity, and teratogenicity on animals and human bodies. Therefore, it is necessary to explore a reliable and sensitive method for the rapid detection of MG. Herein, a novel and sensitive fluorescence-linked immunosorbent assay (FLISA) was constructed based on glod nanoclusters (BSA-AuNCs) for MG detection. The assay signal was originated from inner filter effect (IFE) between BSA-AuNCs and p-nitrophenol (PNP). Firstly, a double emission peak fluorescent gold nanocluster with good light stability and ultra-small size was quickly synthesized in 7 minutes, which was used as fluorescence probe in this immunoassay. Secondary, alkaline phosphatase labeled secondary antibody (IgG-ALP) was used to replace IgG-HRP in the immune reaction, which could generate PNP with the substrate of p-nitrophenyl phosphate (PNPP). As the maximum excitation wavelength of BSA-AuNCs (390 nm) overlapped with the absorption peak of PNP (400 nm), the fluorescence of BSA-AuNCs could be strongly quenched by PNP. Thus, with the absence of MG in the indirect immunoassay, much more IgG-ALP would be adsorbed in the 96-well plates, more PNP would be produced, then with the fluorescence quenched more strongly. The fluorescence signal could be used for MG detection indirectly. In this immunoassay, several factors including coating antigen, antibody concentration, secondary antibody concentration, substrate concentration, reaction temperature and reaction time were optimized. Under the optimized conditions, the linear range of this method was 0.1-100 ng/mL, linear equation was y=181.53lgCMG+241.3 (R2=0.995), and the limit of detection (LOD) was 0.089 ng/mL. The sensitivity of FLISA was 30 times that of ic-ELISA. Furthermore, the proposed method was successfully applied to determination of MG in spiked aquaculture water and tap water. The recoveries of MG were in the range of 84.0%-110.2%, and the coefficient of variation was 4.6%-11.2%. The new immunoassay could be used as a promising tool for rapid detection of MG in real environmental samples.
2022, 50(1): 82-91
doi: 10.19756/j.issn.0253-3820.210593
Abstract:
The influence of ionization reagent on the determination results of non-polar polymers by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) was investigated. As a comparison, trans-2-[3-(4-tert-butylphenyl)-2-methyl-propylene] malononitrile (DCTB) was selected as the matrix, and polybutadiene 5000 (PB5000), polystyrene (PS) with different degree of polymerization and polyethylene 2000 (PE2000) were selected as the samples.The ionization of nine copper salts was investigated. The results showed that, under the same test conditions, copper nitrate could be used as an ionization reagent for the analysis of three kinds of non-polar polymers with the best signal intensity and resolution of the polymer spectra.In the analysis of PB5000, further cold-field scanning electron microscopy (SEM) analysis showed that copper nitrate mixed with PB5000 and DCTB could obtain more uniform crystallization in comparison with other copper salts.Using DCTC as the matrix and copper nitrate as the cation reagent, thin layer chromatography-matrix-assisted laser desorption ionization time of flight mass spectrometry (TLC-MALDI-TOF MS) coupling technology couldeffectively reduce or eliminate the influence of ion inhibition caused by dopants such as small molecule salt (sodium iodide) and other polymers (polyethylene glycol) which were easy to ionize in the analysis of polyolefin by MALDI-TOF. The effective analysis of impurity doped polymers PB5000 and PS4000 was realized successfully. This method had many advantages such as fast analysis speed, low cost and simple operation. This study provided an effective solution for MALDI-TOF MS analysis of low purity nonpolar polymers.
The influence of ionization reagent on the determination results of non-polar polymers by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) was investigated. As a comparison, trans-2-[3-(4-tert-butylphenyl)-2-methyl-propylene] malononitrile (DCTB) was selected as the matrix, and polybutadiene 5000 (PB5000), polystyrene (PS) with different degree of polymerization and polyethylene 2000 (PE2000) were selected as the samples.The ionization of nine copper salts was investigated. The results showed that, under the same test conditions, copper nitrate could be used as an ionization reagent for the analysis of three kinds of non-polar polymers with the best signal intensity and resolution of the polymer spectra.In the analysis of PB5000, further cold-field scanning electron microscopy (SEM) analysis showed that copper nitrate mixed with PB5000 and DCTB could obtain more uniform crystallization in comparison with other copper salts.Using DCTC as the matrix and copper nitrate as the cation reagent, thin layer chromatography-matrix-assisted laser desorption ionization time of flight mass spectrometry (TLC-MALDI-TOF MS) coupling technology couldeffectively reduce or eliminate the influence of ion inhibition caused by dopants such as small molecule salt (sodium iodide) and other polymers (polyethylene glycol) which were easy to ionize in the analysis of polyolefin by MALDI-TOF. The effective analysis of impurity doped polymers PB5000 and PS4000 was realized successfully. This method had many advantages such as fast analysis speed, low cost and simple operation. This study provided an effective solution for MALDI-TOF MS analysis of low purity nonpolar polymers.
2022, 50(1): 92-102
doi: 10.19756/j.issn.0253-3820.210716
Abstract:
Cinnamon oil (CO) shows a good antifungal activity against Candida Spp. However, the mechanism remains unclear, especially from the metabolic perspective. In this study, the effects of CO at subinhibitory concentration on Candida albicans were investigated by traditional microbiological method and measurement of lipids profile using a high-coverage lipidomics based on ultra-performance liquid chromatography-Q exactive-mass spectrometry (UPLC-QE-MS), combined with multivariate and univariate data statistical analyses. The results showed that the cell morphology of C.albicans was obviously changed when exposure to CO at subinhibitory concentration (0.1×MIC). A total of 1281 lipids species were identified in cells of C.albicans, which belong to 45 classes in 6 categories. Among them, 55 lipid species were significantly altered under CO treatment, mainly involving 15 lipids classes such as phosphatidylethanolamine (PE) and the derivative dimethylphosphatidylethanolamine (dMePE), phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylglycerol (PG), cardiolipin (CL), phosphatidylinositol (PI), ceramide (Cer) and the derivative hexosyl ceramide (Hex1Cer), triglyceride (TG), diglyceride (DG), etc. All but five lipid species were significantly down-regulated response to CO-treated treatment. The interaction network between the key lipid species with r>0.8 and p<0.05 was constructed by using hierarchical clustering analysis and correlation analysis. This study suggested that the antifungal effect of CO on C.albicans was potentially associated with the injured metabolic functions of cell membrane and mitochondria. The lipid species with significant difference expression level may be potentially metabolic markers for the inhibitory effect of CO against C.albicans.
Cinnamon oil (CO) shows a good antifungal activity against Candida Spp. However, the mechanism remains unclear, especially from the metabolic perspective. In this study, the effects of CO at subinhibitory concentration on Candida albicans were investigated by traditional microbiological method and measurement of lipids profile using a high-coverage lipidomics based on ultra-performance liquid chromatography-Q exactive-mass spectrometry (UPLC-QE-MS), combined with multivariate and univariate data statistical analyses. The results showed that the cell morphology of C.albicans was obviously changed when exposure to CO at subinhibitory concentration (0.1×MIC). A total of 1281 lipids species were identified in cells of C.albicans, which belong to 45 classes in 6 categories. Among them, 55 lipid species were significantly altered under CO treatment, mainly involving 15 lipids classes such as phosphatidylethanolamine (PE) and the derivative dimethylphosphatidylethanolamine (dMePE), phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylglycerol (PG), cardiolipin (CL), phosphatidylinositol (PI), ceramide (Cer) and the derivative hexosyl ceramide (Hex1Cer), triglyceride (TG), diglyceride (DG), etc. All but five lipid species were significantly down-regulated response to CO-treated treatment. The interaction network between the key lipid species with r>0.8 and p<0.05 was constructed by using hierarchical clustering analysis and correlation analysis. This study suggested that the antifungal effect of CO on C.albicans was potentially associated with the injured metabolic functions of cell membrane and mitochondria. The lipid species with significant difference expression level may be potentially metabolic markers for the inhibitory effect of CO against C.albicans.
2022, 50(1): 103-111
doi: 10.19756/j.issn.0253-3820.210563
Abstract:
SrAl2O4:Eu,Dy,La afterglow luminescence materials were prepared via a one-step combustion approach at a relatively low temperature by using aluminum nitrate, strontium nitrate and rare earth nitrate as oxidants, carbamide as reductants and fuels, and boric acid as fluxing agents. The preparation conditions including furnace temperature, amount of carbamide, amount of boric acid, and doping concentrations of La3+ ions were optimized. Then, the micromorphology, crystal structure, ultraviolet absorption property, and luminescence performance of as-prepared materials were characterized by scanning electron microscopy, X-ray diffraction pattern, ultraviolet-visible spectrum, and fluorescence emission spectrum, respectively. The prepared materials were polyhedral in shape with micron size, and monoclinal in phase with good crystallinity, which could emit strong luminescence at 514 nm under excitation of 252 or 334 nm ultraviolet light. After excited with 365 nm long-wavelength ultraviolet light for 30 s and then removing the excitation source, these materials could maintain strong green emission in dark field. Finally, the afterglow luminescence powders were applied for background-free development of latent fingerprints on various smooth substrates. The contrast, sensitivity and selectivity in fingerprint development were discussed in detail. After enhancing by afterglow luminescence treatment, the contrast between the developing signal and background noise were strong, all the detailed features of papillary ridges were obvious, and the adsorption between the developing powders and papillary ridges were specific, showing prominent advantages such as strong contrast, high sensitivity and good selectivity. Experimental results showed that, the method proposed here based on afterglow luminescence effect could achieve a high performance in background-free development of latent fingerprints on common substrates with smooth surface, especially on substrates with complex colors as well as strong fluorescence, exhibiting easy operability, high efficiency, and wide applicability.
SrAl2O4:Eu,Dy,La afterglow luminescence materials were prepared via a one-step combustion approach at a relatively low temperature by using aluminum nitrate, strontium nitrate and rare earth nitrate as oxidants, carbamide as reductants and fuels, and boric acid as fluxing agents. The preparation conditions including furnace temperature, amount of carbamide, amount of boric acid, and doping concentrations of La3+ ions were optimized. Then, the micromorphology, crystal structure, ultraviolet absorption property, and luminescence performance of as-prepared materials were characterized by scanning electron microscopy, X-ray diffraction pattern, ultraviolet-visible spectrum, and fluorescence emission spectrum, respectively. The prepared materials were polyhedral in shape with micron size, and monoclinal in phase with good crystallinity, which could emit strong luminescence at 514 nm under excitation of 252 or 334 nm ultraviolet light. After excited with 365 nm long-wavelength ultraviolet light for 30 s and then removing the excitation source, these materials could maintain strong green emission in dark field. Finally, the afterglow luminescence powders were applied for background-free development of latent fingerprints on various smooth substrates. The contrast, sensitivity and selectivity in fingerprint development were discussed in detail. After enhancing by afterglow luminescence treatment, the contrast between the developing signal and background noise were strong, all the detailed features of papillary ridges were obvious, and the adsorption between the developing powders and papillary ridges were specific, showing prominent advantages such as strong contrast, high sensitivity and good selectivity. Experimental results showed that, the method proposed here based on afterglow luminescence effect could achieve a high performance in background-free development of latent fingerprints on common substrates with smooth surface, especially on substrates with complex colors as well as strong fluorescence, exhibiting easy operability, high efficiency, and wide applicability.
2022, 50(1): 112-118
doi: 10.19756/j.issn.0253-3820.210555
Abstract:
Time-of-flight secondary ion mass spectrometry imaging (TOF-SIMSI) can not only obtain the third level characteristics of fingerprints, but also obtain the material information, which provides more possibilities for the evidential value of partial fingerprints lifted from crime scenes, especially for individual gender analysis based on fingerprint materials. In this work, TOF-SIMS technology combined with multi-layer perceptron neural network was used to explore the feasibility of population gender characteristics analysis based on fingerprint material ion signals. Firstly, the ion signals of 107 fingerprint substances shared by all volunteers detected by TOF-SIMS were analyzed by independent sample T test and the ion signals with significant differences were screened out. After dimension reduction by principal component analysis, they were input into the multi-layer perceptron neural network for gender classification and recognition. The results showed that the method correctly identified about 85% of males and 95% of females, and the total sample accuracy was about 90%. This work provided an effective method for further mining multidimensional information of partial fingerprints.
Time-of-flight secondary ion mass spectrometry imaging (TOF-SIMSI) can not only obtain the third level characteristics of fingerprints, but also obtain the material information, which provides more possibilities for the evidential value of partial fingerprints lifted from crime scenes, especially for individual gender analysis based on fingerprint materials. In this work, TOF-SIMS technology combined with multi-layer perceptron neural network was used to explore the feasibility of population gender characteristics analysis based on fingerprint material ion signals. Firstly, the ion signals of 107 fingerprint substances shared by all volunteers detected by TOF-SIMS were analyzed by independent sample T test and the ion signals with significant differences were screened out. After dimension reduction by principal component analysis, they were input into the multi-layer perceptron neural network for gender classification and recognition. The results showed that the method correctly identified about 85% of males and 95% of females, and the total sample accuracy was about 90%. This work provided an effective method for further mining multidimensional information of partial fingerprints.
2022, 50(1): 119-126
doi: 10.19756/j.issn.0253-3820.210524
Abstract:
As a new type of energy storage device, supercapacitors have been extensively studied due to their advantages such as high power density and long cycle life. Metal sulfide materials are often used as electrode materials for supercapacitors due to their high conductivity and good electrochemical performance. In this study, a one-step solvothermal method was used to prepare a CoNi2S4 material similar to the surface of broccoli with ethylene glycol as the solvent. The material had a synergistic effect of multiple ions during the Faraday redox reaction. The three-electrode test results showed that the material had good cycle stability and excellent charge and discharge performance. The specific capacitance was 2537 F/g at a current density of 1 A/g, and the specific capacitance retention rate was 88.2% after 5000 cycles. Compared with CoS, it had larger specific capacitance, specific surface area and better electrochemical performance. The assembled CoNi2S4//AC asymmetric supercapacitor had an energy density of 52.3 W/kg at a power density of 375 Wh/kg and a specific capacitance retention rate of 75.8% after 5000 cycles. The prepared CoNi2S4 was an excellent electrode material for supercapacitors.
As a new type of energy storage device, supercapacitors have been extensively studied due to their advantages such as high power density and long cycle life. Metal sulfide materials are often used as electrode materials for supercapacitors due to their high conductivity and good electrochemical performance. In this study, a one-step solvothermal method was used to prepare a CoNi2S4 material similar to the surface of broccoli with ethylene glycol as the solvent. The material had a synergistic effect of multiple ions during the Faraday redox reaction. The three-electrode test results showed that the material had good cycle stability and excellent charge and discharge performance. The specific capacitance was 2537 F/g at a current density of 1 A/g, and the specific capacitance retention rate was 88.2% after 5000 cycles. Compared with CoS, it had larger specific capacitance, specific surface area and better electrochemical performance. The assembled CoNi2S4//AC asymmetric supercapacitor had an energy density of 52.3 W/kg at a power density of 375 Wh/kg and a specific capacitance retention rate of 75.8% after 5000 cycles. The prepared CoNi2S4 was an excellent electrode material for supercapacitors.
2022, 50(1): 127-135
doi: 10.19756/j.issn.0253-3820.210715
Abstract:
Salmonella Paratyphi B (S.Paratyphi B) is one of the most widespread pathogenic bacteria causing foodborne disease. It is of great significance to construct a rapid and sensitive analysis method for detection of S.Paratyphi B. In this work, a simple, efficient and cost-effective surface bacteria-imprinted film-based impedance sensor was prepared. First of all, with S.Paratyphi B as the template and thiophene-3-ethanol as the functional monomer, the polythiophene and bacteria were co-deposited on the surface of glassy carbon electrode by cyclic voltammetry. After in situ removal of the template bacteria, a surface bacterial imprinting film was formed on the electrode surface, which could specifically recognize the target bacteria and successfully realize the label-free detection of the target bacteria. Under the optimal experimental conditions, this bacterial imprinted impedance sensor showed good analysis performance, e.g., fast recognition (10 min), wide linear range (1.0×101-1.0×106 CFU/mL), low detection limit (approximately 2.0 CFU/mL), and good selectivity. In addition, this impedance sensor could be successfully applied to detection of S.Paratyphi B in real samples with good recovery. Compared with the existing bacterial biosensor, the impedance sensor here had many advantages such as high preparation efficiency (only 5 min for imprinted film formation), low cost and environmental friendliness, showing potential applications in detection of foodborne pathogenic bacteria.
Salmonella Paratyphi B (S.Paratyphi B) is one of the most widespread pathogenic bacteria causing foodborne disease. It is of great significance to construct a rapid and sensitive analysis method for detection of S.Paratyphi B. In this work, a simple, efficient and cost-effective surface bacteria-imprinted film-based impedance sensor was prepared. First of all, with S.Paratyphi B as the template and thiophene-3-ethanol as the functional monomer, the polythiophene and bacteria were co-deposited on the surface of glassy carbon electrode by cyclic voltammetry. After in situ removal of the template bacteria, a surface bacterial imprinting film was formed on the electrode surface, which could specifically recognize the target bacteria and successfully realize the label-free detection of the target bacteria. Under the optimal experimental conditions, this bacterial imprinted impedance sensor showed good analysis performance, e.g., fast recognition (10 min), wide linear range (1.0×101-1.0×106 CFU/mL), low detection limit (approximately 2.0 CFU/mL), and good selectivity. In addition, this impedance sensor could be successfully applied to detection of S.Paratyphi B in real samples with good recovery. Compared with the existing bacterial biosensor, the impedance sensor here had many advantages such as high preparation efficiency (only 5 min for imprinted film formation), low cost and environmental friendliness, showing potential applications in detection of foodborne pathogenic bacteria.
2022, 50(1): 136-144
doi: 10.19756/j.issn.0253-3820.210454
Abstract:
Sulfurmustard (SM) is a typical representative of highly-toxic chemical warfare agent that is difficult to be prevented and treated. SM could produce various biomarkers with protein, glutathione and DNA, etc, besides oxidative and hydrolytic metabolism. The tripeptide-adduct hydroxyethylthioethyl-Cys-Pro-Pro (HETE-CPF) originating from Cys-34 on the human serum albumin (HSA) is a very important retrospective biomarker, which is usually used to identify SM exposure due to its long half-life and good stability. In this work, a novel synthetic route of HETE-CPF was developed with chloroethanol as the starting material. Compared with the original synthetic route using 2-chloroethyl mercaptoethanol as the starting material, the new synthetic method had less side reactions, higher yield and easier purification. Furthermore, a highly sensitive analysis method for HETE-CPF in whole blood samples was established, and the detection sensitivity was up to 2 ng/mL, which was enough to identify human plasma sample after exposure to SM. Meanwhile, it was also identified that after SM exposure via caudal vein in rats, the exposure biomarkers formed with plasma albumin were significantly different from those of human plasma, which was HETE-Cys-Pro-Tyr (HETE-CPY), not HETE-CPF. The fundamental reason might be due to their different primary sequence of albumin.
Sulfurmustard (SM) is a typical representative of highly-toxic chemical warfare agent that is difficult to be prevented and treated. SM could produce various biomarkers with protein, glutathione and DNA, etc, besides oxidative and hydrolytic metabolism. The tripeptide-adduct hydroxyethylthioethyl-Cys-Pro-Pro (HETE-CPF) originating from Cys-34 on the human serum albumin (HSA) is a very important retrospective biomarker, which is usually used to identify SM exposure due to its long half-life and good stability. In this work, a novel synthetic route of HETE-CPF was developed with chloroethanol as the starting material. Compared with the original synthetic route using 2-chloroethyl mercaptoethanol as the starting material, the new synthetic method had less side reactions, higher yield and easier purification. Furthermore, a highly sensitive analysis method for HETE-CPF in whole blood samples was established, and the detection sensitivity was up to 2 ng/mL, which was enough to identify human plasma sample after exposure to SM. Meanwhile, it was also identified that after SM exposure via caudal vein in rats, the exposure biomarkers formed with plasma albumin were significantly different from those of human plasma, which was HETE-Cys-Pro-Tyr (HETE-CPY), not HETE-CPF. The fundamental reason might be due to their different primary sequence of albumin.
2022, 50(1): 145-152
doi: 10.19756/j.issn.0253-3820.210411
Abstract:
Thirteen kinds of volatile disinfection by-products (V-DBPs) in water were determined by gas chromatography-triple quadrupole mass spectrometer (GC-MS/MS). GC-MS/MS was used to identify the precursor ions and product ions of 13 kinds of V-DBPs, and the operating parameters of chromatography and mass spectrometry were optimized. The optimal operation parameters of four typical sample pretreatment methods (liquid-liquid extraction (LLE), static headspace (SH), purge and trap (P&T) and solid phase microextraction (SPME) were determined, and their accuracy and precision were compared and analyzed. The standard curves of 13 kinds of V-DBPs were established using the optimized pretreatment method and instrument parameter setting. The results showed that the precision of the method was in accordance with SPME>SH>P&T>LLE when the concentration of 13 kinds of V-DBPs ranged from 0.05 μg/L to 100 μg/L. The four pretreatment methods had good detection precision when 2.5 and 25 μg/L mixed standards of V-DBPs were added to surface water, groundwater and tap water, and the accuracy of the method was in accordance with LLE, P&T>SH>SPME. The detection method based on GC-MS/MS was superior to the existing detection methods, and could meet the needs of rapid and accurate determination of 13 kinds of V-DBPs in discharge water after disinfection.
Thirteen kinds of volatile disinfection by-products (V-DBPs) in water were determined by gas chromatography-triple quadrupole mass spectrometer (GC-MS/MS). GC-MS/MS was used to identify the precursor ions and product ions of 13 kinds of V-DBPs, and the operating parameters of chromatography and mass spectrometry were optimized. The optimal operation parameters of four typical sample pretreatment methods (liquid-liquid extraction (LLE), static headspace (SH), purge and trap (P&T) and solid phase microextraction (SPME) were determined, and their accuracy and precision were compared and analyzed. The standard curves of 13 kinds of V-DBPs were established using the optimized pretreatment method and instrument parameter setting. The results showed that the precision of the method was in accordance with SPME>SH>P&T>LLE when the concentration of 13 kinds of V-DBPs ranged from 0.05 μg/L to 100 μg/L. The four pretreatment methods had good detection precision when 2.5 and 25 μg/L mixed standards of V-DBPs were added to surface water, groundwater and tap water, and the accuracy of the method was in accordance with LLE, P&T>SH>SPME. The detection method based on GC-MS/MS was superior to the existing detection methods, and could meet the needs of rapid and accurate determination of 13 kinds of V-DBPs in discharge water after disinfection.
2022, 50(1): 153-161
doi: 10.19756/j.issn.0253-3820.210687
Abstract:
Micro-extraction tube injection (METI), a needle-typed micro-extraction technology, has been proposed for gas chromatography (GC). In METI, a section of monolithic capillary tube (5 cm in length) works as an extraction tube and also as an injection needle. Based on the strategy of static desorption in tube and direct injection with tube, METI is able to enrich analytes at ng/L level in water for GC analysis when 1 mL of sample is consumed. In this work, the monolithic capillary tube was prepared with N-vinylpyrrolidone (NVP) and divinylbenzene (DVB), and four kinds of illicit drugs including methamphetamine, ketamine, norketamine and cocaine were tested. After the conditions of METI were optimized, a method of METI coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was established for determination of illicit drugs in wastewater. The linear ranges were 0.05-50 μg/L for methamphetamine, ketamine and norketamine, and 0.10-50 μg/L for cocaine with the correlation coefficients (R2) greater than 0.9985. The limits of detection (S/N=3) of the analytes varied from 0.32 to 10.00 ng/L, and the limits of quantification (S/N=10) were in the range of 1.07-33.00 ng/L. The spiking recoveries ranged from 74.65% to 114.36% at spiking levels of 0.3, 3.0 and 30.0 μg/L in water samples from East Lake and intake of wastewater treatment plant, and relative standard deviations (RSDs) were less than 10.6%, except for cocaine which was 15.0% at low concentration in East Lake water. METI integrated separation, enrichment and injection, with the advantages including simple operation and high enrichment efficiency, and could be used for rapid pretreatment of trace components in small amounts of samples.
Micro-extraction tube injection (METI), a needle-typed micro-extraction technology, has been proposed for gas chromatography (GC). In METI, a section of monolithic capillary tube (5 cm in length) works as an extraction tube and also as an injection needle. Based on the strategy of static desorption in tube and direct injection with tube, METI is able to enrich analytes at ng/L level in water for GC analysis when 1 mL of sample is consumed. In this work, the monolithic capillary tube was prepared with N-vinylpyrrolidone (NVP) and divinylbenzene (DVB), and four kinds of illicit drugs including methamphetamine, ketamine, norketamine and cocaine were tested. After the conditions of METI were optimized, a method of METI coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was established for determination of illicit drugs in wastewater. The linear ranges were 0.05-50 μg/L for methamphetamine, ketamine and norketamine, and 0.10-50 μg/L for cocaine with the correlation coefficients (R2) greater than 0.9985. The limits of detection (S/N=3) of the analytes varied from 0.32 to 10.00 ng/L, and the limits of quantification (S/N=10) were in the range of 1.07-33.00 ng/L. The spiking recoveries ranged from 74.65% to 114.36% at spiking levels of 0.3, 3.0 and 30.0 μg/L in water samples from East Lake and intake of wastewater treatment plant, and relative standard deviations (RSDs) were less than 10.6%, except for cocaine which was 15.0% at low concentration in East Lake water. METI integrated separation, enrichment and injection, with the advantages including simple operation and high enrichment efficiency, and could be used for rapid pretreatment of trace components in small amounts of samples.
