最新刊期
卷 37 ， 期 9 ， 2018
- 摘要：A comprehensive analytical method was developed for the simultaneous determination of nine uric acid regulation drugs illegally added in Chinese traditional patent medicine and health-care food by liquid chromatography-tandem mass spectrometry（LC-MS/MS）.The sample was dipersed with water，and the analytes were ultrasonically extracted using vortex mixer with acetonitrile.The chromatographic separation was performed on a Poroshell 120 Bonus-RP chromatographic column（100 mm×2.1 mm，2.7 μm），with 0.1%（by volume）acetic acid aqueous solution containing 5 mmol/L ammonium formate and acetonitrile as mobile phases by gradient elution.The qualitative and quantitative analyses were performed by electrospray ionization mass spectrometry in positive mode under multiple reaction monitoring（MRM）mode.Results showed that the calibration curves for nine drugs were linear in the corresponding concentration ranges with their correlation coefficients larger than 0.99.The average recoveries for 9 drugs at three spiked levels ranged from 79.2% to 108%，with relative standard deviations（RSDs）of 1.2%-12%.The limits of detection（LOD）and quantitation（LOQ）were in the ranges of 0.03-0.6 mg/kg and 0.1-2.0 mg/kg，respectively.The established method is simple，rapid，sensitive，accurate and reliable，and is suitable for the determination of nine uric acid regulation drugs illegally added in Chinese traditional patent medicine and health-care food.关键词：liquid chromatography-tandem mass spectrometry（LC-MS/MS）;Chinese traditional patent medicine;health-care food;uric acid regulation drug;illegally added
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发布时间： - 摘要：A method of ultra high performance liquid chromatography（UPLC） was developed for the simultaneous determination of 10 biogenic amine components in Cervi Curnu Pantotrichum（CCP），and the differences among the biogenic amines in Cervi Curnu Pantotrichum（CCP） processed with different methods were compared.Biogenic amines in the CCP samples were extracted with 0.4 mol/L perchloric acid，derivatized with dansyl chloride（DNCSI），then determinated by UPLC.The optimal conditions were follows:chromatographic column:ACQUITY UPLC@BEH C18（2.1 mm×100 mm，1.7 μm），mobile phase:acetonitrile-water，column temperature:35 ℃，flow rate:0.4 mL/min，detection wavelength:217 nm.The calibration curves for 10 biogenic amines were linear in a certain concentration with their correlation coefficients of 0.997 8-0.999 9 and the detection limits of 10.87-19.63 μg/L.The recoveries ranged from 71.6% to 101%.The total biogenic amines in wax slice，powder slice，gauze slice and bone slice for the boiled CCP were 312.33，176.88，105.31 and 55.674 mg/kg，respectively，and that for the freeze-dried CCP were 291.77，152.85，114.49 and 74.73 mg/kg，respectively.Likewise，those in these 4 sections for the blood-drained CCP and the blood-filled CCP were 357.07，226.26，125.18 and 77.74 mg/kg，and 343.42，216.72，125.15 and 76.16 mg/kg，respectively.As a whole，the total biogenic amines in freeze-dried CCP were higher than that in boiled CCP，while those in blood-drained CCP were higher than that in blood-filled CCP.The total biogenic amines in CCP with 4 processing methods showed a trend of decline from wax slice downward to bone slice，and the differences in different sections were all significant（P<0.05）.关键词：Cervi Curnu Pantotrichum;biogenic amines;processing methods;sections;comparative analysis;ultra high performance liquid chromatography（UPLC）
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发布时间： - 摘要：A gas chromatography-tandem mass spectrometric（GC-MS/MS）method was developed for the determination of 9 volatile perfluorinated compounds precursors including perfluorinated fatty alcohol，perfluorinated fatty alcohol acrylate and perfluorosulfonamide fatty alcohol，using 3% acetic acid，10% alcohol，50% alcohol，and olive oil as food simulants according to（EU） 2017/752.The water-based and olive oil simulants were extracted with dichloromethane and acetonitrile，respectively.The volatile perfluorinated compounds precursors were separated on a DB-5MS（30 m×0.25 mm×0.25 μm）column，and analyzed under multiple reaction monitoring mode.The cailbration curves for 9 analytes were linear in the range of 5-500 μg/L，with the quantitation limits of 3.3-4.4 μg/L for 3% acetic acid，3.5-4.2 μg/L for 10% alcohol，3.3-4.9 μg/L for 50% alcohol and 4.2-5.1 ng/g for olive oil，respectively.The spiked recoveries for the samples ranged from 85.0% to 115% with the relative standard deviations（RSDs）not more than 7.8%.This method was fast，precise and convenient，and was appropriate for the determination of 9 perfluorinated compounds precursors in food-contact paper based materials.关键词：food-contact paper based materials;fluorinated compounds;precursors;migration;liquid-liquid extraction;gas chromatography-tandem mass spectrometry（GC-MS/MS）
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发布时间： - 摘要：A method of liquid chromatograph-tandem mass spectrometry（LC-MS/MS） with QuEChERS pretreatment was developed for the determination of seven kinds of mycotoxins，including aflatoxin B1（AFB1），aflatoxin B2（AFB2），aflatoxin G1（AFG1），aflatoxin G2（AFG2），ochratoxin A（OTA），ochratoxin B（OTB） and ochratoxin C（OTC） in foods.The samples were diluted with formic acid-acetonitrile （10∶90，by volume），and then purified by QuEChERS using a scavenging agent（1.2 g MgSO4+0.25 g C18+0.4 g PSA+0.25 g Al-N） after centrifugation.The detection on the analytes was performed by LC-MS/MS in positive ionization under multiple-reaction monitoring（MRM） mode.There existed good linearities for seven mycotoxins in their respective concentraction ranges with correlation coeffieionts not less than 0.999.The limits of quantitation（LOQs） were in the range of 0.25-5.0 μg/kg，and the average recoveries for seven mycotoxins were between 71.5% and 119% with the relative standard deviations（RSDs，n=6） of 1.1%-7.7%.The developed method was simple，sensitive and reproducible，and was suitable for the determination of these mycotoxins in foods in batch production.关键词：QuEChERS;mycotoxin;ochratoxins;aflatoxins;LC-MS/MS
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发布时间： - 摘要：A high-sensitive electrochemical immunosensor was prepared by immobilizing anti-HupA monoclonal antibody onto the glassy carbon electrode modified with a reduced graphene oxide/chitosan composite membrane.And an electrochemical immunosensor for the detection of huperzine A（HupA）was established as the antigen-anibody reaction could block the electron transfer of［Fe（CN）6］3-/4- redox system.The electrochemical behavior of HupA in［Fe（CN）6］3-/4- redox system was investigated by cyclic voltammetry（CV），electrochemical impedance spectroscopy（EIS）and differential pulse voltammetry（DPV）.Under the optimized conditions, there existed a good linearity between HupA concentration logarithm and the difference of peak current in the assay system of 15 mmol/L K3Fe（CN）6+0.1 mol/L KCl+0.1 mol/L PBS（pH 6.5） in range of 1.0×10-13-1.0×10-10 mol/L with a correlation coefficient（r）of 1.000 0.The detection limit was 3.0×10-14 mol/L, and the recoveries were in the range of 99.4%-102%.With the characteristics of strong specificity, high sensitivity, simple operation and environmental protection, this method could be used for the rapid detection of huperzine A in natural herbs.关键词：graphene;chitosan;huperzine A;electrochemical immunosensor;differential pulse voltammetry（DPV）
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发布时间： - 摘要：The interaction between tetrasulfonated zinc phthalocyanine（ZnPcPS4） and albumin（BSA and HSA） was studied by fluorescence spectroscopy.The results showed that albumin had a significant effect on the existing state of ZnPcPS4,and there was a strong interaction between ZnPcPS4 and albumin with a binding constant about 106 orders of magnitude.The competitive binding experiment showed that the binding site for the interaction was mainly located at subdomain IB of BSA.The ZnPcPS4-BSA and ZnPcPS4-HSA complexes were further prepared by a molar ratio of phthalocyanine to albumin about 1∶1.Spectroscopic studies showed that the complexes exhibited a more prominent monomer absorption peak than free phthalocyanine,and the Q-band maximum had a red shift from 692 nm to 696 nm,which was beneficial to photodynamic therapy.Photodynamic anticancer activity test showed that ZnPcPS4-BSA had a high photodynamic anticancer activity with an IC50 value as low as 1.68 μmol/L,which was significantly higher than that of the corresponding free phthalocyanine ZnPcPS4（IC50=2.73 μmol/L）.This could be attributed to the fact that the complexes have a higher cellular uptake toward cancer.关键词：sulfonated phthalocyanine;albumin;photodynamic therapy;spectroscopic properties
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发布时间： - 摘要：A method of high speed counter-current chromatography was developed for the separation and preparation of three active compounds，phenolic glycerol glycosides from the bulbs of Lilium species used as Chinese tradition medicine.The ethylacetate-n-butanol-water(0.5% acetic acid，3∶1.5∶5，by volume) was used as a two-phase solvent system，in which the upper phase was stationary phase and the lower phase was mobile phase for the isolation of the compounds from the extract of Lilium brownii F.E.Brown var.viridulum Baker by high speed counter-current chromatography(HSCCC).Additionally，the antioxidant activities on free radical scavenging and lipid peroxidation，and the effects on α-amylase activity were evaluated.Results showed that 4.2 mg of compound 1(96.2%，purity)，2.3 mg of compound 2(95.1%) and 5.8 mg of compound 3(98.8%) were obtained from the 250 mg extract by one-step using high-performance liquid chromatography(HPLC).The chemical structures of the compound 1-3 were identified as regaloside A，acetylregaloside C and regaloside B，respectively by mass spectrometry(MS) and nuclear magnetic resonance imaging(NMR).Biological activity test showed that acetylregaloside C exhibited a strong capacity scavenging DPPH and inhibiting lipid peroxidation，while regaloside A and regaloside B had weak capacity scavenging DPPH and definite inhibitory effects on lipid peroxidation.The antioxidant effects of the compounds were as follows:acetylregaloside C>regaloside A≈regaloside B.The promoting effects of the compounds on the activity of α-amylase were different in different concentrations，but no significant difference existed among the compounds关键词：separation;Lilium;phenolic glycerol glycosides;high speed counter-current chromatography(HSCCC);activities
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发布时间： - 摘要：The contents of five kinds of arsenic speciations in sludge，i.e.As(Ⅲ)，monomethylarsenic(MMA)，dimethylarsenic(DMA)，As(Ⅴ) and arsenicbetaine(AsB) were determined by liquid chromatography hydride generation atomic fluorescence spectrometry(LC-AFS) with UV online digestion.The content of total arsenic(T-As) was determined by inductively coupled plasma optical emission spectrometry(ICP-OES).Under the optimized conditions for liquid phase separation and post column derivatization，the five arsenic speciations were separated and determined in 10 min with 15 mmol/L (NH4)2HPO4 as mobile phase at pH 6.0，5%(by volume) HCl as carrier and 5 g/L NaOH and 10 g/L KBH4 as reducing agents.In this experiment，the T-As was close to the sum of five arsenic speciations，and the relative standard deviations for them each other were less than 5%.The detection limits for As(Ⅲ)，As(Ⅴ)，MMA，DMA，AsB and T-As were 0.3，2.1，1.4，1.1，0.7 and 0.8 μg/L，respectively.The correlation coefficients for five arsenic speciations and T-As were larger than 0.999 in the linear range.With the advantages of convenient pretreatment，accuracy and reproducibility，the proposed method could provide a technical basis for the analysis of arsenic speciation in sludge.关键词：environmental hazards;sludge;arsenic;speciation analysis;liquid chromatography-atomic fluorescent spectrometry(LC-AFS);ICP-OES
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发布时间： - 摘要：The carbon dots（CDs）were synthesized by one step hydrothermal method using the plant soot as raw material.Effects of plant soot amount，concentration of H2O2 solution，pH value of reaction solution，reaction time and temperature were also discussed.The maximum excitation and emission wavelengths of CDs were 340 nm and 450 nm，respectively，and no red shift was observed with the increase of excitation wavelength.The Fourier-transform infrared（FTIR） spectra characterization demonstrated that CDs contained lots of —COOH and —OH groups on their surface.The synthesized CDs could be used as a tool for the detection on chlortoluron as their fluorescent intensity could be selectively quenched by chlortoluron.The linear range of the method for chlortoluron was 0.15-3.15 mg·L-1，with a correlation coefficient（r2） of 0.999 3 and a detected limit of 0.05 mg·L-1.The proposed method was applied in the detection of chlortoluron in irrigation water samples with recoveries of 93.3%-112% and RSDs not more than 4.9%.Meanwhile，the influences of pesticides with similar structures to chlortoluron and common ions on the system were investigated，and the quenching mechanism for chlortoluron toward CDs was also discussed.关键词：carbon dots;plant soot;hydrothermal method;chlortoluron;fluorescence
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发布时间： - 摘要：A water-soluble molecular fluorescence probe，dimethyl curcumin（ASC-J9）liposome was developed for the recognition of Fe3+，Fe2+ and Cu2+ through fluorescence quenching.The ASC-J9 liposome was prepared by thin-film dispersion，which had a uniform particle size distribution with a particle size of 145.7 nm and a polymer dispersity index（PDI）of 0.361.The optimal fluorescence conditions obtained by conditional screening were as follows：ASC-J9 liposome concentration：5.0×10-5 mol/L，balance time：5 min，temperature：25 ℃.The binding modes of ASC-J9 liposome with Fe3+，Cu2+ and Fe2+ were achieved by Jobs plot and fluorescence titration.Results showed that the binding ratios for the probe to Fe3+ and Cu2+ were both 1∶1，while that for the probe to Fe2+ was 2∶1.The fluorescence quenching type was determined by Stern-Volmer plot as static quenching，and the association constants of KFe（Ⅲ），KFe（Ⅱ）and KCu（Ⅱ）were 9.63×104 L/mol，3.65×105 L/mol and 2.32×105 L/mol，respectively.With the advantages of rapid detection and high sensitivity，this method was applied in the identification of Fe3+，Fe2+ and Cu2+ ions in water samples.The calibration curves for Fe3+，Fe2+ and Cu2+ were 5.0×10-7 -3.0×10-5 mol/L，5.0×10-7 -1.75×10-5 mol/L and 5.0×10-7 -2.5×10-5 mol/L，with their limits of detection of 6.41×10-7 mol/L，3.28×10-7 mol/L and 5.08×10-7 mol/L，respectively.关键词：dimethyl curcumin（ASC-J9）;liposome;fluorescence probe;metal ion;water
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发布时间： - 摘要：Combined with magnetic solid phase extraction,a simple and rapid ion chromatographic method was established for the detection of glyphosate residues in soil samples.Experimental conditions such as extraction solvent,conditions of ion chromatography and purification material were also optimized.After extracted with water，the samples were precipitated with acetonitrile to eliminate the impurities，then purifed with Fe3O4 magnetic nanoparticles.The supernatant was separated on an IonPac AS11-HC column with 30 mmol/L KOH as the eluent，and a conductivity detector was used for the detection.Results showed that a good linearity was obtained in the range of 0.05-2.0 mg/L（r2 =0.999 7）.The limits of detection and quantitation for the analyte were 13 μg/L and 45 μg/L，respectively.The recoveries for the soil samples at spiked levels of 50，100 and 200 μg/L were between 83.2% and 94.5%，with the intra-day and inter-day RSDs of 1.9%-3.1% and 1.9%-3.7%，respectively.The method is simple，rapid，sensitive and reliable，and could fully meet the detection requirements in the national standard.关键词：ion chromatography;magnetic solid phase extraction;glyphosate;soil samples
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发布时间： - 摘要：An effective method of high-performance liquid chromatography（HPLC）was developed for the determination of imidazole，the harmful ingredient in cigarette additives based on pre-column derivatization with dansyl chloride（Dns-Cl）.The additive samples firstly underwent the treatment of a buffer of carbonate solution，followed by the pre-column derivatization with dansyl chloride，then the extraction with ethyl acetate，dryness，evaporation，dilution with acetonitrile and filteration，separation on a C18 column，elution with acetonitrile-water by gradient elation，and finally the detection with a fluorescence detector.The optimum derivatising conditions of imidazole with dansyl chloride are as follows:concentration of dansyl chloride:1 000 mg/L;temperature of reaction:45 ℃;pH of buffer solution:10.0;time of reaction:40 min. The imidazole derivative was quantified by the external standard method.There was a good linearity for the analyte in the range of 0.5-500 mg/L with a correlation coefficient of 0.999 5.The limits of detection of the method for imidazole derivative was 0.24 mg/kg，and the limits of quantitation was 0.80 mg/kg.The recoveries at three spiked levels ranged from 89.1% to 97.2% with RSDs not more than 7.5%.Results showed that the method was accurate and reliable，and was applicable to the determination of imidazole content in cigarette additives.关键词：pre-column derivatization;high-performance liquid chromatography（HPLC）;cigarette additives;imidazole;dansyl chloride
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发布时间： - 摘要：A novel peptide-based electrochemiluminescent（ECL）method for the determination of prostate-specific antigen（PSA）was developed based on the target-induced cleavage of homogeneous specific polypeptide with gold nanoparticles（AuNPs） to overcome drawbacks from probes directly immobilized on electrodes.A specific peptide CHSSKLQK was employed as a molecular recognition element，and ruthenium（Ⅱ）complexes（Ru1）were used as ECL emitting species.A site-specific enzymatic-cleavage-reaction-based biosensor using Ru1/peptide-conjugated gold nanoparticle complexes（AuNPs-peptide-Ru1）was developed.When PSA was added into the solution containing AuNPs-peptide-Ru1，PSA specifically recognized and cleaved the sequence of the peptides attached to the AuNPs.As a result，Ru1 were separated from the AuNPs and resulted in the increase of ECL intensity in the presence of co-reactant tripropylamine.Results showed that the increased ECL intensity was directly linear to the logarithm of PSA concentration in range of 5.0×10-12-1.0×10-9 g/mL with a detection limit of 2.0×10-12 g/mL.The method was applied in the detection of clinical serum samples，and the results were consistent with those obtained by CL method.With the advantages of high sensitivity and good reproducibility，this method provides a promising strategy for the sensitive detection on protease.关键词：electrochemiluminescence;Au nanoparticle;enzymatic cleavage reaction;prostate specific antigen（PSA）;homogeneous polypeptide cleavage
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发布时间： - 摘要：Based on high-throughput screening technology and inkjet printing，a rapid method was established for the analysis on photocatalytic efficiencies of photocatalysts with different proportions.In this experiment，a microreaction chip with thousands of independent reaction units was prepared by photolithography，and three metal elements of Ni，Cd and Zn were selected to dope into TiO2.Then a catalyst library including 900 different metal sulfides assembled TiO2 was established.Three high efficiency of photocatalytic materials with different ratios：（Ni0.28Cd0.32Zn0.40）SX/TiO2，（Ni0.43Cd0.29Zn0.28）SX/TiO2 and（Ni0.17Cd0.56Zn0.27）SX/TiO2 were quickly screened out on the basis of the fluorescence emitted by different microreaction units through once experimental reaction.In addition，the activities for three catalysts were verified by macro verification experiments，and a group of pure TiO2 degraded eosin solutions without load were compared.Results showed that the degradation rates for 3 catalysts were 94.2%，90.5% and 87.6%，respectively，while the pure TiO2 without load had the lowest degradation efficiency（41.3%）.The results showed that the as-prepared catalysts were of high efficiency in photocatalytic degradation on eosin solution.关键词：high-throughput screening technology;inkjet printing;TiO2;microreaction chip;photocatalysis
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发布时间： - 摘要：An isotope dilution/gas chromatography-inductively coupled plasma mass spectrometric（ID/GC-ICP-MS）method was developed for the separation and determination of trace of methylmercury（MeHg）in seawater after an automatic distillation.Results showed that the distillation pretreatment for the seawater samples could be completed in 45 min using an automatic distillation apparatus，and BrCl solution was very efficient in removing the MeHg residues in the distillation ware，which could result in the procedural blank lowering markedly.The artificial MeHg during the distillation process might be negligible if the total mercury mass concentration in the sample was lower than 1.0 μg·L-1.The spiked recoveries for MeHg in seawater ranged from 98.2% to 122%，with RSDs for MeHg in natural seawater and spiked seawater of 16% and 5.4%，respectively，and the detection limits were 0.009 ng·L-1.The method was applied in the analysis of MeHg in the surface seawater collected from Dalian Bay with average MeHg concentration of （0.103±0.036） ng·L-1，and it could meet the requirements for analysis of trace methylmercury in coastal water.关键词：gas chromatography-inductively coupled plasma mass spectrometry（GC-ICP-MS）;isotope dilution;seawater;methylmercury;automatic distillation apparatus
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发布时间： - 摘要：A novel Ru（phen）2+3-Ce（Ⅳ）-Ru3+ chemiluminescence（CL） method was developed for the determination of furosemide based on the phenomenon that in the presence of ruthenium（Ⅲ）（Ru3+）,furosemide could greatly enhance the CL intensity of tris-（1,10-phenanthroline） ruthenium（Ⅱ）（Ru（phen）2+3）-cerium（Ⅳ）（Ce（Ⅳ）） system.With the increase of Ru3+ concentration from 0 to 15 μmol/L,the CL intensity of the system was enhanced by one order of magnitude,and the sensitization of Ru3+ was very significant.The CL reaction conditions were optimized,and the optimum concentrations for Ru3+,Ru（phen）2+3,Ce（Ⅳ） and H2SO4 were 15 μmol/L,0.10 mmol/L,0.20 mmol/L and 15 mmol/L,respectively.Under the optimum conditions,the calibration curve was linear in the range of 5.0×10-9-2.0×10-6 mol/L with a detection limit of 3.8×10-9 mol/L.The proposed method had a wider linear range and lower detection limit than all other reported CL methods.The method was applied in the analysis of furosemide in furosemide tablets and furosemide injection with satisfactory results.Referring to the investigation of UV-spectra,the possible mechanism for CL reaction was proposed in this paper.关键词：furosemide;Ru3+;tris-（1,10-phenanthroline） ruthenium（Ⅱ）;chemiluminescence
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发布时间： - 摘要：A gas chromatography-triple quadrupole mass spectrometric(GC-MS/MS) method was established for the determination of alkyl phosphoric acids，metabolites of organophosphorus nerve agents in urine.The samples exposed to organophosphorus nerve agents were detected by MS/MS using chemical ion source(CI ) in negative ion mode under selected reaction monitoring(SRM) mode.Both quantification and confirmation ions were optimized for each of 5 alkyl phosphoric acids.5 alkyl phosphoric acids were simultaneously detected in 30 min.The calibration curves for the analytes were linear in the certain concentration ranges with the limits of detection(LOD) and quantitation(LOQ) of 0.1 μg/L and 0.5 μg/L，respectively.The intra-day and inter-day RSDs were in the range of 2.4%-4.3% and 2.5%-4.5%，respectively.The average recoveries were in the range of 97.3%-98.9% and the RSDs for the method repeatability were 5.3%-10%.With the advantages of excellent selectivity，accuracy，high sensitivity，specificity and good repeatability，the method is suitable for the qualitative and quantitative detections of alkyl phosphoric acids in urine samples exposed to organophosphorus nerve agents.关键词：gas chromatography-triple quadrupole mass spectrometry(GC-MS/MS);alkyl phosphoric acids;fluorinated derivatization;urine exposed to organophosphorus nerve agents
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发布时间： - 摘要：A high performance liquid chromatography（HPLC）coupled with inductively coupled plasma mass spectrometric（ICP-MS） method was developed for the determination of six kinds of inorganic elements，including Cr（Ⅵ），Cr（Ⅲ），As（Ⅲ），As（Ⅴ），Se（Ⅳ）and Se（Ⅵ）in juice drinks.After ultrasonic extraction，the samples were added with EDTA solution，separated with a C8 column using 0.1 mmol/L tetrabutyl ammonium hydroxide，0.1 mmol/L ammonium acetate and 10% methanol as mobile phases，and then determined by ICP-MS.The DRC mode was used to eliminate the interference and ensure the accuracy of determination.The detection limits for the 6 element speciations were 0.34，0.20，0.50，0.40，0.82 and 0.90 μg/L，respectively.The recoveries for the analytes were between 79.5% and 112% with the relative standard deviations（RSDs）（n=6）less than 5.0%.Using this method，six inorganic speciations were undetected in apple juice，while Cr（Ⅲ）and Se（Ⅳ）were detected in blueberry juice with contents of 0.007 mg/kg and 0.015 mg/kg，respectively,and 3 element speciations were detected in cereals juice with contents of 0.008-0.034 mg/kg.关键词：high performance liquid chromatography-inductively coupled plasma mass spectrometry;inorganic morphology of elements;juice drinks;As;Se;Cr
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发布时间： - 摘要：As traditional slab gel electrophoresis has some disadvantages such as tedious operation steps，long experimental time and possible damage to human health from ultraviolet light，a rapid gel electrophoresis system was developed based on electrophoresis biochip，which could realize the separation and imaging of DNA by adding the DNA sample into the biochip.Taking the 20，50 and 100 bp DNA ladder as target compounds，the DNA fragments were separated in the gel electrophoresis system，and the optimal electrophoretic parameters were as follows:the electric field strength:100 V/cm，the agarose mass concentration:1%.Results showed that all the DNA samples could be efficiently resolved in 14 min with the correlation coefficient between migration distance and the DNA size higher than 0.91.Besides，the instrument could run with a good stability.关键词：electrophoresis biochip;DNA;electrophoresis system
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发布时间： - 摘要：The nerve agents are the most toxic among the chemical warfare agents.Many terrorist incidents with nerve agents have occurred in the world.Therefore，it is necessary to develop a portable field detection method for nerve agents.Compared with other methods for detecting nerve agents，the colorimetric method based on reaction color has many advantages，such as reaction visual phenomenon，low cost and rapid onsite detection.Herein，the principles of detection methods and chromogenic agents for detecting nerve agents based on the chromogenic reaction are reviewed，and an outlook for the future development of the colorimetric detection on nerve agents is proposed.关键词：nerve agents;colorimetry;chromogenic reagent;review
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