最新刊期
卷 33 ， 期 12 ， 2014
- 摘要：A dispersive solid phase extraction（d-SPE）/high-resolution benchtop Q Exactive mass spectrometric（HRMS） method was established for the rapid screening of pesticide multi-residue in green pepper.The samples were extracted with acetonitrile，and cleaned up by dispersive solid phase extraction with N-propyl ethlene diamine（PSA） and C18.The chromatographic analysis was performed on a BEH C18 column using acetonitrile（containing 0.1% formic acid） and 4 mmol/L ammonium formate（containing 0.1% formic acid） solution as mobile phases by a gradient elution program.The multi-residue pesticides were analyzed by Q Exactive high-resolution mass spectrometry in switching positive and negative modes,which were applied in rapid screening of pesticides for EU checking pepper samples.16 pesticide analytes were screened qualitatively from the checking pepper sample and were carried on the quantitative analysis.The method showed a good linearity in a certain concentration range for 16 pesticides with average recoveries of 81.6%-116.5% and RSDs of 0.4%-7.5%.The limits of quantitation（LOQs） for 16 pesticides in pepper were between 0.4 μg/kg and 2.0 μg/kg.The method was simple，sensitive and accurate，and was suitable for the rapid screening of multi-residue pesticides in agricultural products.关键词：high-resolution mass spectrometry;pesticides;pepper;dispersive solid phase extraction（d-SPE）;high performance liquid chromatography(HPLC);multi-residue
- 1976
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- 1102
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- 9
发布时间： - 摘要：The copolymerization of o-aminophenol（OAP） and o-phenylenediamine（OPD） was studied by using in situ ultraviolet-visible（UV-Vis） spectroelectrochemical and cyclic voltammetric techniques.The different voltammetric characteristics in homopolymerization and copolymerization processes exhibited the occurrence of the copolymerization between OAP and OPD in 1 mol/L HCl solution.The in situ UV-Vis spectra showed that,during the copolymerization of OAP and OPD,OAP and OPD were firstly oxidized to generate their cation radicals,then the new-formed dimers/oligomers intermediates:phenazine type structure and PANI like backbone structure were formed by the cross-reaction of the cation radicals of OAP and OPD with the OAP and OPD monomers or their cation radicals in solution.The dimers/oligomers intermediates continued to react to form copolymer，showing two absorption peaks located at 477 nm and 419 nm,respectively.Fourier transform infrared Spectroscopy（FT-IR） was used to characterize the formation of the copolymer of OAP and OPD.Further studies showed the difference between the copolymerization of OAP and OPD with different concentration ratios,indicating the dependence of the copolymerization on the concentrations of OAP and OPD.关键词：o-aminophenol;o-phenylenediamine;copolymerization;in situ UV-Vis spectroelectrochemistry
- 2243
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- 988
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- 0
发布时间： - 摘要：A comprehensive analytical method was established for the simultaneous determination of 14 sulfonamides（sulfadimidine,sulfadiazine,sulfadimethoxine,sulfathiazole,sulfapyridine,sulfachloropyridazine,sulfamerazine,sulfacetamide,sulfatroxazole,sulfaphenazole,sulfabenzamide,sulfamethizole,sulfamethoxypyridazine and sulfamethoxazole） in raw milk by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry（UHPLC-Q TOF MS）.The accurate mass and two-stage mass spectrometry databases of 14 compounds were established.The analytes in milk samples were extracted with acetonitrile containing 0.1%formic acid.The extracts were cleaned up through QuEChERS method. The target compounds were separated on an Agilent ZORBAX SB C18 column by gradient elution using acetonitrile-01% formic acid solution as mobile phase,and detected by MS in Dual AJS ESI+ mode.The 14 sulfonamides could be separated in 8 min.As a result,the limits of quantitation（LOQ,S/N=10）of 14 target compounds were 10 μg/kg in milk.The average recoveries of 14 analytes spiked at three concentration levels in the range of 72.5%-117.1% with relative standard deviations of 1.3%-10.9%.The precision mass,retention time,isotopic abundance and two-stage ion mass spectra were employed for the screening and confirmation.This method could be applied in the high-throughput screening and qualitative identification of 14 sulfonamides in raw milk due to its fastness,simplicity and relatively high sensitivity.关键词：ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry（UHPLC-Q TOF MS）;raw milk;sulfonamides;rapid screening
- 2182
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- 1081
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- 8
发布时间： - 摘要：In this paper,the adsorption properties of a new reversed-phase and strong cationic exchange solid phase extraction（SPE） cartridge were studied by using high performance liquid chromatography tandem mass spectrometry（HPLC-MS/MS）.The optimum experimental conditions,including pH value,flow rate,the maximum adsorption capacity and the saturated adsorption capacity were investigated.The adsorption kinetics at different initial concentrations,the thermodynamics at different temperatures and the isotherms of melamine on the new SPE sorbent were studied.The optimal conditions were as follows:pH value:5.0,flow rate:1.0 mL/min,elution volume:1.0 mL,the maximum adsorption capacity:900 μg.The saturated adsorption capacity at pH 5.0 and 30 ℃ was 81.45 μg/mg.The adsorption kinetic data were well described with pseudo-second-order model and the equilibrium data were well fitted by Langmuir model.The calculated thermodynamic parameters indicated that the adsorption of melamine on the new SPE sorbent was spontaneous and endothermic,and the adsorption was a chemisorption process.关键词：new reversed-phase and strong cationic exchange SPE cartridge;adsorption properties;melamine;high performance liquid chromatography tandem mass spectrometry（HPLC-MS/MS）
- 1765
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- 909
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- 0
发布时间： - 摘要：An online cleanup/LC-MS/MS method was established using the restricted access molecularly imprinted polymer cartridge against β-agonist after the optimization of the condition of online cleanup and combination of switching valve.The samples were extracted with ammonium acetate buffer after enzyme hydrolysis,and cleaned up with an online molecularly imprinted cartridge.The detection of clenbuterol and ractopamine was carried out by MS/MS under multiple reaction monitoring mode after separated on a CAPCELL PAK C18 column（2.1 mm×100 mm,5 μm）.An internal standard method was used for quantitative analysis.The limits of quantitation for clenbuterol and ractopamine were 0.02 μg/kg and 0.09 μg/kg,respectively.The spiked recoveries for clenbuterol at spiked concentration levels of 0.05-0.20 μg/kg,and for ractopamine at spiked concentration levels of 0.5-2.0 μg/kg in pork,beef,sausage and milk powder samples were between 84.0% and 103.8% with RSDs less than 12%.关键词：restricted access molecularly imprinted polymer cartridge;online cleanup;clenbuterol;ractopamine;animal origin food
- 2877
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- 1105
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- 4
发布时间： - 摘要：A method for the determination of albendazole（ABZ） by resonance Rayleigh scattering（RRS）,second-order scattering（SOS） and frequency doubling scattering（FDS） at the nanogram level using 12-tungstophosphoric acid（TP） was presented.It was found that ABZ could react with TP and form an ion-association complex by 3∶1 in pH 1.2 HCl medium,which induced the enhancement of RRS,SOS and FDS intensities.In certain ranges,the increments of scattering intensity（ΔI） were directly proportional to the concentrations of ABZ.The detection limits（3σ） for ABZ were 1.98 μg/L（RRS）,3.75 μg/L（SOS） and 5.07 μg/L（FDS）,respectively.The sensitivity of RRS method was higher than that of SOS and FDS methods.The optimum conditions of RRS method and the influencing factors were discussed.In addition,the composition of ion-association complex and the reaction mechanism were investigated.With a good selectivity,the method was successfully applied for the determination of ABZ in tablets and human urine samples with satisfactory results.关键词：resonance Rayleigh scattering;second-order scattering;frequency doubling scattering;albendazole（ABZ）;12-tungstophosphoric acid
- 1807
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- 897
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- 1
发布时间： - 摘要：The electrochemical behaviors and electrochemical quantitative determination of meloxicam(MLX) at acetylene black(AB) and 1-benzyl-3-methylimidazole hexafluorophosphate(［BnMIM］PF6) ionic liquid composite modified carbon paste electrode(AB-［BnMIM］PF6/CPE) were investigated by electrochemical methods.The experimental results indicated that AB-［BnMIM］PF6/CPE showed a good promotion for MLX electrochemical oxidation.The electrode reaction kinetics parameters of MLX on AB-［BnMIM］PF6/CPE were measured.There are good linear relationships between oxidation peak current of MLX and its concentration in the ranges of 6.0×10-7-1.0×10-5 mol?L-1 and 1.0×10-5-1.0×10-4 mol?L-1.The linear equations are Ip(μA)=7.607+1 608 C(mmol?L-1)，r=0.993 4，and Ip(μA)=20.68+267.6 C(mmol?L-1)，r=0.997 9,respectively.The limit of detection(S/N=3) is 2.2×10-8 mol?L-1.The proposed method was successfully applied in the electrochemical quantitative determination of MLX contents in commercial tablet samples with RSDs of 1.2%-3.0% and recoveries of 96.2%-100.1%.关键词：meloxicam;［BnMIM］PF6;AB;modified carbon paste electrode;electrochemical behaviors;electrochemical determination
- 1879
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- 969
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- 2
发布时间： - 摘要：A method was developed for the determination of pyraflufen-ethyl and its metabolite E-1 residues in cotton plant,cotton seeds and soil by using QuEChERS/high performance liquid chromatography coupled with variable wavelength detector（HPLC/VWD）.The residues in the samples were extracted with acetonitrile-water,cleaned up by the developed QuEChERS method,and separated on a Welch Ultimate XB-C18 column（250 mm×4.6 mm,5 μm）,then analyzed by HPLC/VWD at a detection wavelength of 246 nm.The pyraflufen-ethyl and E-1 residues were quantified by the external standard method using the matched standard solution to compensate for matrix effect.Under the optimal conditions,the calibration curves showed good linearities in the range of 0.01-1.0 mg/L for pyraflufen-ethyl and E-1,with correlation coefficients（r2 ） more than 0.999.The average recoveries of pyraflufen ethyl and E-1 at three spiked levels were in the ranges of 83.5%-106.3% and 74.9%-102.3%,respectively,with relative standard deviations（RSDs,n=5） of 0.5%-5.2% and 1.6%-19.2%,respectively.The limits of detection（LOD,S/N>3） of two analytes were both 0.1 ng,the limits of quantitation（LOQ） were 0.04 mg/kg for cotton plant,0.04 mg/kg for cotton seeds and 0.02 mg/kg for soil.The method is rapid,simple,inexpensive,and could be applicable to confirm the residues of pyraflufen-ethyl and its metabolite E-1 in cotton plant,cotton seeds and soil in routine laboratories.关键词：QuEChERS;high performance liquid chromatography（HPLC）;cotton;pyraflufen-ethyl and its metabolite;residue
- 2319
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- 1039
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- 1
发布时间： - 摘要：An effective method was established for the simultaneous determination of the residual contents of 12 glycol ethers in leather and its products.Glycol ethers in leather and leather products were microwave-assisted extracted at 85 ℃,using methanol as extraction solvent.The extracts were purified with solid phase extraction(SPE) column,and analyzed by gas chromatography-mass spectrometry/selected ions monitoring technique(GC-MS/SIM) with the external standard method.The spiked average recoveries varied from 81.1% to 95.9% with relative standard deviations(RSDs) of 1.4%-9.6%.The limits of quantitation(LOQ,S/N=10) for analytes were in the range of 0.05-0.20 mg/kg.The proposed method was simple,rapid,sensitive and accurate,and could satisfy completely the technical demands for the determination of glycol ethers residual in leather and its products and provide a reference for the relevant testing standard.关键词：microwave-assisted extraction;leather;gas chromatography-mass spectrometry(GC-MS);glycol ethers
- 1815
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- 974
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- 5
发布时间： - 摘要：An HPLC-MS/MS method was developed for the determination of acid orange Ⅱ and metanil yellow in food such as bean products,vegetables,pepper products,hotpot condiment,meat and aquatic products.The samples were extracted with 70% acetonitrile.The crude extracts were further purified with an Oasis WAX SPE column,and then filtered through a polytetrafluoroethylene(PTFE) organic membrane.The separation was performed on a Thermo Hypersil Gold aQ(100 mm×2.1 mm,1.9 μm) column by gradient elution using acetonitrile-water as mobile phase.The analytes were analyzed in electrospray ionization(ESI-) under multi reaction monitoring(MRM) mode,and quantified by the matrix matched external standard method.The results showed that the acid orange Ⅱ and metanil yellow in the six samples displayed good peak shapes.The calibration curves were linear in the range of 1.0- 20 μg?L-1,with correlation coefficients more than 0.995.The quantitation limits(LOQ,S/N=10) of acid orange Ⅱ and metanil yellow in low-fat food products(bean-products,vegetables and pepper products) were 1.4,1.0 μg?kg-1,respectively,and in high-fat foods(hotpot condiment,meat and aquatic products) were 2.0,1.4 μg?kg-1,respectively.The recoveries of acid orange Ⅱ and metanil yellow in the six samples were in the range of 65.8%-99.0% with relative standard deviations (RSD) of 2.4% - 6.0%.The method was sensitive and reliable in the determination of acid orange Ⅱ and metanil yellow in food products.关键词：acid orange Ⅱ;metanil yellow;HPLC-MS/MS;food product
- 1815
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- 876
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- 1
发布时间： - 摘要：A method for the determination of 7 bisphenol A-type compounds in canned foods by high performance liquid chromatography with fluorescence detection（HPLC/FLD） was established.Samples were extracted with acetonitrile,and cleaned up with a polyvinylpyrrolidone（PLS） cartridge.Chromatographic separation was carried out on a phenyl column（250 mm×4.6 mm,5 μm） with acetonitrile-water as mobile phase by gradient elution.The baseline separation of seven bisphenol A-type compounds was obtained.Excitation and emission wavelengths of fluorescence detection were set at 227 nm and 313 nm,respectively.For seven bisphenol A-type compounds,there were good linear relationships between concentrations and peak areas in the range of 0.010-5.0 μg/mL,and the correlation coefficients（r2） were greater than 0.99.The average recoveries of 7 bisphenol A-type compounds at fortified levels of 0.015-5.0 mg/kg ranged from 83.7% to 95.5%,with relative standard deviations（RSDs） of 7.2%-19.8%.The limits of detection（LOD） and quantitation（LOQ） were in the range of 5-18 μg/kg and 15-50 μg/kg,respectively.This method was accurate,sensitive and reliable,and could be applied in the real sample analysis.关键词：food;bisphenol A-type compounds;high performance liquid chromatography(HPLC);fluorescence detection
- 2393
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- 1007
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- 4
发布时间： - 摘要：An analytical method was established for the determination of baicalin and dictamnine in cosmetics by ultra performance liquid chromatography（UPLC）.Different types of samples were extracted by ultrasonication with methanol-phosphate buffer solution（9∶1，pH 2.5）.After demulsified by addition of appropriate NaCl,sample extracts were separated on an ACQUITY UPLCTM CSH C18 column（2.1 mm×100 mm,1.7 μm,Waters） by gradient elution using acetonitrile-0.1% fomic acid as mobile phase.The detective wavelength was 314 nm.For the target compouds,the calibration curves were linear in the range of 0.05-10 mg/L,with correlation coefficients more than 0.999.The method limits of detection（LOD,S/N=3） for both were 0.3 mg/kg.The average recoveries ranged from 92.2% to 103.1% with relative standard deviations（RSDs） less than 4%.Meanwhile,the confirmed method was developed by ultra-performance liquid chromatography quadrupole-time-of-flight mass spectrometric（UPLC-Q-TOF） with a parent ion and a product ion monitored.The accuracy of molecular ions was less than 5 ppm.By this method,a degradation product of baicalin was also identified.关键词：cosmetics;baicalin;dictamnine;ultra performance liquid chromatography（UPLC）;UPLC-Q-TOF
- 2264
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- 969
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- 1
发布时间： - 摘要：In this paper,an rGO-AuNPs modified GCE was constructed by the single step electrochemistry reduction method.The microstructure of different modified layers was characterized by transmission electron microscopy（TEM）. Electrochemical impedance spectroscopy and cyclic voltammetry were utilized to instruct the different complex modified GCE,and the data obtained illustrate the excellent performance of the rGO-AuNPs modified GCE.Besides,pH value of electrolyte and the per-enrichment time of PCP were optimized,pH 6.0 PBS buffer and 6 min of pre-enrichment time were used for the following experiments.Based on this,a PCP detection method with high sensitivity,selectivity,stablity and low detection limit was construced.The linear range of PCP ranged from 2.0×10-9 mol/L to 3.0×10-8 mol/L with a limit of detection（LOD） of 1.0×10-9 mol/L.The method was successfully employed to detect PCP in three kinds of wood samples and textile samples.The results showed that the average recoveries ranged from 89.0% to 96.5% with RSDs not more than 4.0%.The above experiments showed that the method is reliable and could be used for the determination of PCP in the wood samples and textile samples.关键词：wood;textiles;pentachlorophenol;electrochemistry;detection
- 1981
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- 1043
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- 2
发布时间： - 摘要：In order to study the structural periodic variation characteristics of silk fibroin dissolved in calcium chloride，spectroscopic techniques（e.g.static fluorescence spectroscopy，UV-vis absorption spectroscopy and Raman spectroscopy） were used to monitor and investigate the conformational transition of silk fibroin in aqueous solutions under different dissolution time for the first time.It was shown that silk fibroin dissolved in calcium chloride（CaCl2∶H2O=111∶180，mass ratio） at about 90 ℃.With the extension of dissolution time from 0 min to 30 min，calcium ions progressively penetrated into the silk fibroin molecules，and forming chelate complex with hydroxyl ligand of serine（Ser） and tyrosine（Tyr） side chain.In addition，silk fibroin began to swell，molecular structure also became gradually loose.At the same time，tryptophan（Trp） and Tyr buried in the area of noncrystalline also were gradually exposed，molecular conformation was also mainly shifted from β-sheet crystal to α-helix or random coil.It was also found that the aggregating of hydrophobic side chains was increased with increase of dissolution time via exogenous fluorescence probe of 8-anilino-1-naphthalenesulfonic acid（ANS）.Experimental results obtained from the scanning electron microscope（SEM） confirmed that almost all of silk fibers were dissolved within 30 min，presenting globular structure.While previously，a certain amount of residual fibroin fibers existed with relatively loose zonal structure，then becoming layered structure.Therefore，the results obtained have a important practical significance for the time controlling of silk fibroin dissolution in calcium chloride solution.关键词：silk fibroin;conformation transition;fluorescence spectrum;ultraviolet-visible absorption;Raman spectroscopy
- 2102
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- 1003
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- 4
发布时间： - 摘要：A method was developed for the quantitative determination of amitraz and its metabolites in pond-water by solid phase extraction and liquid chromatography-tandem mass spectrometry .The extraction and separation efficiencies of analytes were investigated using different organic solvents and SPE columns.In the optimal conditions,the calibration curves were linear in the range of 20-2 000 ng/L.The limits of detection for amitraz and its metabolites were in the range of 0.4-1.0 ng/L.The recoveries of these analytes were in the range of 69.7%- 91.3%.This method exhibited high sensitivity,good repeatability,long-time stability and specificity,and could be used to detect amitraz and its metabolites in pond-water．关键词：amitraz;N-2,4-dimethylphenyl-N-methyl-formamidine;2,4-dimethylformamidine;2,4-dimethylaniline;SPE extract;pond-water;LC-MS/MS
- 1910
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- 1044
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- 4
发布时间： - 摘要：In this paper,an amplified electrochemical immunoassay using nanocomposite based labels（{dAb-ZnO-FCA}） was developed for the assay of E-coli as indicator bacteria relevant to the quality of dairy product.The {dAb-ZnO-FCA} labels were designed by exploiting nanocomposite（ZnO@SiO2） as the carriers for immobilization of detection antibody（dAb） and ferrocenecarboxylic acid（FCA）,in which dAb was used for recognition of E-coli and FCA tags served as signal-generating molecule.Greatly amplified signal was achieved in the sandwich-type immunoassay when enormous FCA linked to ZnO@SiO2.Under the optimal experimental conditions,a linear relationship between peak current of FCA and logarithmic value of E-coli concentration was obtained in the range of 2.0×102-2.0×106 cfu/mL with a detection limit（S/N=3） of 100 cfu/mL.The proposed method was used to determine E-coli in dairy product,and the recoveries of standard additions were in the range of 95.8%-105%.The results indicated that the electrochemical immunoassay gave a useful approach for E-coli analysis with rapid response,high sensitivity and specificity,and thus provided a powerful tool for estimating the quality of dairy product.关键词：nanocomposite-based labels;amplified electrochemical immunoassay;dairy product;E-coli
- 2162
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- 1012
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- 1
发布时间： - 摘要：As the high resolution and wide mass measurement range characteristics of a time-of-flight mass spectrometer,a high precision and wide range data acquisition system was designed in this paper.The system completed the amplification,discrimination and level conversion for the front end signal.A high precision time interval measuring chip TDC-GPX was used to measure the pulses’ time interval.A field programmable gate array（FPGA） realized the sequential control.A Universal Serial Bus（USB 2.0） interfaced with a computer.The host computer’s controlment and high-speed data transmission were realized with the time division multiplexing technology.Testing results showed that the single-shot precision is less than 100 ps,the range of measurement time is beyond of 500 μs and the number of measurement channels could be up to 8.关键词：time-of-flight mass spectrometer;time to digital converter（TDC）;data acquisition;FPGA
- 2090
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- 1037
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- 2
发布时间： - 摘要：In this paper，the toxic mechanisms of 2-mercaptobenzimidazole to lysozyme were investigated using spectroscopic and molecular modeling methods under physiological conditions，the binding characterization of 2-mercaptobenzimidazole(MBI) and lysozyme was analyzed，and the changes of conformation and enzyme activity of lysozyme were explored and simulated.The results showed that 2-mercaptobenzimidazole could effectively quench the intrinsic fluorescence of lysozyme via static quenching.The number of binding sites，binding constant and thermodynamic parameters were measured at different temperatures.2-Mercaptobenzimidazole could spontaneously bind with lysozyme through hydrogen bond and van der Waals forces.The results of docking studies showed that 2-mercaptobenzimidazole could bind into the activity site of lysozyme，which further induced the influence on the conformation and enzyme activity of lysozyme.The study provides important references for exploring the toxic mechanism of 2-mercaptobenzimidazole to lysozyme at the molecular level.关键词：2-mercaptobenzimidazole(MBI);lysozyme;multi-spectroscopic techniques;docking studies;toxicity evaluation
- 1870
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- 964
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- 0
发布时间： - 摘要：An automated solid phase extraction/liquid chromatography-tandem mass spectrometric（ASPE/LC-MS/MS） method for the quantitative determination of clonazepam and its major metabolite 7-aminoclonazepam in blood.The samples were cleaned up with a C18 solid phase extraction cartridge using methanol as elute solution,and separated on a Waters AtlantisTM dC18 column（150 mm×3.9 mm,5.0 μm） by gradient elution using methanol and water（containing 0.1% formic acid） as mobile phase.The analysis of target compounds were carried out by LC-MS/MS under multiple reaction monitoring（MRM） in positive ionization mode.The calibration curves showed good linearities in the concentration range of 2-1 000 μg/L with correlation coefficients more than 0.995 9.The detection limits of the method were in the range of 0.2-0.5 μg/L.The mean recoveries at three spiked levels of 50,200,1 000 μg/L were in the range of 72.6%-96.3%,with relative standard deviations of 4.2%-10.3%.The proposed method was rapid,sensitive,simple and accurate,and could be used to detect clonazepam and 7-aminoclonazepam in forensic toxicology．关键词：clonazepam;7-aminoclonazepam;liquid chromatography-tandem mass spectrometry;automated solid phase extraction;blood
- 1944
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- 882
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- 5
发布时间： - 摘要：Screen printed carbon electrode(SPCE) herein was fabricated by screen printing technique,and then activatedly pretreated by soaking it into concentrated NaOH solution.The treatment effect was evaluated by electrochemical impedance method and cyclic voltammetry.The result showed that the electron transfer resistance(Rct) decreased with the soaking time.The peak to peak separation(Ep) in cyclic voltammetry was reduced from 400 mV to 84 mV,and the peak current was gradually increased.The ratio between oxidation peak current and reduction peak current was close to 1∶1,indicating that the electrochemical reversibility was greatly promoted.In addition,compared with that of the fresh SPCE unactivated,electrogenerated chemiluminescence(ECL) of ［Ru(bpy)3］2+ was enhanced by a factor of 36 after pretreatment in concentrated NaOH solution.The experimental results also showed that the ECL of ［Ru(bpy)3］2+ was promoted after adding dopamine into borate buffer without coreactants.Based on this principle,a novel ECL sensor for determination of dopamine was constructed.Effect of pH value was studied.Under the optimized conditions,the ECL intensity showed a good linear relationship toward dopamine over the concentration range of 1.0×10-10-5.0×10-7 mol/L with a limit of detection of 5.0×10-11 mol/L.This proposed method was applied in the analysis of dopamine in practical injection samples,with recoveries of 95% - 102%.The method was simple and cost effective,and could realize batch production in design and in operation with high sensitivity and stability.关键词：electrogenerated chemiluminescence (ECL);screen printed carbon electrode;dopamine;borate buffer
- 1899
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- 1045
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- 2
发布时间： - 摘要：Tetrodotoxin（TTX）is a highly toxic low-molecular and non-protein neurotoxin,and its property is relatively stable.There is no specific antidote for it.The three main detection technologies for tetrodotoxin are bioassays,physicochemical detection methods and immunoassays,among which the immunoassay is more widely used because of its celerity,conciseness and delicacy.In this paper,advances in technology of sample pretreatment for tetrodotoxin,rapid immunoassay technology for tetrodotoxin and its related patents were reviewed.The new techniques for tetrodotoxin detection was prospected.关键词：tetrodotoxin(TTX);rapid detection;sample pretreatment;immunological detection;monoclonal antibody
- 1926
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- 1014
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- 4
发布时间：
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