最新刊期
卷 35 ， 期 9 ， 2016
- 摘要：The primary objective of this study is to evaluate the binding characteristics of human serum albumin（HSA） and 5′-hydroxy-2,2′,4,4′,5-pentabromo diphenyl ether（5′-OH-BDE-99） in physiological conditions.Several spectroscopy techniques such as steady-state fluorescence spectroscopy,time-resolved fluorescence,FTIR and three-dimensional fluorescence spectrometry, combined with molecular docking and molecular dynamics simulation were employed to comprehensively analyze the mechanism of interaction between 5′-OH-BDE-99 and HSA.The results of fluorescence spectroscopy experiments,non-radiation energy transfer theory and dynamic simulation showed that 5′-OH-BDE-99 could quench the intrinsic fluorescence of HSA through static quenching mechanism.The experiments of FTIR,three-dimensional fluorescence spectra and dynamic simulation revealed that the binding of 5′-OH-BDE-99 to HSA could induce conformational and microenvironmental changes.Moreover,according to molecular docking and thermodynamic method,hydrophobic force is the main acting force.关键词：polybrominated diphenyl ethers;human serum albumin（HSA）;fluorescence spectroscopy;molecular docking;dynamic simulation
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发布时间： - 摘要：G-Fe3O4 magnetic composite materials with excellent adsorption properties were successfully synthesized by solvothermal method,and then applied in magnetic solid phase extraction(MSPE) process for 9 common pesticides in peanut samples.The extraction conditions were optimized,such as dilution ratio of sample extract,amount of magnetic composite materials,extraction time,type and dosage of elution solvent.Coupled with gas chromatography-tandem mass spectrometry(GC-MS/MS),a novel multi-residue analytical method was established for these nine pesticides in complex peanut matrix.The results showed that the limits of detection for nine pesticides ranged from 0.07μg/kg to 1.85μg/kg,the linear ranges were 0.23-1000μg/kg,and the correlation coefficients(r2) were not less than 0.994.The average recoveries at three spiked levels ranged from 81.9% to 119.3%,with relative standard deviations(RSD) of 2.1%-6.6%.With the advantages of simple operation,high recovery,good stability and low cost,this method was a rapid,efficient and accurate technique for multi-residue determination of pesticide,especially in high fatty matrix such as peanut sample.关键词：magnetic solid phase extraction(MSPE);gas chromatography tandem mass spectrometry(GC-MS/MS);pesticide residues;peanut
- 1874
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- 999
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- 6
发布时间： - 摘要：According to the system resonance light scattering intensity will change with the variation of AgNPs aggregation state before and after the reaction,a novel resonance light scattering（RLS） method for the quantitative determination of trace hydrogen peroxide was developed using silver nanoparticles（AgNPs） as the resonance scattering probe.The silver nanoparticle with an average particle size of 4 nm was synthesized through the reduction of silver nitrate by sodium borohydride,using trisodiumcitrate as the protecting agent.The detection of H2O2 mechanism was based on that Mn2+ was chelated by the citrate covering on the surface of the silver nanoparticles, inducing the aggregation of AgNPs with increasing of resonance scattering intensity of the system.When H2O2 was added to the system,Mn2+ participated in Fenton-like reaction with H2O2 producing Mn3+ and hydroxyl radical（?OH）.The complexation reaction of citrate on the surface of the AgNPs with Mn3+ formed unstable complexes,and ?OH oxidatively etched AgNPs.Both of the two reactions could result in non-aggregation of AgNPs as well as relatively weakening resonance scattering intensity of the system. Under the optimal conditions,the resonance light scattering intensity of system at 411 nm was decreased linearly with concentration of H2O2 over the range of 7.88×10-8-1.418×10-5 mol/L,with a correlation coefficient of 0.9967 and a detection limit of 4.04×10-8 mol/L. This method was applied in the analysis of hydrogen peroxide in the lake and rain water samples with satisfactory results.关键词：hydrogen peroxide;silver nanoparticles;resonance light scattering;Fenton-like reaction
- 1613
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- 923
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发布时间： - 摘要：A novel electrochemical immunosensor for microcystin-（leucine-arginine）（MCLR） was developed based on gold electrode modified with Au nanoparticles（AuNPs）.The AuNPs were prepared by the sodium citrate reduction method,and characterized by transmission electron microscopy（TEM） and UV-vis absorption spectroscopy.1，6-hexanedithiol（HDT） molecules were modified onto the surface of a gold electrode to form self-assembly monolayer, and then the AuNPs were assembled on the self-assembly monolayer of HDT. The immunosensor was constructed by immobilizing the antibody of microcystin-（leucine-arginine）（anti-MCLR） on the modified electrode. The surface morphology of the AuNPs modified electrode and the electrochemical behaviour of the immunosensor were characterized by scanning probe microscopy，cyclic voltammetry and electrochemical impedance spectroscopy（EIS），respectively.MCLR and horseradish peroxidase conjugated MCLR（MCLR-HRP） competitively combined with immobilizing anti-MCLR. The determination of MCLR using the immunosensor was investigated by differential pulse voltammetry（DPV）.Under the optimized conditions，a linear range from 0.01μg/L to 25μg/L and a detection limit of 0.005μg/L were obtained by DPV method.The reproducibility，stability and selectivity of the immunosensor for MCLR were investigated. The proposed method was applied in the determination of MCLR in real water samples with recoveries of 100%-102%,and the determination results of MCLR were consistent with those obtained by HPLC method.关键词：microcystin;gold nanoparticles;self-assembly;immunosensor
- 1886
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- 1321
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- 1
发布时间： - 摘要：Complexing extraction was applied in the pretreatment of eight synthetic pigments such as tartrazine,new red,amaranth,ponceau 4R,sunset yellow,allura red,brilliant blue and erythrosine in candy with tri-n-octylamine(TNOA) as complexing agent and tetrachloromethane as diluent. Effects of operation conditions such as pH of working solution,kind of diluent,TNOA concentration and the strip solution composition on pretreatment efficiency were investigated.Results showed that when pH value of working solution was 6.0,the diluent was tetrachloromethane,TNOA concentration was 5% and the strip solution was ethanol-15% ammonium solution(1∶1,by volume),the recoveries of eight synthetic pigments were in the range of 90%-98%.The results indicated that the method showed the advantages of simplicity,rapidness,low solvent consumption and high recovery, and was suitable for the separation and extraction of synthetic pigments in candy.关键词：tri-n-octylamine(TNOA);synthetic pigment;complexing extraction;HPLC
- 1755
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- 920
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- 1
发布时间： - 摘要：A high performance liquid chromatography-quadrupole ion mass spectrometric（HPLC-QTRAP-MS/MS） method was developed for the determination of two potential genotoxic impurities（impurity C and impurity D） residues in dronedarone hydrochloride.After extracted with 0.1% formic acid-acetonitrile（20∶80），the dronedarone hydrochloride samples were separated on an Agilent Extend-C18 column（1.8 μm,2.1 mm×50 mm） or a YMC Pack-CN column（5 μm,46 mm× 250 mm） with two mobile phases of 0.1% formic acid and acetonitrile.The detection of analytes was performed in the positive mode and selective reaction monitoring（SRM） mode.As a result，the calibration curves of impurity C and impurity D showed good linearity in the range of 1.0-50 μg/L.The limits of detection（S/N=3） were 0.20 μg/L and 0.30 μg/L,respectively.The limits of quantitation（S/N=10）were 0.80 μg/L and 1.0 μg/L，respectively.The method has the advantages of simple operation，high sensitivity，good reproducibility，and could be used for the detection of two genotoxic impurities residues in dronedarone hydrochloride.关键词：high performance liquid chromatography-quadrupole ion mass spectrometry（HPLC-QTRAP-MS/MS）;potential genotoxic impuritie;dronedarone hydrochloride;residues
- 1896
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- 945
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- 6
发布时间： - 摘要：A new method was established to determine 10 kinds of fungicides（including sulfanilamide，benzimidazole，BIT，MBT，IPBC，PCMC，salicylanilide，OPP，TCMTB，OIT） in leather samples by ultrasonic extraction combined with ultrahigh performance liquid chromatography（UPLC）.The leather samples were ultrasonically extracted with methanol，and separated with T3 column，employing methanol and 0.1%（by volume） formic water as mobile phase by gradient elution．All of the samples were detected with diode-array detector.The 10 kinds of analytes presented favorable linearity in a certaim concentration range，with correlation coefficients（r2） not less than 0.999 3.The method quantitation limit（LOQ，S/N=10） of IPBC was 190.0 mg/kg，and the LOQs of other compounds were in the range of 4.0-8.0 mg/kg.The average recoveries（n=6） ranged from 81.3% to 104.9%，and the relative standard deviations （RSD，n=6） were in the range of 4.7%-11.2%.With the advantages of simple pre-treatment procedure and satisfactory separate effect，the developed method was suitable for the simultaneous determination of 10 kinds of fungicides in leather samples.关键词：leather;fungicide;ultrasonic extraction;ultrahigh performance liquid chromatography（UPLC）
- 1684
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- 3
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- 2
发布时间： - 摘要：In this study,concentrated sulphuric acid was employed for the determination of hydrocortisone biotransformation rate,which could be monitored via dual wavelength analysis.A rapid and simple method for the determination of hydrocortisone biotransformation rate was developed by combining the well-known Lambert Beer law and the 3D data modeling method.The method recoveries were in the range of 96.9%-110.8%.The validation results,which were consistent with that of HPLC method,showed that the method could meet the needs for preliminary screening of Absidia coerulea via high-throughput system.This study has a good application prospect in breeding Absidia coerulea of high specific biotransformation ability.关键词：hydrocortisone;biotransformation rate;dual wavelength analysis;high throughput selection
- 1740
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- 868
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发布时间： - 摘要：A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)combined with QuEChERS method was developed for the simultaneous qualitative and quantitative analyses of four metabolites of nitrofuran antibiotics,including semicarbazide(SEM),1-amino-hydantoin(AHD),3-amino-2-oxazolidinone(AOZ),5-morpholino-3-amino-2-oxazolidone(AMOZ).The samples were hydrolyzed with HCl,and derivatized with 2-nitrobenzaldehyde at 37 ℃ for 16 h.The derivative solutions were adjusted to pH 7.0-7.5.The analytes were extracted and pured by Bond Elut QuEChERS.The separation was carried out on a C18 column,using acetonitrile-0.1% formic acid as mobile phase by gradient elution.The analytes were detected by tandem mass spectrometry with electrospray ionization source under multiple reaction monitoring(MRM) mode.The method showed a good linearity between peak area ratios of the analytes to the internal standard and concentration of the analytes with correlation coefficients all above 0.999 over the dynamic range of 1.0-10 μg/L.The limits of detection(LODs) and quantitation (LOQs) of four antibiotics were 0.15 μg/kg and 0.5 μg/kg,respectively.The average recoveries of all the compounds at four spiked levels of 0.5,1.0,2.0,5.0 μg/kg ranged from 88.0% to 109.6% with RSDs (n=6) of 3.8%-11.0%.This method was used to detect 200 batches of holothurian in Dalian with the passing percentage of 95%.Compared to the traditional pretreatment method,this method is more easy to operate and less solvent comsuming,and is proved to be fast and effective for the simultaneous qualitative and quantitative analyses of the metabolites of nitrofuran antibiotics in holothurian.关键词：nitrofuran metabolites;QuEChERS;holothurian;high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS)
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- 990
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发布时间： - 摘要：A method for the determination of arginine，lysine，serine，valine and other eleven amino acids was developed by MSTFA derivatization combined with gas chromatography-mass spectrometry（GC-MS），and fifteen amino acids reached the baseline separation.The arginine fermentation broth was purified by cationic exchange mixed-solid phase extraction（SPE）， and then detected successfully by the developed method.Finally the 15N isotope abundance was calculated by characteristic fragment.关键词：gas chromatography-mass spectrometry（GC-MS）;derivatization;amino acids;15N labeled amino acids;isotope abundance
- 1672
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- 3
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- 2
发布时间： - 摘要：The Fe3O4@NiSiO3 magnetic nanoparticles（NPs） were prepared by hydrothermal synthesis and sol-gel method.The nanoparticles microspheres have uniform morphology，good magnetic properties and dispersion.In this study，the synthesized NPs as a magnetic solid phase extraction（MSPE） media were combined with high performence liquid chromatography（HPLC） to develop an effective method for the detection of trace microcystin-LR（MC-LR） in water samples.After optimizing the MSPE and HPLC chromatographic conditions，the method showed a good linear relationship in the range of 0.25-146.5 μg/L with correlation coefficient（r） of 0.999 1.The detection limit was 0.011 μg/L.The method was applied in the analysis of microcystin toxins in pure water sample and actual water samples with recoveries of 81.0% and 66.7%-72.0%，respectively.The results showed that Fe3O4 @NiSiO3 magnetic nanoparticles have good enrichment capability，and could be effectively used for the extraction of trace microcystin in water.关键词：magnetic solid-phase extraction（MSPE）;high performance liquid chromatography（HPLC）;microcystins（MCs）;magnetic nanoparticles
- 1877
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- 932
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- 2
发布时间： - 摘要：A method based on ultra high performance liquid chromatography-high resolution mass spectrometry was developed to separate benzoic acid，sorbic acid，acesulfame-K and saccharin sodium in honey.The targeted compounds in honey samples were extracted with methanol-water mixtures（10∶90）,and separated on a Diamonsil Plus C18 column with 0.5 mmol/L ammonium acetate-methanol as mobile phase by gradient elution.The qualitative and quantitative analyses were operated under t-MS2 by high resolution mass spectrometry with the external standard method.The results indicated that four analytes had good linearities in the concentration range of 0.02-2.0 mg/L with correlation coefficients of 0.998 7-0.999 7.The quantilition limits for benzoic acid，sorbic acid,acesulfame-K and saccharin sodium were 0.5，0.5，0.3,0.3 mg/kg，respectively.The recoveries of four compounds at three spiked levels were in the range of 89.0%-104.0%，with relative standard deviations（RSDs） of 2.0%-7.9%.The method was simple and rapid，and was suitable for the determination of benzoic acid，sorbic acid and acesulfame-K，saccharin sodium in honey.
- 1826
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- 890
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发布时间： - 摘要：A fluorescence resonance energy transfer（FRET）system between fluorescence carbon dots（CDs,donor）and fluorescein（FAM,acceptor）was constructed,and a novel method for the sensitive and selective determination of aspirin（ASP）was accordingly proposed.It was found that in pH 7.0 Tris-HCl buffer，effective energy transfer from CDs to FAM occurred,which resulted in a great enhancement of the fluorescence intensity of FAM.Upon the addition of ASP,fluorescence quenching of FAM occurred,and the change of FAM fluorescence intensity was in a good linearity（r=0.999 6）with ASP in the concentration range of 1.0-150.0 μg/mL.A novel fluorescence quenching platform for the determination of ASP was constructed.Under the optimum conditions,the detection limit of ASP for this method was 0.33 μg/mL（3δ/k,n=11）,and the spiked recoveries ranged from 97.1%to 105.3%with RSD（n=6）not more than 4.6%.The result showed that common relevant substance,cations and anions did not interfere with the detection of ASP.关键词：carbon dots;fluorescein;fluorescence resonance energy transfer（FRET）;aspirin
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- 940
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发布时间： - 摘要：An ion chromatographic(IC) method was developed for the determination of trace anions in high purity sodium hydroxide after sample neutralization and column concentration.Samples were dissolved and diluted with de-ionized water,and then injected into the IC system directly without any further pretreatment．The sample solution was delivered with de-ionized water,firstly on-line filtrated with In Guard H column for pre removing OH-,and then concentrated with IonPac TAC ULP column.The anions under test in the enrichment column were delivered in the IC system when the valve was switched．With the eluent KOH produced by eluent generator at a flow rate of 1.0 mL/min,the anions were separated on an IonPac AS11-HC column and detected with conductivity detector,then quantitively analyzed by the external standard method．The results indicated that the correlation coefficients of chloride,sulfate,chlorate were 0.999 8,0.999 6 and 0.999 2,respectively,in the linear range of 0.1-10.0 mg/L.The detection limits for chloride,sulfate,chlorate were 0.03,0.07,0.06 mg/kg,respectively,and their spiked recoveries were 92%-104%,91%-111% and 92%-106%,respectively,with their relative standard deviations (n=7) not less than 2.0%.The method was applied in the determination of anions in high purity sodium hydroxide samples with satisfactory results.关键词：high purity sodium hydroxide;chloride;sulfate;chlorate;on-line sample neutralization and column concentration;ion chromatography(IC)
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- 894
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发布时间： - 摘要：A method was established to determine the content of empagliflozin by 1H nuclear magnetic resonance spectroscopy（1H-NMR），using gemcitabine hydrochloride and zidovudine as the internal standard，repectively.NMR spectra were recorded using a standard 1D pulse sequence at a 30° flip angle and with DMSO-d6-D2O as the solvent.Thirty two scans of 32 K data points were acquired at a temperature of 303 K，a relaxation delay of 20 s and a line broad of 03 Hz.Under the optimal conditions，method validation indicated specificity，robustness and stability up to 24 h.A good linear relationship was obtained between peak area ratio and molar ratio of empagliflozin to the internal standard.For gemcitabine，the regression equation was y=0.009x-0.003（r2=0.999 9） with a molar ratio range of 0.512 5-1.953 8.For zidovudine，the regression equation was y=0.576x-0.026（r2=0.999 9） with a molar ratio range of 0.494 7-1.966 0.The contents of empagliflozin were 99.83%（n=3，RSD=0.06%）and 99.77%（n=3，RSD=0.19%）corresponding to the internal standards gemcitabine hydrochloride and zidovudine，respectively.The results were consistent with each other，indicating that the method had the advantages of accuracy，high sensitivity and good repeatability，and could be used for the quantification of new drugs.关键词：empagliflozin;quantitative NMR;gemcitabine hydrochloride;zidovudine
- 1660
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- 894
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- 3
发布时间： - 摘要：A novel ion chromatographic method was developed for the determination of organic acids in wipe grapes,including lactic acid,propionic acid，DL-malic acid，D-tartaric acid，oxalic acid，citrate，succinic acid and ascorbic acid.The samples were prepared through extraction decoloration and filtration before analysis,and eluted with 1.5-30 mmol/L KOH produced by an eluent antogenerator.The interference between the coexistence ions which were not examined and adjacent ions was investigated.The results showed that the unexamed inorganic ions made no interference on determination.The eight organic acids showed good linear relationship between mass concentration and peak area in the certain concentration ranges.The detection limits were in the range of 0.064-0.25 mg/L and the average recoveries were 89.5%-96.2%.The method was applied in the determination of eight organic acids in wine grapes from eastern Helan mountain，Ningxia.The results showed that eight organic acids were all detected in wine grapes with high contents of DL-malic acid and D-tartaric acid，citric acid，and low contents of other acids.The wine grapes is a typical tartaric acid fruit.关键词：ion exchange-conductivity detection;organic acids;wipe grapes
- 1978
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- 858
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- 1
发布时间： - 摘要：A novel method for the determination of enantiomers of three N-heterocyclic drugs was developed by revered phase high performance liquid chromatography using cellulose-tris-（4-methylbenzoate） as chiral stationary phase（CSP）. Enantioseparation of oxazepam,pioglitazone and rosiglitazone on the CSP were performed by using mixture of methanol and water as mobile phase. Effects of methanol-water ratio,pH value and temperature on chiral separation of three drugs were investigated,respectively.The results showed that their enantiomers were separated on the CSP with methanol-0.01% acetic acid solution（50∶50） at 25 ℃ under pH 6.0 for oxazepam, methanol-0.01% ammonia solution（60∶40） at 30 ℃ under pH 8.0 for pioglitazone,and methanol-0.01% ammonia solution（65∶35） at 40 ℃ under pH 8.0 for rosiglitazone,respectively. The mechanism of racemic resolution for three drugs was discussed.The proposed method was successfully applied in the determination of three drugs enantiomers in commercial tablets,with recoveries and relative standard deviations（RSDs） of 94.6% -106.2% and 0.07%-1.0%,respectively.It was proved to be simple,reliable and accurate.关键词：reversed phase high performance liquid chromatography（HPLC）;N-heterocyclic chiral drugs;cellulose-tris（4-methylbenzoate）;chiral stationary phase（CSP）;enantioseparation
- 1653
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- 822
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- 1
发布时间： - 摘要：A novel dispersive liquid-liquid microextraction method was developed for the determination of six kinds of benzotriazole UV stabilizers:UV-P,UV-PS,UV-326,UV-327,UV-328 and UV-329 in water samples by gas chromatography with tandem mass spectrometry（GC-MS/MS）.The optimal liquid-liquid microextraction experiment conditions were as follows:50 μL chloroform as extractant solvent，600 μL ethanol as dispersive solvent，pH value of sample:3.0．The target compounds were separated on a Rtx-5MS column（30 m×0.25 mm×0.25 μm） and subsequently determined by triple quadruple mass spectrometry in multiple reaction monitoring mode.Quantitative determination was achieved by the external standard method.The average recoveries of target compounds were in the range of 83.5%-104.5%,with relative standard deviations（RSD,n=5） of 5.1%-10.1%.The method detection limits（LOD） for the six target compounds were in the range of 0.002-0.03 μg/L and the quantitation limits（LOQ） were 0.008-0.1 μg/L.关键词：benzotriazole UV stabilizers;dispersive liquid-liquid microextraction(DLLME);gas chromatography-tandem mass spectrometry（GC-MS/MS）;water
- 1870
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- 1046
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- 1
发布时间： - 摘要：An electrochemical sensor for omethoate detection based on electropolymerized molecularly imprinted polymers（MIPs） was fabricated.The sensitive layer was prepared by electropolymerizing o-phenylenediamine（OPD） on a glassy carbon electrode modified with multi-walled carbon nanotube in the presence of template（omethoate） which could be removed by ethanol.The electrochemical properties of the molecularly imprinted sensor were characterized by cyclic voltammetry and electrochemical impedance spectroscopy（EIS）.The analytical characteristics of the sensor was investigated by differential pulse voltammetry, and an indirect analytical method based on the medium of K3Fe（CN）6 was established.The result showed that a linear relationship between concentration of omethoate and relative peak current change of K3Fe（CN）6 was obtained in the range of 1.0×10-7-2.0×10-6 mol/L, and the detection limit was 3.6×10-8 mol/L.关键词：molecular imprinting;omethoate;multi-walled carbon nanotube;sensor
- 2335
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- 1234
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发布时间： - 摘要：trans-4-Hydroxy-L-proline is one of the valuable chiral building block in the production of many pharmaceuticals.A quantification method of trans-4-hydroxy-L-proline and L-proline from microbial transformation by using reverse phase high performance liquid chromatography （RP-HPLC) was developed.9-Fluorenylmethyl chloroformate（FMOC-Cl) was used as pre-column derivation agent,and the derivatization was proceeded in sodium tetraborate buffer solution（pH 9.9) containing acetonitrile-water（66∶34).The solution then was separated on an Agilent Extend C-18 column by using 0.1% trifluoroacetic acid and acetonitrile as mobile phase,and detected with UV detector at 263 nm.The linear ranges of two amino acid were in the range of 0.01-5.00 mg/mL,with correlation coefficients greater than 0.999.The limits of detection（LOD) were in the range of 5.00-7.00 ng/L,and the average recoveries of trans-4-hydroxy-L-proline and L-proline were 98.9%-102% and 97.9%-100%,respectively.This method provides an effective way to quantify L-proline and trans-4-hydroxy-L-proline in microorganism fermented liquid system with good reproducibility,and high precision.关键词：pre-column derivation;RP-HPLC;trans-4-hydroxy-L-proline;L-proline;microbial conversion
- 1825
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- 834
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- 1
发布时间： - 摘要：A method was developed for the analysis of polycyclic aromatic hydrocarbons（PAHs） in plant leaves by gas chromatography-mass spectrometry（GC-MS） based on silica gel column and gel permeation chromatography（GPC） purification.The target analytes in leaf samples were extracted with dichloromethane-hexane（1∶1，by volume） solution，purified with silica gel column and GPC column，analyzed by GC-MS，and then quantified by the internal standard method.The average recoveries of 15 PAHs were in the range of 82.2%-130% with relative standard deviations（RSD） not more than 11%.The detection limit（LOD） of this method varied from 0.025 1 ng?g-1 to 5.80 ng?g-1.This method could effectively remove the pigment and oil in the plant leaves，suitable for the trace analysis of PAHs in leaf samples，and providing a technical support for the determination of content of PAHs in the plant tissues.关键词：soxhlet extraction;silica gel column;gel permeation chromatography（GPC）;polycyclic aromatic hydrocarbons（PAHs）;gas chromatography-mass spectrometry（GC-MS）;plant
- 1790
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- 822
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- 0
发布时间： - 摘要：To eliminate the interference on the determination of selenium（Se） in royal jelly by inductively coupled plasma mass spectrometry（ICP-MS），a dynamic reaction cell（DRC） method was established by the study of reaction gas species，flow rate and isotope of Se.The results showed that 78Se was suitable for the analysis.The interference on the determination of Se was eliminated when CH4 was used as reaction gas and its flow rate was set to 0.5 mL?min-1.The method had a wide linear range of 0.1-100 μg?L-1 and a low detection limit of 0.052 2 μg?L-1.The relative standard deviations（RSD） were less than 5%.The recoveries were between 95.0% and 103.9%.The differences of the results of Se in royal jelly samples determined by DRC-ICP-MS and atomic fluorescence spectrometry were not significant.关键词：dynamic reaction cell（DRC）;inductively coupled plasma mass spectrometry（ICP-MS）;royal jelly;selenium
- 1709
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- 899
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- 4
发布时间： - 摘要：A method was developed for the determination of methamidophos in soil by accelerated solvent extraction/ultra performance liquid chromatography -mass spectrometry（ASE/UPLC-MS）.The experimental conditions were investigated on the basis of the optimization of ASE conditions,and the optimal conditions were obtained as follows：extraction solvent：acetonitrile,extraction temperature：80 ℃,static extraction time：10 min,cycling twice.The extraction elute was evaporated to dryness with rotary evaporator,and analyzed by UPLC-MS.The target compound was qualitatively analyzed by the external standard method,and qualitatively analyzed by MS/MS method.The linear range was 3.15-1 050 μg/kg for methamidophos,with correlation coefficient（r） of 0.999 1.The recoveries of methamidophos at three spiked levels were in the range of 72%-82% with relative standard deviations of 5.8%-8.6%.The detection limit was 0.05 μg/kg.The method showed the advantages of accuracy,good separation effect and sensitivity,and was suitable for routine sample detection.关键词：accelerated solvent extraction（ASE）;ultra performance liquid chromatography-mass spectrometry（UPLC-MS）;methamidophos;soil
- 1634
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- 913
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- 1
发布时间： - 摘要：A new aided diagnosis of oral cancer was developed for the separation and analysis of nitrosonaphthol reactant（NNR) of urine in oral cavity cancer patients by using high performance liquid chromatography with fluorescence detection（HPLC／FLD),based on the analysis of urine NNR of 34 cases of oral cancer patients and 18 healthy people and their difference of composition content.The experimental results showed that a marker with excitation wavelength of 440 nm and emission wavelength of 539 nm,could be detected in urinary nitrosonaphthol reactant（NNR) from healthy people and patients with oral cavity cancer under the condition of this paper.The marker content was relatively low in oral cancer patients and significantly high in healthy persons,which is quite different from the usual test results.Significant differences were found in the matter content in healthy people and those with oral cancer patients（P<0.01) using a non parametric test （Mann-Whitney U test).Further data analysis showed that the specificity was 94.1%,the sensitivity was 94.4%,the area under the ROC curve（AUC) was 0.989.The model showed a high diagnostic value,and could be used for the auxilary identification of oral cancer.关键词：oral cancer;nitrosonaphthol reactants;high performance liquid chromatography with fluorescence detection（HPLC/FLD);ROC curve
- 1952
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- 1002
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- 0
发布时间： - 摘要：According to the directives for the work of reference materials GB/T 15000,nicotine certified reference material was prepared.Nicotine was prepared by extraction,column chromatography and steam distillation.Its chemical structure was identified by UV，IR，MS and NMR method.Its homogeneity and stability were systematically checked.A cooperative certification was conducted by 8 laboratories，and the results of certification for nicotine were analyzed.The homogeneity and stability of the nicotine reference material were good,and the certified value was 99.12% with expanded uncertainty of 0.64% in confidence coefficient of 95%.The reference material of nicotine conforms to directives for the work of reference materials,and it could be used for method validation and quality control of regarding products.关键词：nicotine;tobacco;certified reference material;homogeneity;stability;certification
- 1877
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- 942
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发布时间： - 摘要：Adenosine deaminase(ADA)， a kind of catabolic enzymes toward nucleic acid,has a close relationship with cell immunocompetence.ADA activity is abnormal in many diseases.Therefore，more and more researchers have been focusing on research of the relationship between ADA activity and some diseases.Analysis of the ADA activity is considered to has a very important significance in clinical diagnosis and treatment of diseases.Currently，many reports about novel analysis methods of ADA activity have been published，but no relevant reviews have been reported so far.In this paper，analytical methods of ADA activity such as colorimetric，chromatography and adapter sensor methods，are summarized，which is expected to provide references for the analysis of ADA.关键词：adenosine deaminase;activity analysis;clinical test;chromatography;adapter sensor
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