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2021 Volume 49 Issue 5
2021, 49(5): 653-664
doi: 10.19756/j.issn.0253-3820.211037
Abstract:
Gold thin films have attracted a growing number attention because of their advantages such as easy preparation, conveniently subsequent modifications, good chemical stability, high electrical conductivity and low cytotoxicity. The preparation of continuous metal layer on capillary has become a classic leading step in the field of analytical chemistry. In recent years, researchers have established a variety of methods to prepare gold thin films, which has been applied in many fields. This paper reviews the preparation methods of gold thin films based on capillary, and its application in electrochemical sensing analysis, mainly discussing the technical characteristics and research status of electroless deposition, electrochemical deposition and physical vapor deposition. In addition, the development prospects of gold plating on capillary are also prospected.
Gold thin films have attracted a growing number attention because of their advantages such as easy preparation, conveniently subsequent modifications, good chemical stability, high electrical conductivity and low cytotoxicity. The preparation of continuous metal layer on capillary has become a classic leading step in the field of analytical chemistry. In recent years, researchers have established a variety of methods to prepare gold thin films, which has been applied in many fields. This paper reviews the preparation methods of gold thin films based on capillary, and its application in electrochemical sensing analysis, mainly discussing the technical characteristics and research status of electroless deposition, electrochemical deposition and physical vapor deposition. In addition, the development prospects of gold plating on capillary are also prospected.
2021, 49(5): 665-675
doi: 10.19756/j.issn.0253-3820.201722
Abstract:
Electrochemiluminescence (ECL) is the process of producing species on the surface of electrodes and the subsequent formation of excited luminescence through electron transfer reaction. Organic polymeric materials are constructed by one or more molecules/molecular groups (structural units or monomers) which are covalently bonded to form multiple repeating monomer units. Organic polymers include metal-organic frameworks (MOFs), metal-organic gels (MOGs), conjugated microporous polymers (CMPs) and polymer dots (Pdots). In comparison with the cadmium-containing quantum dots, organic polymer materials have significant advantages including low toxicity and good biocompatibility, and they not only function as the ECL emitter, but also enhance the ECL signal. The organic polymer-based ECL sensors are characterized by good selectivity, high specificity, simple equipment, stable signal, easy measurement, high sensitivity, wide dynamic range, and low background, and they are widely applied to environmental monitoring, immunoassay, and nucleic acids analysis. This review summarizes the recent advance in applications of organic polymer-based ECL sensors in biochemical analysis, and focuses on the selective detection of metal ions, small biological molecules, nucleic acids, and proteins. In addition, we highlight the challenges and trends in the development of organic polymer-based ECL sensors.
Electrochemiluminescence (ECL) is the process of producing species on the surface of electrodes and the subsequent formation of excited luminescence through electron transfer reaction. Organic polymeric materials are constructed by one or more molecules/molecular groups (structural units or monomers) which are covalently bonded to form multiple repeating monomer units. Organic polymers include metal-organic frameworks (MOFs), metal-organic gels (MOGs), conjugated microporous polymers (CMPs) and polymer dots (Pdots). In comparison with the cadmium-containing quantum dots, organic polymer materials have significant advantages including low toxicity and good biocompatibility, and they not only function as the ECL emitter, but also enhance the ECL signal. The organic polymer-based ECL sensors are characterized by good selectivity, high specificity, simple equipment, stable signal, easy measurement, high sensitivity, wide dynamic range, and low background, and they are widely applied to environmental monitoring, immunoassay, and nucleic acids analysis. This review summarizes the recent advance in applications of organic polymer-based ECL sensors in biochemical analysis, and focuses on the selective detection of metal ions, small biological molecules, nucleic acids, and proteins. In addition, we highlight the challenges and trends in the development of organic polymer-based ECL sensors.
2021, 49(5): 676-685
doi: 10.19756/j.issn.0253-3820.201536
Abstract:
Noble metal nanomaterials are widely used in analytical chemistry due to their unique physical and chemical properties. However, the instability of nanoparticles in aqueous solutions limits the development of noble metal nanomaterials. Hydrogels acting as nanoparticle carriers can solve this problem well. Due to the excellent mechanical properties, good biocompatibility and easy modification, hydrogels can improve the properties of nanomaterials and provide new application advantages. Therefore, more and more researches focus on the development of noble metal nanoparticles and hydrogel composite materials. Here, we reviewed the preparation principles and application progress of various types of noble metal nanoparticles and hydrogel composite materials in the past five years, and analyzed the application advantages of composite materials and their further research orientations.
Noble metal nanomaterials are widely used in analytical chemistry due to their unique physical and chemical properties. However, the instability of nanoparticles in aqueous solutions limits the development of noble metal nanomaterials. Hydrogels acting as nanoparticle carriers can solve this problem well. Due to the excellent mechanical properties, good biocompatibility and easy modification, hydrogels can improve the properties of nanomaterials and provide new application advantages. Therefore, more and more researches focus on the development of noble metal nanoparticles and hydrogel composite materials. Here, we reviewed the preparation principles and application progress of various types of noble metal nanoparticles and hydrogel composite materials in the past five years, and analyzed the application advantages of composite materials and their further research orientations.
2021, 49(5): 686-692
doi: 10.19756/j.issn.0253-3820.201397
Abstract:
A 200-cm-long, 300 μm-depth and 80 μm-wide gas chromatographic (GC) column was fabricated on the silicon chip by microelectromechanical system (MEMS) technique in this work. Unlike the traditional open gas chromatographic column, the design and fabrication of the MEMS-based GC column folded in a wavy configuration which was filled with a circular micro column with a diameter of 30 μm. The size, shape and distribution of the semi-packed column in the prepared micro-chromatographic column were analyzed by finite element analysis software to obtain the optimized preparation parameters. The simulation revealed that MEMS-based semi-packed gas chromatography wavy column achieved an even flow velocity, resulting in a successive improvement of the flow uniformity at the zones between two adjacent bends, as well as a more nonsymmetric distribution at the bends. Benzene and toluene were separated by the fabricated GC column within 1.5 min. In addition, the N-alkane component were separated and the plate number reached 4790 plates/m.
A 200-cm-long, 300 μm-depth and 80 μm-wide gas chromatographic (GC) column was fabricated on the silicon chip by microelectromechanical system (MEMS) technique in this work. Unlike the traditional open gas chromatographic column, the design and fabrication of the MEMS-based GC column folded in a wavy configuration which was filled with a circular micro column with a diameter of 30 μm. The size, shape and distribution of the semi-packed column in the prepared micro-chromatographic column were analyzed by finite element analysis software to obtain the optimized preparation parameters. The simulation revealed that MEMS-based semi-packed gas chromatography wavy column achieved an even flow velocity, resulting in a successive improvement of the flow uniformity at the zones between two adjacent bends, as well as a more nonsymmetric distribution at the bends. Benzene and toluene were separated by the fabricated GC column within 1.5 min. In addition, the N-alkane component were separated and the plate number reached 4790 plates/m.
2021, 49(5): 693-701
doi: 10.19756/j.issn.0253-3820.211011
Abstract:
The printed circuit board ion trap (PCBIT) is a mass analyzer with a unique discrete electrode structure, so the electric fields inside could be flexibly adjusted. Previous researches of PCBIT mainly concentrated on the optimization of the radio-frequency (RF) electric fields, which was usually realized by modifying the geometric parameters or the voltage divided ratio of RF voltage (α). In this work, a new method was proposed to further improve the performance of PCBIT. That is, the resonant excitation electric field was optimized in company with the geometric parameters of PCBIT. During the simulation, the geometric parameters of PCBIT were firstly modified to optimize the internal RF electric fields, seeking for greater mass resolution. Then the resonant excitation electric field was optimized by adjusting voltage divided ratio of resonant excitation signal (γ). And the ion trajectories and simulated mass spectrum were also calculated. The results showed that it could be impossible to improve mass resolution significantly by optimizing the RF electric fields only, while the optimization of resonant excitation field could significantly improve the mass resolution. To achieve great analysis performance, the γ value should be set up at a relatively low level. For ions at m/z 1891 Da, the optimal mass resolution of over 14500 (FWHM) was obtained in an optimized PCBIT with γ=2%, which was much higher than that achieved in traditional optimization methods. This novel method provided a simple and practical approach for developing miniature ion trap mass analyzer with high performance.
The printed circuit board ion trap (PCBIT) is a mass analyzer with a unique discrete electrode structure, so the electric fields inside could be flexibly adjusted. Previous researches of PCBIT mainly concentrated on the optimization of the radio-frequency (RF) electric fields, which was usually realized by modifying the geometric parameters or the voltage divided ratio of RF voltage (α). In this work, a new method was proposed to further improve the performance of PCBIT. That is, the resonant excitation electric field was optimized in company with the geometric parameters of PCBIT. During the simulation, the geometric parameters of PCBIT were firstly modified to optimize the internal RF electric fields, seeking for greater mass resolution. Then the resonant excitation electric field was optimized by adjusting voltage divided ratio of resonant excitation signal (γ). And the ion trajectories and simulated mass spectrum were also calculated. The results showed that it could be impossible to improve mass resolution significantly by optimizing the RF electric fields only, while the optimization of resonant excitation field could significantly improve the mass resolution. To achieve great analysis performance, the γ value should be set up at a relatively low level. For ions at m/z 1891 Da, the optimal mass resolution of over 14500 (FWHM) was obtained in an optimized PCBIT with γ=2%, which was much higher than that achieved in traditional optimization methods. This novel method provided a simple and practical approach for developing miniature ion trap mass analyzer with high performance.
2021, 49(5): 702-709
doi: 10.19756/j.issn.0253-3820.201765
Abstract:
Telomerase is a ribonucleoprotein that can catalyze the addition of telomerase repeats onto the end of telomere, compensating for the telomere shortening during cell division and maintaining the continuous cell proliferation. Telomerase activity is overexpressed in cancerous cells but inhibited in normal somatic cells, and thus it is regarded as an important biomarker for cancer diagnosis and prognosis evaluation. In this work, a test strip is constructed for visual detection of telomerase activity and determination of cancerous cells. The test strip is constituted of sample pad, conjugate pad that is sprayed with DNA-functionalized gold nanoparticles, nitrocellulose membrane that contains test zone and control zone, and absorbent pad, which are all assembled onto the backing plate. Under the action of telomerase, the substrate sequence gets extended, which are then dropped onto the sample pad. The solution migrates by capillary action and rehydrates the DNA-functionalized AuNPs on the conjugate pad. Subsequently, the telomeric products hybridize with the capture DNA in the test zone and the modified DNA on AuNPs in a sandwich manner, causing the accumulation of AuNPs on the test zone and the color development of T-line. Meanwhile, the DNA-functionalized AuNPs continue flowing and then hybridize with the capture DNA on the control zone, causing the color development of C-line and confirming the validity of the test strip. Through responding to the telomerase from cell extracts, the method can achieve the visual differentiation of cancerous cells from normal cells in a convenient and rapid way by observation of color development of T-line.
Telomerase is a ribonucleoprotein that can catalyze the addition of telomerase repeats onto the end of telomere, compensating for the telomere shortening during cell division and maintaining the continuous cell proliferation. Telomerase activity is overexpressed in cancerous cells but inhibited in normal somatic cells, and thus it is regarded as an important biomarker for cancer diagnosis and prognosis evaluation. In this work, a test strip is constructed for visual detection of telomerase activity and determination of cancerous cells. The test strip is constituted of sample pad, conjugate pad that is sprayed with DNA-functionalized gold nanoparticles, nitrocellulose membrane that contains test zone and control zone, and absorbent pad, which are all assembled onto the backing plate. Under the action of telomerase, the substrate sequence gets extended, which are then dropped onto the sample pad. The solution migrates by capillary action and rehydrates the DNA-functionalized AuNPs on the conjugate pad. Subsequently, the telomeric products hybridize with the capture DNA in the test zone and the modified DNA on AuNPs in a sandwich manner, causing the accumulation of AuNPs on the test zone and the color development of T-line. Meanwhile, the DNA-functionalized AuNPs continue flowing and then hybridize with the capture DNA on the control zone, causing the color development of C-line and confirming the validity of the test strip. Through responding to the telomerase from cell extracts, the method can achieve the visual differentiation of cancerous cells from normal cells in a convenient and rapid way by observation of color development of T-line.
2021, 49(5): 710-717
doi: 10.19756/j.issn.0253-3820.201717
Abstract:
Based on the high affinity and specific target recognition function of the aptamer for metastatic tumor cells, aptamer-functionalized magnetic beads (W3-beads) that could specifically recognize and enrich metastatic colorectal cancer cells were formed using the biotin-streptavidin cross-linking method. Aptamer W3 maintained specific binding ability to target cells at room temperature and in human plasma environment. W3-beads prepared by modifying magnetic beads effectively captured target cells in mixed cells of target cells/non-target cells in different ratios. When the number of target cells exceeded 103 per milliliter, the capture efficiency of W3-beads exceeded 75%, and the actual detection limit reached 50 cells per milliliter. Besides, the calibration formula between the initial number of cells and the number of captured cells was y=0.7253x-5.1199 (R2=0.9967). Incorporating target cells into whole blood to simulate circulating tumor cells, W3-beads effectively captured and enriched target cells in whole blood. The aptamer-functioned magnetic beads constructed in this experiment had good targeted capture, separation and enrichment capabilities for metastatic colorectal cancer cells, and provided an effective and convenient tool for enrichment of circulating tumor cells in the blood samples of colorectal cancer patients.
Based on the high affinity and specific target recognition function of the aptamer for metastatic tumor cells, aptamer-functionalized magnetic beads (W3-beads) that could specifically recognize and enrich metastatic colorectal cancer cells were formed using the biotin-streptavidin cross-linking method. Aptamer W3 maintained specific binding ability to target cells at room temperature and in human plasma environment. W3-beads prepared by modifying magnetic beads effectively captured target cells in mixed cells of target cells/non-target cells in different ratios. When the number of target cells exceeded 103 per milliliter, the capture efficiency of W3-beads exceeded 75%, and the actual detection limit reached 50 cells per milliliter. Besides, the calibration formula between the initial number of cells and the number of captured cells was y=0.7253x-5.1199 (R2=0.9967). Incorporating target cells into whole blood to simulate circulating tumor cells, W3-beads effectively captured and enriched target cells in whole blood. The aptamer-functioned magnetic beads constructed in this experiment had good targeted capture, separation and enrichment capabilities for metastatic colorectal cancer cells, and provided an effective and convenient tool for enrichment of circulating tumor cells in the blood samples of colorectal cancer patients.
2021, 49(5): 718-725
doi: 10.19756/j.issn.0253-3820.191695
Abstract:
A novel magnetoelastic (ME) aptasensor containing aptamer functionalized gold-coated ME chip was developed for carcinoembryonic antigen (CEA) detection. Due to its magnetostrictive properties, the signals could be wirelessly detected through magnetic field, which made it potentially suitable for in vivo analysis. The conjugation of aptamers and CEA was successfully confirmed by scanning electron microscopy, atomic force microscopy and energy dispersive spectroscopy. With the optimum modification concentration of CEA-Apt, the ME aptasensor demonstrated a linear range from 1 ng/mL to 100 ng/mL towards CEA concentration with a detection limit (LOD) of 0.09 ng/mL. Clinical chemiluminescence assay (CA method) was carried out to certify the feasibility of the ME aptasensor. The ME aptasensor exhibited excellent selectivity, stability and repeatability towards CEA, which provided a promising method for clinical diagnosis of cancer.
A novel magnetoelastic (ME) aptasensor containing aptamer functionalized gold-coated ME chip was developed for carcinoembryonic antigen (CEA) detection. Due to its magnetostrictive properties, the signals could be wirelessly detected through magnetic field, which made it potentially suitable for in vivo analysis. The conjugation of aptamers and CEA was successfully confirmed by scanning electron microscopy, atomic force microscopy and energy dispersive spectroscopy. With the optimum modification concentration of CEA-Apt, the ME aptasensor demonstrated a linear range from 1 ng/mL to 100 ng/mL towards CEA concentration with a detection limit (LOD) of 0.09 ng/mL. Clinical chemiluminescence assay (CA method) was carried out to certify the feasibility of the ME aptasensor. The ME aptasensor exhibited excellent selectivity, stability and repeatability towards CEA, which provided a promising method for clinical diagnosis of cancer.
2021, 49(5): 726-732
doi: 10.19756/j.issn.0253-3820.201381
Abstract:
A novel poly(acrylic acid)-Tb@SiO2 (PAA-Tb@SiO2) fluorescent probe was constructed for detection of 2,6-pyridinedicarboxylic acid (DPA) that was regarded as the potential biomarkers of anthrax. The DPA could coordinate with Tb3+ in this probe, which produced an "antenna effect" to enhance the fluorescence intensity of the probe. There was a good linear relationship between fluorescence intensity and DPA concentration in the range of 0.1-20.0 μmol/L, and the correlation coefficient (R2) was 0.9978. The detection limit was 6 nmol/L (3σ). The established method realized the detection of DPA in tap water, the recoveries of the spike were between 94.6% and 116.8%, and the RSD was less than 2%. The method had high sensitivity and good selectivity, and could be used for the analysis of anthrax in environmental water samples.
A novel poly(acrylic acid)-Tb@SiO2 (PAA-Tb@SiO2) fluorescent probe was constructed for detection of 2,6-pyridinedicarboxylic acid (DPA) that was regarded as the potential biomarkers of anthrax. The DPA could coordinate with Tb3+ in this probe, which produced an "antenna effect" to enhance the fluorescence intensity of the probe. There was a good linear relationship between fluorescence intensity and DPA concentration in the range of 0.1-20.0 μmol/L, and the correlation coefficient (R2) was 0.9978. The detection limit was 6 nmol/L (3σ). The established method realized the detection of DPA in tap water, the recoveries of the spike were between 94.6% and 116.8%, and the RSD was less than 2%. The method had high sensitivity and good selectivity, and could be used for the analysis of anthrax in environmental water samples.
2021, 49(5): 733-742
doi: 10.19756/j.issn.0253-3820.211054
Abstract:
Bacterial membrane vesicles (BMVs) are nanostructures shed naturally by most bacterial species. BMVs carry nucleic acids, proteins, especially virulence factors and immune regulatory factors for the inter- and intra-species communication, showing great potential in the development of vaccines and anticancer drugs. However, the purification and characterization of BMVs remain challenging due to their large heterogeneity, nanoscale particle size, and low contents of cargo molecules. Based on the unique advantages such as the laboratory-built nano-flow cytometer (nFCM) in the sensitive and rapid analysis of individual nanoparticles, the purity, concentration and size distribution of BMV preparations were measured in this work. The experimental results demonstrated that the components in each density layer after density gradient centrifugation could be detected by nFCM to obtain BMVs samples with a high purity of more than 90%. BMVs secreted by Gram-positive bacteria S.aureus and Gram-negative bacteria E.coli O157:H7 were significantly different in density, which mainly presented in the second (ρ=1.06 g/mL) and fourth (ρ=1.10 g/mL) fractions of the Optiprep density gradient layer respectively. The median particle sizes of BMVs derived from Gram-positive (S.aureus) and Gram-negative (E.coli O157:H7) bacteria were 64.9 nm and 83.5 nm, respectively. In conclusion, the study presented here reported the development of an efficient method to characterize the purity, concentration, and size distribution of BMVs at the single-particle level. nFCM was expected to provide powerful technical support for the biological function study of BMVs.
Bacterial membrane vesicles (BMVs) are nanostructures shed naturally by most bacterial species. BMVs carry nucleic acids, proteins, especially virulence factors and immune regulatory factors for the inter- and intra-species communication, showing great potential in the development of vaccines and anticancer drugs. However, the purification and characterization of BMVs remain challenging due to their large heterogeneity, nanoscale particle size, and low contents of cargo molecules. Based on the unique advantages such as the laboratory-built nano-flow cytometer (nFCM) in the sensitive and rapid analysis of individual nanoparticles, the purity, concentration and size distribution of BMV preparations were measured in this work. The experimental results demonstrated that the components in each density layer after density gradient centrifugation could be detected by nFCM to obtain BMVs samples with a high purity of more than 90%. BMVs secreted by Gram-positive bacteria S.aureus and Gram-negative bacteria E.coli O157:H7 were significantly different in density, which mainly presented in the second (ρ=1.06 g/mL) and fourth (ρ=1.10 g/mL) fractions of the Optiprep density gradient layer respectively. The median particle sizes of BMVs derived from Gram-positive (S.aureus) and Gram-negative (E.coli O157:H7) bacteria were 64.9 nm and 83.5 nm, respectively. In conclusion, the study presented here reported the development of an efficient method to characterize the purity, concentration, and size distribution of BMVs at the single-particle level. nFCM was expected to provide powerful technical support for the biological function study of BMVs.
2021, 49(5): 743-751
doi: 10.19756/j.issn.0253-3820.201706
Abstract:
The long single-stranded DNA containing multiple copy units prepared by rolling circle amplification technique was used as a scaffold strand. The scaffold strands were hybridized to three short staple strands at special positions by the molecular self-assembly and formed DNA origami belt. On the basis of the principle of SYBR Green real-time fluorescence quantitative PCR method and atomic force microscopy (AFM) imaging technology, the formation of double-stranded structure was examined by the change of fluorescence signal intensity in the reaction solution while the morphology of DNA belts was observed by AFM straightly. The effect of pH on the stability of DNA belt was studied, and its performance of pH-resistant in the wide range of pH=3-11 was obtained. DNA belts exhibited the best stability in neutral pH enviroment (pH=7), which showed a significantly higher fluorescence signal than that of other groups within 24 h. DNA belts had poor resistance to acid and alkali environment, especially extreme pH conditions (pH=3, pH=11). At extreme pH, even instantaneous treatments (<10 s) could have significant effects on the DNA belts, causing a rapid decrease in the fluorescence signal intensity of the solution. Further, the characterization results of AFM and agarose gel showed that the morphological destruction of DNA belts in extreme pH environment (pH=3) was a continuous and irreversible process. The DNA belts with a width of 16 nm and a length of micrometer became shorter and thinner with the processing time. It was speculated that the hydrogen bond which held the double-stranded structure of DNA belts was broken first, and then the phosphodiester linkage between nucleotides as well as the glycoside bond inside nucleotide, resulting in broken DNA belts in pieces finally.
The long single-stranded DNA containing multiple copy units prepared by rolling circle amplification technique was used as a scaffold strand. The scaffold strands were hybridized to three short staple strands at special positions by the molecular self-assembly and formed DNA origami belt. On the basis of the principle of SYBR Green real-time fluorescence quantitative PCR method and atomic force microscopy (AFM) imaging technology, the formation of double-stranded structure was examined by the change of fluorescence signal intensity in the reaction solution while the morphology of DNA belts was observed by AFM straightly. The effect of pH on the stability of DNA belt was studied, and its performance of pH-resistant in the wide range of pH=3-11 was obtained. DNA belts exhibited the best stability in neutral pH enviroment (pH=7), which showed a significantly higher fluorescence signal than that of other groups within 24 h. DNA belts had poor resistance to acid and alkali environment, especially extreme pH conditions (pH=3, pH=11). At extreme pH, even instantaneous treatments (<10 s) could have significant effects on the DNA belts, causing a rapid decrease in the fluorescence signal intensity of the solution. Further, the characterization results of AFM and agarose gel showed that the morphological destruction of DNA belts in extreme pH environment (pH=3) was a continuous and irreversible process. The DNA belts with a width of 16 nm and a length of micrometer became shorter and thinner with the processing time. It was speculated that the hydrogen bond which held the double-stranded structure of DNA belts was broken first, and then the phosphodiester linkage between nucleotides as well as the glycoside bond inside nucleotide, resulting in broken DNA belts in pieces finally.
2021, 49(5): 752-758
doi: 10.19756/j.issn.0253-3820.191515
Abstract:
By now, genetically modified crops have been widely planted in the world. It is an urgent need not only to conduct qualitative testing of transgenes crop, but also to conduct rapid quantitative analysis of exogenous protein content expressed in transgenic crops, so as to judge the resistance to insects or herbicides. Two mouse monoclonal antibodies that recognize different epitopes of Bt Cry1Ab/Ac have been prepared in the previous work. On this basis, time-resolved fluorescent strips of Bt Cry1Ab/Ac were prepared using fluorescent microspheres as markers in this work. Combined with portable fluorescence immunoanalyzer, a lateral flow immunoassay was developed for the quantitative analysis of exogenous protein Bt Cry1Ac in transgenic crops. The detection time was 20 min, the linear equation of the standard curve was y=0.5804x-1.9123, with correlation coefficient (R2) of 0.998. The limit of quantitation was 1.5 ng/mL. With the established method, the content of Bt Cry1Ab/Ac protein in samples was determined, and the results were compared with those of commercial kit with detection time of 1.5 h. The results of these two methods correlated well (R2=0.999). The time-resolved fluorescent strip established here could be used as a rapid and accurate quantitative method for determination of Bt cry1Ab/Ac in transgenic crops.
By now, genetically modified crops have been widely planted in the world. It is an urgent need not only to conduct qualitative testing of transgenes crop, but also to conduct rapid quantitative analysis of exogenous protein content expressed in transgenic crops, so as to judge the resistance to insects or herbicides. Two mouse monoclonal antibodies that recognize different epitopes of Bt Cry1Ab/Ac have been prepared in the previous work. On this basis, time-resolved fluorescent strips of Bt Cry1Ab/Ac were prepared using fluorescent microspheres as markers in this work. Combined with portable fluorescence immunoanalyzer, a lateral flow immunoassay was developed for the quantitative analysis of exogenous protein Bt Cry1Ac in transgenic crops. The detection time was 20 min, the linear equation of the standard curve was y=0.5804x-1.9123, with correlation coefficient (R2) of 0.998. The limit of quantitation was 1.5 ng/mL. With the established method, the content of Bt Cry1Ab/Ac protein in samples was determined, and the results were compared with those of commercial kit with detection time of 1.5 h. The results of these two methods correlated well (R2=0.999). The time-resolved fluorescent strip established here could be used as a rapid and accurate quantitative method for determination of Bt cry1Ab/Ac in transgenic crops.
2021, 49(5): 759-767
doi: 10.19756/j.issn.0253-3820.201596
Abstract:
A polymethacrylic acid-protected silver nanocluster with fluorescence (AgNCs@PMAA) was prepared in one step using ultraviolet light irradiation. Based on the fact that the interaction between iodine and AgNCs@PMAA could cause fluorescence quenching and characteristic absorption, a dual response method for determination of iodine by fluorescence emission spectrometry and UV-vis absorption spectrometry was established. The prepared AgNCs@PMAA was characterized by TEM, XPS and FTIR, and the results showed that the AgNCs@PMAA had uniform small nanometer size and strong fluorescence luminescence, however, the fusion effect of iodine on AgNCs@PMAA could cause changes in its composition and morphology. Based on the linear relationship between the fluorescence emission peak and absorption peak intensity change of AgNCs@PMAA and the concentration of iodine elemental substance, two methods and visual detection method for detecting iodine were established and applied to actual sample determination. The fluorescence quenching efficiency of AgNCs@PMAA was linearly correlated with I2 concentration within the range of 1.0-90.0 μg/mL, and the detection limit was 0.168 μg/mL (S/N=3). The fluorescent probe was applied to the determination of iodine in iodine tincture samples with recoveries of 100.5%-100.9%, and the relative standard deviations were less than 4.7%. The optical probe combined with multiple detection methods showed good practical significance and application prospects.
A polymethacrylic acid-protected silver nanocluster with fluorescence (AgNCs@PMAA) was prepared in one step using ultraviolet light irradiation. Based on the fact that the interaction between iodine and AgNCs@PMAA could cause fluorescence quenching and characteristic absorption, a dual response method for determination of iodine by fluorescence emission spectrometry and UV-vis absorption spectrometry was established. The prepared AgNCs@PMAA was characterized by TEM, XPS and FTIR, and the results showed that the AgNCs@PMAA had uniform small nanometer size and strong fluorescence luminescence, however, the fusion effect of iodine on AgNCs@PMAA could cause changes in its composition and morphology. Based on the linear relationship between the fluorescence emission peak and absorption peak intensity change of AgNCs@PMAA and the concentration of iodine elemental substance, two methods and visual detection method for detecting iodine were established and applied to actual sample determination. The fluorescence quenching efficiency of AgNCs@PMAA was linearly correlated with I2 concentration within the range of 1.0-90.0 μg/mL, and the detection limit was 0.168 μg/mL (S/N=3). The fluorescent probe was applied to the determination of iodine in iodine tincture samples with recoveries of 100.5%-100.9%, and the relative standard deviations were less than 4.7%. The optical probe combined with multiple detection methods showed good practical significance and application prospects.
2021, 49(5): 768-778
doi: 10.19756/j.issn.0253-3820.201416
Abstract:
The inclusion compound (SOP/PP6A) of natural medicine sophocarpine (SOP) and water-soluble phosphate salt pillar[6]arene (PP6A) was prepared by saturated aqueous solution method. The host-guest complex properties of SOP and PP6A and their stoichiometric ratio were studied by fluorescence spectroscopy. The SOP/PP6A inclusion complex was characterized by scanning electron microscope (SEM), infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD) and thermos gravimetry (TG), and the nuclear magnetic resonance (1H NMR, 2D NMR), semi-empirical molecular orbital method and molecular docking speculated the possible inclusion mode of SOP/PP6A inclusion complex. Fluorescence spectroscopy showed that there was a strong host-guest interaction between the guest molecule SOP and the host-guest macrocyclic PP6A. The host-guest complex constant of 3360 L/mol was obtained by the nonlinear least squares curve fitting method. The equimolar continuous change method showed that the host-guest stoichiometric ratio was 1:1. SEM, FT-IR and XRD analysis tests indicated the successful preparation of the inclusion compound. TG analysis showed that the thermal stability of SOP was improved after the formation of the inclusion compound. 1H NMR and 2D NMR revealed that SOP entered the cavity of PP6A. The semi-empirical molecular orbital method and molecular docking calculations showed that PP6A was a good host for SOP. The host-guest space matching was high, but there was no hydrogen bond formation between the host and guest, and the driving force for the formation of clathrate was mainly hydrophobic. This study provided a selective idea for the research of new drug preparations of natural drug molecule SOP.
The inclusion compound (SOP/PP6A) of natural medicine sophocarpine (SOP) and water-soluble phosphate salt pillar[6]arene (PP6A) was prepared by saturated aqueous solution method. The host-guest complex properties of SOP and PP6A and their stoichiometric ratio were studied by fluorescence spectroscopy. The SOP/PP6A inclusion complex was characterized by scanning electron microscope (SEM), infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD) and thermos gravimetry (TG), and the nuclear magnetic resonance (1H NMR, 2D NMR), semi-empirical molecular orbital method and molecular docking speculated the possible inclusion mode of SOP/PP6A inclusion complex. Fluorescence spectroscopy showed that there was a strong host-guest interaction between the guest molecule SOP and the host-guest macrocyclic PP6A. The host-guest complex constant of 3360 L/mol was obtained by the nonlinear least squares curve fitting method. The equimolar continuous change method showed that the host-guest stoichiometric ratio was 1:1. SEM, FT-IR and XRD analysis tests indicated the successful preparation of the inclusion compound. TG analysis showed that the thermal stability of SOP was improved after the formation of the inclusion compound. 1H NMR and 2D NMR revealed that SOP entered the cavity of PP6A. The semi-empirical molecular orbital method and molecular docking calculations showed that PP6A was a good host for SOP. The host-guest space matching was high, but there was no hydrogen bond formation between the host and guest, and the driving force for the formation of clathrate was mainly hydrophobic. This study provided a selective idea for the research of new drug preparations of natural drug molecule SOP.
2021, 49(5): 779-788
doi: 10.19756/j.issn.0253-3820.201583
Abstract:
Bushen Zhuanggu Decoctions (BSZGD) is an effective prescription in the treatment of osteoporosis (OP) caused by testosterone deficiency, but the active ingredients for promoting testosterone synthesis are still unclear. The present study aims to reveal the active compounds of BSZGD for promoting testosterone synthesis by using 1H NMR-based metabolomics and molecular docking methods. After 24 h of administration, BSZGD and its membrane fractions could effectively improve the content of testosterone in the supernatant of Mouse Leydig cells (TM3 cells) induced by hydrogen peroxide. On the basis of medicinal materials, reference materials, literature reports and mass spectrometry data, a total of 27 kinds of chemical composites in the active fractions of BSZGD were identified by ultra-high performance liquid chromatography-quadrupole time-of-flight (RRLC-Q-TOF-MS) technique. 1H NMR metabolomics technology was used to reveal the differential metabolites of hydrogen peroxide-induced TM3 cells after the active fraction was given. A total of 41 metabolites were identified by 1H NMR-based metabolomics, of which 33 differential metabolites were found. Testosterone 17-β-dehydrogenase (17β-HSD) as the common metabolic targets of different metabolites and testosterone synthesis was identified using MetScape analysis. KEGG analysis showed that competitive inhibitors of the key protein kinase1 (ALPK1) could activate 17β-HSD and promote the synthesis of testosterone. Fourteen compounds were identified as potential active ingredients in BZGD for promoting testosterone synthesis by molecular docking technique. These results provided further evidence of BSZGD for promoting testosterone synthesis and were beneficial for its clinical application. The potential target and active components found in this study may provide valuable information for further studying the material basis of BSZGD. In addition, this work provided new insights for revealing the active ingredients of complex herbal preparations.
Bushen Zhuanggu Decoctions (BSZGD) is an effective prescription in the treatment of osteoporosis (OP) caused by testosterone deficiency, but the active ingredients for promoting testosterone synthesis are still unclear. The present study aims to reveal the active compounds of BSZGD for promoting testosterone synthesis by using 1H NMR-based metabolomics and molecular docking methods. After 24 h of administration, BSZGD and its membrane fractions could effectively improve the content of testosterone in the supernatant of Mouse Leydig cells (TM3 cells) induced by hydrogen peroxide. On the basis of medicinal materials, reference materials, literature reports and mass spectrometry data, a total of 27 kinds of chemical composites in the active fractions of BSZGD were identified by ultra-high performance liquid chromatography-quadrupole time-of-flight (RRLC-Q-TOF-MS) technique. 1H NMR metabolomics technology was used to reveal the differential metabolites of hydrogen peroxide-induced TM3 cells after the active fraction was given. A total of 41 metabolites were identified by 1H NMR-based metabolomics, of which 33 differential metabolites were found. Testosterone 17-β-dehydrogenase (17β-HSD) as the common metabolic targets of different metabolites and testosterone synthesis was identified using MetScape analysis. KEGG analysis showed that competitive inhibitors of the key protein kinase1 (ALPK1) could activate 17β-HSD and promote the synthesis of testosterone. Fourteen compounds were identified as potential active ingredients in BZGD for promoting testosterone synthesis by molecular docking technique. These results provided further evidence of BSZGD for promoting testosterone synthesis and were beneficial for its clinical application. The potential target and active components found in this study may provide valuable information for further studying the material basis of BSZGD. In addition, this work provided new insights for revealing the active ingredients of complex herbal preparations.
2021, 49(5): 789-797
doi: 10.19756/j.issn.0253-3820.201693
Abstract:
The metal-organic framework material of MIL-101(Fe) with H2O2 mimicking enzyme activity was synthesized by a typical hydrothermal method. MIL-101(Fe) and cardiac troponin I antibody (anti-cTnI) were then successively immobilized on the surface of glassy carbon electrode that was pre-modified with amino-modified graphene (NH2-GR) through the covalent bonding. Thus, a novel MIL-101(Fe)/NH2-GR-based electrochemical sensing interface for cTnI was constructed. Electrochemical experiments showed that the immunoreaction between anti-cTnI and target cTnI on the sensing interface significantly suppressed the electrocatalytic activity of electrode-confined MIL-101(Fe) to H2O2, realizing the label-free analysis of cTnI. Under the optimal conditions, the catalytic current difference (ΔI) and the negative logarithm of the cTnI concentration (-lgCcTnI) showed a good linear relationship in the concentration range of 10 fg/mL-0.1 μg/mL, and the detection limit was 3.1 fg/mL (S/N=3). The constructed sensor was applicable for detection of cTnI in actual human serum samples, and the recoveries were 96.0%-103.0%. The sensor exhibited good selectivity and reproducibility.
The metal-organic framework material of MIL-101(Fe) with H2O2 mimicking enzyme activity was synthesized by a typical hydrothermal method. MIL-101(Fe) and cardiac troponin I antibody (anti-cTnI) were then successively immobilized on the surface of glassy carbon electrode that was pre-modified with amino-modified graphene (NH2-GR) through the covalent bonding. Thus, a novel MIL-101(Fe)/NH2-GR-based electrochemical sensing interface for cTnI was constructed. Electrochemical experiments showed that the immunoreaction between anti-cTnI and target cTnI on the sensing interface significantly suppressed the electrocatalytic activity of electrode-confined MIL-101(Fe) to H2O2, realizing the label-free analysis of cTnI. Under the optimal conditions, the catalytic current difference (ΔI) and the negative logarithm of the cTnI concentration (-lgCcTnI) showed a good linear relationship in the concentration range of 10 fg/mL-0.1 μg/mL, and the detection limit was 3.1 fg/mL (S/N=3). The constructed sensor was applicable for detection of cTnI in actual human serum samples, and the recoveries were 96.0%-103.0%. The sensor exhibited good selectivity and reproducibility.
2021, 49(5): 798-808
doi: 10.19756/j.issn.0253-3820.201548
Abstract:
A new strategy by combining graphite phase carbon nitride/non-integral bismuth oxychloride/bismuth oxybromide (g-C3N4/BiOCl0.5Br0.5) heterojunction and the plasma resonance effect of gold nanoparticles (AuNPs) was used to construct a novel AuNPs/g-C3N4/BiOCl0.5Br0.5/ITO sensitized photoelectrochemical sensors for rapid and sensitive detection of the plant hormone 2-chloroethyl phosphate (ETH). The morphology of the as-prepared materials and characteristics of electrode film was characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and the photoelectrochemical response of the sensor to ETH was studied via electrochemical impedance spectroscopy (EIS) and current-time curve (i-t) methods. Density functional theory (DFT) was used to calculate the charge density of atoms in the g-C3N4/BiOCl0.5Br0.5 heterojunction, the electronic transition mechanism was analyzed, and the sensor's sensitization mechanism was further proposed. Under the optimal conditions, ETH concentration had a good linear relationship with photocurrent in the range of 20.00 nmol/L-63.00 μmol/L. The AuNPs/g-C3N4/BiOCl0.5Br0.5/ITO sensor exhibited high stability and high reproducibility. This study provided a feasible strategy for rapid and efficient detection of ETH, as well as a new sensing platform for detection of other plant hormones.
A new strategy by combining graphite phase carbon nitride/non-integral bismuth oxychloride/bismuth oxybromide (g-C3N4/BiOCl0.5Br0.5) heterojunction and the plasma resonance effect of gold nanoparticles (AuNPs) was used to construct a novel AuNPs/g-C3N4/BiOCl0.5Br0.5/ITO sensitized photoelectrochemical sensors for rapid and sensitive detection of the plant hormone 2-chloroethyl phosphate (ETH). The morphology of the as-prepared materials and characteristics of electrode film was characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and the photoelectrochemical response of the sensor to ETH was studied via electrochemical impedance spectroscopy (EIS) and current-time curve (i-t) methods. Density functional theory (DFT) was used to calculate the charge density of atoms in the g-C3N4/BiOCl0.5Br0.5 heterojunction, the electronic transition mechanism was analyzed, and the sensor's sensitization mechanism was further proposed. Under the optimal conditions, ETH concentration had a good linear relationship with photocurrent in the range of 20.00 nmol/L-63.00 μmol/L. The AuNPs/g-C3N4/BiOCl0.5Br0.5/ITO sensor exhibited high stability and high reproducibility. This study provided a feasible strategy for rapid and efficient detection of ETH, as well as a new sensing platform for detection of other plant hormones.
2021, 49(5): 809-819
doi: 10.19756/j.issn.0253-3820.201560
Abstract:
Glutamic acid and histidine functionalized graphene quantum dots (Glu-GQD-His) were synthesized by pyrolysis of the mixture of citric acid, glutamic acid and histidine. The resulting Glu-GQD-His was composed of 2-3 layers of graphene sheets with an average size of (3.85±0.15) nm and rich functional groups. Glu-GQD-His could offer a strong blue fluorescence emission under visible light excitation, which was higher than that of graphene quantum dot (GQD) made via pyrolysis of citric acid. The results demonstrated that the introduction of glutamic acid and histidine could improve the optical properties. As an optical probe, Glu-GQD-His was of a low toxicity and could be used for cell fluorescence imaging. As an artificial peroxidase, Glu-GQD-His could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine with H2O2 to produce corresponding blue oxidation product. The Michaelis constant (Km) reached 1.110 mmol/L, which was significantly lower than that of horseradish peroxidase (3.702 mmol/L) and GQD (1.443 mmol/L). This verified that Glu-GQD-His had a better catalytic activity. Based on the above catalytic reaction, the colorimetric method for determination of H2O2 was established. In the concentration range of 0.001-1.0 mmol/L, the absorbance of blue oxidation products would increase linearly with increasing H2O2 concentration. The detection limit of the method was 0.4 μmol/L. The as-proposed method provided better sensitivity and selectivity compared with the present analytical methods, and was successfully applied to detection of H2O2 inside and outside tumor cells.
Glutamic acid and histidine functionalized graphene quantum dots (Glu-GQD-His) were synthesized by pyrolysis of the mixture of citric acid, glutamic acid and histidine. The resulting Glu-GQD-His was composed of 2-3 layers of graphene sheets with an average size of (3.85±0.15) nm and rich functional groups. Glu-GQD-His could offer a strong blue fluorescence emission under visible light excitation, which was higher than that of graphene quantum dot (GQD) made via pyrolysis of citric acid. The results demonstrated that the introduction of glutamic acid and histidine could improve the optical properties. As an optical probe, Glu-GQD-His was of a low toxicity and could be used for cell fluorescence imaging. As an artificial peroxidase, Glu-GQD-His could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine with H2O2 to produce corresponding blue oxidation product. The Michaelis constant (Km) reached 1.110 mmol/L, which was significantly lower than that of horseradish peroxidase (3.702 mmol/L) and GQD (1.443 mmol/L). This verified that Glu-GQD-His had a better catalytic activity. Based on the above catalytic reaction, the colorimetric method for determination of H2O2 was established. In the concentration range of 0.001-1.0 mmol/L, the absorbance of blue oxidation products would increase linearly with increasing H2O2 concentration. The detection limit of the method was 0.4 μmol/L. The as-proposed method provided better sensitivity and selectivity compared with the present analytical methods, and was successfully applied to detection of H2O2 inside and outside tumor cells.
2021, 49(5): 820-829
doi: 10.19756/j.issn.0253-3820.201540
Abstract:
Data-independent acquisition (DIA)-based quantitative proteomics has been widely used in life science and clinical proteomics research. In this study, the quantitative performance of three most common Orbitrap mass spectrometers (Q Exactive Plus, Q Exative HF-X and Orbitrap Fusion Lumos) used in proteomics were compared. A corresponding DIA method was established for each mass spectrometer and three groups of samples including commercial Hela digested peptides as QC sample, high abundant proteins depleted plasma samples and mixture samples of plasma and yeast at fixed ratios were designed to evaluate the proteome coverage, quantitative reproducibility, accuracy and precision. In QC sample, 34000-37000 peptides and 4400 proteins were quantified by each mass spectrometer, 81% of the peptides and 96% of the proteins were quantified by all mass spectrometers, and the median coefficient of variations of protein intensities were below 5%. In depleted plasma samples, each mass spectrometer quantified 4400-5100 peptides and 550-620 proteins with a 60-min gradient, 64% of the peptides and 80% of the proteins were quantified by each mass spectrometer, and the median coefficient of variations of protein intensities were below 5%. In a mixed sample with known ratios, each mass spectrometer quantified 260-297 plasma proteins and 2210-2436 yeast proteins. The precision and number of differential proteins were comparable. Due to the difference in the hardware design of three mass spectrometers, quantification was affected by the batch effect when combined analysis was performed. After batch effect normalization, the quantitative performance was equivalent to that of each mass spectrometer. These results showed that the quantitative performance of DIA on three mass spectrometers was comparable and provided reference for large scale DIA quantification with multiple Orbitraps.
Data-independent acquisition (DIA)-based quantitative proteomics has been widely used in life science and clinical proteomics research. In this study, the quantitative performance of three most common Orbitrap mass spectrometers (Q Exactive Plus, Q Exative HF-X and Orbitrap Fusion Lumos) used in proteomics were compared. A corresponding DIA method was established for each mass spectrometer and three groups of samples including commercial Hela digested peptides as QC sample, high abundant proteins depleted plasma samples and mixture samples of plasma and yeast at fixed ratios were designed to evaluate the proteome coverage, quantitative reproducibility, accuracy and precision. In QC sample, 34000-37000 peptides and 4400 proteins were quantified by each mass spectrometer, 81% of the peptides and 96% of the proteins were quantified by all mass spectrometers, and the median coefficient of variations of protein intensities were below 5%. In depleted plasma samples, each mass spectrometer quantified 4400-5100 peptides and 550-620 proteins with a 60-min gradient, 64% of the peptides and 80% of the proteins were quantified by each mass spectrometer, and the median coefficient of variations of protein intensities were below 5%. In a mixed sample with known ratios, each mass spectrometer quantified 260-297 plasma proteins and 2210-2436 yeast proteins. The precision and number of differential proteins were comparable. Due to the difference in the hardware design of three mass spectrometers, quantification was affected by the batch effect when combined analysis was performed. After batch effect normalization, the quantitative performance was equivalent to that of each mass spectrometer. These results showed that the quantitative performance of DIA on three mass spectrometers was comparable and provided reference for large scale DIA quantification with multiple Orbitraps.
2021, 49(5): 830-838
doi: 10.19756/j.issn.0253-3820.201656
Abstract:
Based on QuEChERS and with self-synthesized novel mesoporous materials (SBA-15-C18) as a purification agent, a method for determination of 10 kinds of pesticide residues in tea matrix by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed. With the action of template, SBA-15 was prepared by solution chemical reaction method, and SBA-15-C18 was then prepared by in-situ co-condensation method on the surface of SBA-15 with octadecyl silane coupling agent. And they were characterized by scanning electron microscopy and infrared spectroscopy. The sample was extracted with acetonitrile, purified by SBA-15-C18, nano-zirconia and multi-wall carbon nanotube tubes, and quantitatively analyzed by external standard method of UPLC-MS/MS. The results showed that SBA-15-C18 had a two-dimensional through-hole structure, uniform particle size and a cylindrical curved shape, with average particle size of 240-340 nm. In the concentration range of 0.0025-0.5 mg/L, the standard solution concentration of 10 kinds of target pesticides in tea matrix showed a good linear relationship with the corresponding chromatographic response value, and the correlation coefficients were between 0.9978 and 0.9999. The average recoveries of the 10 kinds of pesticides at three addition levels of 0.01, 0.1 and 20 mg/kg were between 72% and 111%, and RSDs were 1.0%-6.9%. The limits of detection of 10 kinds of pesticides in tea matrix were 0.1-0.3 μg/kg, and the limits of quantification were 0.2-0.9 μg/kg. The method was applied to monitoring of the samples of the main tea varieties. The method had many advantages such as high sensitivity, strong versatility, high accuracy, good stability and easy operation, and was suitable for detection of pesticide residues in tea.
Based on QuEChERS and with self-synthesized novel mesoporous materials (SBA-15-C18) as a purification agent, a method for determination of 10 kinds of pesticide residues in tea matrix by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed. With the action of template, SBA-15 was prepared by solution chemical reaction method, and SBA-15-C18 was then prepared by in-situ co-condensation method on the surface of SBA-15 with octadecyl silane coupling agent. And they were characterized by scanning electron microscopy and infrared spectroscopy. The sample was extracted with acetonitrile, purified by SBA-15-C18, nano-zirconia and multi-wall carbon nanotube tubes, and quantitatively analyzed by external standard method of UPLC-MS/MS. The results showed that SBA-15-C18 had a two-dimensional through-hole structure, uniform particle size and a cylindrical curved shape, with average particle size of 240-340 nm. In the concentration range of 0.0025-0.5 mg/L, the standard solution concentration of 10 kinds of target pesticides in tea matrix showed a good linear relationship with the corresponding chromatographic response value, and the correlation coefficients were between 0.9978 and 0.9999. The average recoveries of the 10 kinds of pesticides at three addition levels of 0.01, 0.1 and 20 mg/kg were between 72% and 111%, and RSDs were 1.0%-6.9%. The limits of detection of 10 kinds of pesticides in tea matrix were 0.1-0.3 μg/kg, and the limits of quantification were 0.2-0.9 μg/kg. The method was applied to monitoring of the samples of the main tea varieties. The method had many advantages such as high sensitivity, strong versatility, high accuracy, good stability and easy operation, and was suitable for detection of pesticide residues in tea.
2021, 49(5): 839-846
doi: 10.19756/j.issn.0253-3820.211035
Abstract:
The heavy metal pollution of peat bog wetland in different succession stages is different, and the determination and evaluation of heavy metals in soil are conducive to the management and protection of natural wetland. In this work, inductively coupled plasma mass spectrometer, inductively coupled plasmon emission spectrometer and atomic fluorescence spectrometry were used to determine the ten heavy metals (Cu, Zn, Pb, Ni, Cr, Mn, As, Se, Cd and Hg) in the soil of three typical peat bog wetlands (Gushantun Wetland, Jinchuan Wetland and Hanlongwan Wetland) with different succession stages in the Longwan Nature Reserve of Tonghua City, Jilin Province, China. The geo-accumulation index and potential ecological risk index were used to evaluate the heavy metal pollution in wetland, and the source of heavy metals was explored through correlation analysis and principal component analysis. The results showed that the contents of Cu, Hg, Ni, Cr, Mn and As in the soil of Jinchuan Wetland with the longer succession time were the highest. The contents of Zn, Pb, Cd and Se in the soil of Hanlongwan Wetland with the shortest succession time were the highest. The average contents of Cd and Hg in the three wetland soils exceeded the environmental background value. The Cd and Hg had the highest contributions to ecological risk of wetland soil, and the contribution rate could reach more than 90%. Among them, the pollution level of Cd in Hanlongwan Wetland was the highest, which was moderately to strongly polluted. The Hg had the highest pollution level in the Jinchuan Wetland, which was unpolluted to moderately polluted. The potential ecological risk level of the Hanlongwan Wetland was the highest. The sources of Zn, Pb, Cd and Hg were different from Cu and Mn, which might be affected by the factors such as agricultural irrigation, domestic sewage discharge, transportation, natural settlement, etc.
The heavy metal pollution of peat bog wetland in different succession stages is different, and the determination and evaluation of heavy metals in soil are conducive to the management and protection of natural wetland. In this work, inductively coupled plasma mass spectrometer, inductively coupled plasmon emission spectrometer and atomic fluorescence spectrometry were used to determine the ten heavy metals (Cu, Zn, Pb, Ni, Cr, Mn, As, Se, Cd and Hg) in the soil of three typical peat bog wetlands (Gushantun Wetland, Jinchuan Wetland and Hanlongwan Wetland) with different succession stages in the Longwan Nature Reserve of Tonghua City, Jilin Province, China. The geo-accumulation index and potential ecological risk index were used to evaluate the heavy metal pollution in wetland, and the source of heavy metals was explored through correlation analysis and principal component analysis. The results showed that the contents of Cu, Hg, Ni, Cr, Mn and As in the soil of Jinchuan Wetland with the longer succession time were the highest. The contents of Zn, Pb, Cd and Se in the soil of Hanlongwan Wetland with the shortest succession time were the highest. The average contents of Cd and Hg in the three wetland soils exceeded the environmental background value. The Cd and Hg had the highest contributions to ecological risk of wetland soil, and the contribution rate could reach more than 90%. Among them, the pollution level of Cd in Hanlongwan Wetland was the highest, which was moderately to strongly polluted. The Hg had the highest pollution level in the Jinchuan Wetland, which was unpolluted to moderately polluted. The potential ecological risk level of the Hanlongwan Wetland was the highest. The sources of Zn, Pb, Cd and Hg were different from Cu and Mn, which might be affected by the factors such as agricultural irrigation, domestic sewage discharge, transportation, natural settlement, etc.
