最新刊期
卷 30 ， 期 7 ， 2011
- 摘要：A Nafion/Fe3O4-CdTe/CdS-myoglobin(Mb)modified glassy carbon electrode（GCE) was prepared by immobilizing Mb on the electrode surface using Fe3O4 nanoparticles and CdTe/CdS quantum dots combining the advantages of film formation ability of Nafion.Cyclic voltammetric data showed that the immobilized Mb exerted a good direct electrochemistric behavior and a good stability with a pair of well defined and nearly reversible peaks at about-0.351 V in 0.1 mol/L pH 7.0 PBS corresponding to the characteristic peaks of the Mb heme Fe（Ⅲ)/Fe（Ⅱ) redox couples.The results indicated that the microenvironment of Nafion/Fe3O4-CdTe/CdS film could promote the direct electron transfer between Mb heme Fe（Ⅲ)/Fe（Ⅱ) and GCE and provide the matrix for the immobilization of Mb.The electrocatalytic ability of the immobilized Mb to the reduction of H2O2 was also investigated and the results suggested that the modified electrode could be used as a biosensor for the detection of hydrogen peroxide with high sensitivity（30.6 mA·L/mol),low detection limit（ 0.89 μmol/L,S/N=3) and rapid response.关键词：myoglobin;Fe3O4;CdTe/CdS QDs;hydrogen peroxide;biosensor
- 2022
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- 994
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- 2
发布时间： - 摘要：A high performance liquid chromatography-mass spectrometric（HPLC-MS） method was developed for the simultaneous determination of nine phthalate esters（PAEs）in pressure-sensitive adhesive and its products.The sample was dissolved with ethyl acetate,and the PAEs were separated from polymer by using methanol. The extract was centrifugally separated for 5 min at a speed of 3 000 r/min，and the nine PAEs were separated on an Xterra Phenyl（150 mm×3.9 mm,5 μm） column by gradient elution using acetonitrile-water as the mobile phase at a flow rate of 1 mL/min，and quantitatively determined under selected ion monitoring（SIM）. Under the optimized conditions，the method showed a good linearity in the range of 0.1-10 mg/L for the nine PAEs. The limits of quantitation were 0.000 1% for DIBP，BBP，DEHP and DNOP,and 0.000 5% for DMP，DEP，DBP，DINP and DIDP. The established method was applied in the determination of three kinds of common pressure sensitive adhesives,e.g.hotmelt pressure-sensitive adhesive，solvent pressure-sensitive adhesive and emulsion pressure-sensitive adhesive. The results indicated that the recoveries ranged from 88% to 110% with relative standard deviations（RSDs） less than 6.1%. The method was reliable，sensitive and reproducible，and could meet the requirements of determination of PAEs in pressure-sensitive adhesive and its products.关键词：phthalate esters;pressure sensitive adhesive;high performance liquid chromatography-mass spectrometry
- 2401
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- 995
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- 8
发布时间： - 摘要：A long range ordered nano Au/zinc oxide(ZnO) cavities array was fabricated on indium-tin oxide electrode surface by Langmuir-Blodgett technique and sol-gel technique.The morphology of this array was characterized by scanning electron microscopy.The cyclic voltammetric(CV) behavior of nano-Au/ZnO cavities array was in accordance with that of microelectrode,and the array can be used as microelectrodes array for biosensor design.A hydrogen peroxide(H2O2) biosensor was obtained by directly immobilizing horseradish peroxidase(HRP) into nano-Au modified ZnO cavities.Direct electrochemistry of HRP on nano-Au/ZnO cavities array was investigated.In pH 7.0 phosphate buffer,the CV curve of HRP/nano Au/ZnO cavities array electrode showed a pair of stable and quasi reversible redox peaks at-0.145 V and-0.230 V.The formal potential was about-0.188 V.The result indicated that the HRP immobilized in nano-Au/ ZnO cavities still retained good electrochemistry activity.The direct electron transfer rate constant was obtained to be 2.95 s-1.The hydrophilic ZnO surface and ordered cavities structure of ZnO cavities array provided not only the suitable microenvironment for HRP to retain its bioactivity/electrochemical activity,but also the large surface area for immobilization of HRP with high load.Meanwhile,the existance of nano gold particles also enhanced the electron transfer between HRP and the modified electrode.The prepared bio sensor provided an excellent electro catalysis activity for H2O2.The calibration curve was linear in the range of 667×10-6-1.31×10-3 mol/L for H2O2 concentration with a detection limit of 73×10-7 mol/L and the apparent Michaelis-Menten constant for HRP modified electrode was 0.411 mmol/L.关键词：nano-Au;zinc oxide cavities array;microelectrode array;horseradish peroxidase;hydrogen peroxide
- 2293
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- 871
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- 3
发布时间： - 摘要：A graphene composite was prepared and coated on the copper wire as extraction fiber.A novel method was developed for the direct measurement of benzene hexachloride（BHC） pesticides residue based on solid phase microextraction（SPME）-gas chromatography equipped with electron capture detection（GC-ECD）.SPME experimental conditions，including extraction time，extraction temperature，pH and ionic strength were optimized.Under the optimized conditions，the self made fiber showed superior extraction efficiencies for α-BHC，β-BHC，γ-BHC and δ-BHC in real water samples with recoveries of 76%-120%.The relative standard deviations（RSDs） of single fiber were in the range of 4.8%-7.5%,and the RSDs between different fibers were 4.1%-9.1%.Good linearities were obtained in the range of 0.5-200 μg/L for four BHCs with detection limits of 0.04-0.15 μg/L.The results indicated that the established method was simple，rapid and sensitive，and was suitable for the determination of benzene hexachloride pesticide residues in water samples.关键词：graphene;solid-phase microextraction;gas chromatography;benzene hexachloride pesticides
- 2992
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- 1090
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- 8
发布时间： - 摘要：A label free electrochemical biosensor was developed for the detection of p53 tumor suppressor gene using hairpin DNA as nucleic acid probe and RuHex as hybridization indicator,based on the specific recognition of hairpin DNA and the electrostatic interaction between［Ru（NH3）6］3+ and DNA. The experimental results indicated that this electrochemical sensor can sensitively detect target DNA in 10 μmol/L RuHex solution with a detection limit of 2.5 nmol/L. According to the difference of the electrochemical signals,the sensor could discriminate the complete complementary DNA from single-mutation DNA and the random DNA. The hybridization efficiency of hairpin DNA and the target sequences with different mutation sites was investigated and the results showed that the mutate sites affected DNA hybridization efficiency. The prepared sensor showed the advantages of sensitivity,selectivity,label free and simplicity.关键词：hairpin DNA;RuHex;p53 gene;electrochemical biosensor
- 1912
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- 1136
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- 4
发布时间： - 摘要：Combined with purification of silica gel column and determination by GC-MS,the extraction effects of microwave-assisted solvent extraction（MSE）,soxhlet extraction（SE） and ultrasonic extraction（UE） for polycyclic musk were studied.The extraction conditions of MSE were optimized.The optimal extraction conditions were as follows:extraction solvent:30 mL acetone-hexane（1∶1）,extraction time:20 min,temperature:120 ℃.Under the optimized conditions,the calibration curves of galaxolide(HHCB) and tonalide(AHTN) were liner in the range of 10-1 000 μg/L,with correlation coefficients of 0.999 5 and 0.996 4,respectively.The average recoveries of HHCB and AHTN were 84% and 89%,respectively,with RSDs of 11.2% and 9.2%.The detection limits were 0.71 μg/kg for HHCB and 0.68 μg/kg for AHTN.The result indicated that,compared with other extraction methods,the MSE method had obvious advantages in extraction effect,extraction time and organic solvent consumption, and was the best method for the extraction of polycyclic musk in soil at this stage.关键词：sample preparation and pretreatment;microwave-assisted solvent extraction;polycyclic musk;soil
- 2475
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- 1031
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- 1
发布时间： - 摘要：The binding reactions between antimalarial agent,e.g.artemisinin（ART）or dihydroartemisinin（DHA）,and drug-metabolizing enzyme CYP2B6 were studied by fluorescence quenching spectroscopy at simulated physiological conditions. The structural information of CYP2B6 during their interactions was investigated by synchronous fluorometric method.The results showed that,for both reactions of ART with CYP2B6 and DHA with CYP2B6,the main quenching mechanism was static quenching at temperature range of 296-303 K,and turned to static quenching mixed with dynamic quenching while the temperature increased to 303-310 K.At a physiological temperature of 310 K,the bonding capability of DHA and CYP2B6 was stronger than that of ART and CYP2B6.The main bonding formation of ART to CYP2B6 system was hydrogen bond by Van Der Waals force at the temperature range of 296-303 K,and then changed to hydrophobic force when the temperature stepped up to 303-310 K.However,the main bonding force between DHA and CYP2B6 was electrostatic force at 296-303 K and changed to hydrogen bond by Van Der Waals force when the temperature grew to 303-310 K.All of the reactions were spontaneous thermodynamics reactions.And the synchronous spectra showed that both the bonding sites of ART to CYP2B6 and DHA to CYP2B6 were near to the tryptophane residue of CYP2B6,and the bonding site of DHA was closer than that of ART to the tryptophane residue.Meanwhile,both ART and DHA had little influence on the conformation of CYP2B6 at room temperature（298 K）.关键词：fluorescence spectroscopy;synchronous fluorescence spectroscopy;artemisinin;dihydroartemisinin;CYP2B6
- 1979
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- 933
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- 1
发布时间： - 摘要：Effects of DNA damage induced by aconitum were studied by high performance liquid chromatography with ultraviolet detection（HPLC-UV）.The working conditions were as follows:column:Agilent TC-C18（4.6 mm×150 mm，5 μm）;detection wavelength:260 nm;mobile phase:50 mmol/L KH2PO4/K2HPO4 buffer（pH 5.5）-methanol（9∶1）;flow rate:0.8 mL/min.Under the optimal conditions,the calibration curve was linear in the concentration range of 1.78-353 μmol/L for 8-hydorxy-2′-deoxyanosine（8-OHdG）,with a correlation coefficient of 0.999 9.The detection limit（S/N=3） was 0.35 μmol/L.The mean recovery was 102%.The method was successfully applied to analyze the levels of 8-OHdG in the blood and urine of rabbit exposed to aconitum by mouth injection for five consecutive weeks.The results showed that aconitum can cause the oxidative DNA damage and the formation of 8-OHdG after a long-term administration of rabbit,which indicated that aconitum contains the potential genotoxicity.关键词：aconitum;DNA damage;8-hydorxy-2′-deoxyanosine（8-OHdG）;genotoxicity
- 2606
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- 885
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- 3
发布时间： - 摘要：An ultra performance liquid chromatography-tandem mass spectrometric（UPLC-MS/MS） method was developed for the rapid determination of six alkaloids in tobacco.The sample pretreatment and parameter separation conditions were optimized.The samples were extracted with deionized water,and separated on UPLC BEH C18 chromatographic column.The mass spectrometer with electrospray in positive ionization was operated under multiple reaction monitoring（MRM）mode.Six alkaloids was quantified by the isotope internal standard method to avoid matrix effects.The result indicated that,the calibration curves of six alkaloids were in the range of 0.1-8 000 μg/L.The spiked recoveries ranged from 87% to 115% with relative standard deviations of 1.9%-9.7%.The limits of detection ranged from 50 μg/kg to 1 250 μg/kg.This method was simple,accurate and reproducible,and could be used for the rapid analysis of six alkaloids in batches of tobacco samples.关键词：UPLC-MS/MS;ultrasonic extraction;tobacco;alkaloids
- 2354
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- 1023
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- 7
发布时间： - 摘要：A fluorescent latex immunochromatographic assay for the detection of ractopamine residues in pork was established based on competition principle.Fluorescent latex particles were marked with anti-RAC monoclonal antibody(McAb）,the conjugate was sprayed onto the conjugate pad.Then goat anti-mice IgG and the artificial antigen RAC-BSA were prepared and jet-positioned onto nitrocellulose(NC）membrane as the control line(C)and the test line(T),respectively.Sample pad,conjugate pad,nitrocellulose membrane and absorbent paper were assembled in turn and cut into detecting strips.The more the RAC exists in the sample,the more effectively it would bind to the limited amount of fluorescent latex particles-marked anti-RAC McAb competed with RAC-BSA,and the test line would be darker simultaneously under UV-light.The brightness of the fluorescence band could indicate a semi-quantitative result intuitively.The minimum limit of the strips could reach 0.5 μg/L for the detection of RAC in pork sample，without any cross-reactions with clenbuterol(CL） and salbutamol(SAL）.The fluorescent latex immunochromatographic assay could be used in the rapid and simple screening test for ractopamine residues in pork with its low cost, high stability and sensitivity.关键词：ractopamine;fluorescent latex particles;immunochromatography assay(ICA）;pork
- 2722
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- 1058
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- 10
发布时间： - 摘要：A rapid,accurate nuclear magnetic resonance（NMR) spectrometric technique was developed for the qualitative and quantitative analysis of multicomponent surfactant combinations.The efficient methods for the separation and identification of multicomponent surfactant mixtures were investigated in detail.The main characteristic peaks in the NMR spectra of surfactants were assigned,and the surfactant contents were obtained by NMR signal component analysis.The experimental results confirmed that NMR spectroscopy can be used to quantify the structures of surfactants in multicomponent systems.关键词：surfactant;combinations;NMR
- 2235
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- 932
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- 2
发布时间： - 摘要：A gas chromatography-mass spectrometric（GC-MS） method was developed for the determination of 2-ethoxyethanol, 2-methoxyethyl acetate, styrene, 2-ethoxyethyl acetate, cyclohexanone, bis（2-methoxyethyl）ether, 1,3,5-trimethylbenzene, nitrobenzene and isophorone in toys. The experimental conditions were optimized.Toy sample was extracted with appropriate solvent and followed by centrifugalization,then purified with an Envi-carb solid-phase extraction column.The extract was concentrated, and then determined by GC-MS with the external standard method.The calibration curves were linear in the range of 0.5-100 mg/L for 2-ethoxyethanol, 0.05-100 mg/L for styrene, 1,3,5-trimethylbenzene and isophorone, and 0.1-100 mg/L for rest of the targeted compound.The correlation coefficients were all not less than 0.999 5 and the limits of quantitation of 9 organic compounds ranged from 0.1 mg/kg to 1.0 mg/kg.The average recoveries for eight kinds of the substances at three spiked concentration levels ranged from 70% to 94%, except for 1,3,5-trimethylbenzene with low recovery.The relative standard deviations（RSDs） of the method were in the range of 2.8%-6.5%.The method is accurate and simple, and is suitable for the analysis of 9 organic compound residues in various toys.关键词：gas chromatography-mass spectrometry（GC-MS）;organic residues;toys
- 2401
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- 1079
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- 9
发布时间： - 摘要：A highly sensitive label free electrochemical immunosensor was developed for the determination of human IgG based on a gold electrode modified with GNPs and carbon nanotubes（CNTs） incorporated with chitosan composite and the IgG antibody was directly absorbed on the modified electrode surface. The electrochemical behaviors of the modified electrode were investigated by cyclic voltammetry（CV）and AC impedance.The influence of electrolyte pH on immunosensor was studied by differential pulse voltammetry（DPV）. A good linearity was obtained between response current and concentration of human IgG antigen in the range of 0.05-455 μg/L，with a correlation coefficient(r2) of 0.991 1. The detection limit（S/N=3） was 0.01 μg/L. Compared with the traditional methods，the immunosensor exhibited the advantages of simple preparation，high sensitivity and long-term stability without any consumption of reagent for signal amplification.关键词：chitosan;carbon nanotubes;gold nanoparticles;label-free;antibody;human IgG;immunosensor
- 2272
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- 925
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- 3
发布时间： - 摘要：A novel method was developed for the simultaneous determination of three trace phenylurea herbicides,such as isoproturon,metobromuron and monuron in environmental water,by liquid phase microextraction（LPME）coupled with high performance liquid chromatography（HPLC）.The effects of differerent extraction and measuring conditions on detection were investigated.The optimal experimental conditions were as follows:organic solvent:6 mL octanol,drop volume:3 μL,stirring speed:450 r/min,extraction time:30 min.Under the optimal conditions,the enrichment factors of isoproturon,metobromuron and monuron were 510,490 and 350,respectively.There was a good linearity between peak area and concentration of three herbicides in the range of 0.5-800 μg/L,with correlation coefficient of 0.995 8-0.998 3.The detectioin limits of three phenylurea herbicides ranged from 0.2 μg/L to 0.4 μg/L.The spiked recoveries of three herbicides from environmental water samples were in the range of 62%-92% with relative standard deviations（RSDs） no more than 7.7%.The method showed the advantages of sensitivity,simplicity and fastness for the use of very small amounts of organic solvent,and could meet the requirements of the determination of trace phenylurea herbicides in environmental water samples.关键词：liquid phase microextraction（LPME）;high performance liquid chromatography（HPLC）;environmental water sample;phenylurea herbicide
- 2022
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- 1067
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- 4
发布时间： - 摘要：A novel approach to producing core/shell quantum dots（QDs） of ZnS∶Mn/ZnS was developed by nucleation doping strategy using thioglycolic acid（TGA） as stabilizer. The producing mechanisms of fluorescence and room temperature phosphorescence（RTP） were studied. The fluorescence,RTP analysis methods were developed for the determination of DNA with functionalized water soluble ZnS∶Mn/ZnS QDs as a labeled probe,based on the fluorescence,RTP enhancing of the QDs in the presence of DNA,respectively. The influences of experimental conditions,such as concentration of QDs,amount of EDC/NHS and reaction time,were investigated. The results showed that,under the optimal conditions,the calibration curves of both the methods were linear in the range of 50-600 μg/L for ctDNA. The detection limits for the fluorescence and RTP method were 39.6,28.5 μg/L,respectively. The recoveries were in the range of 98%-104% and 99%-101% with relative standard deviations（n=25） for 300 μg/L ctDNA of 3.1% and 2.3%,respectively. The methods were simple,safe and sensitive for the determination of trace DNA.关键词：ZnS∶Mn/ZnS;fluorescence probes;room temperature phosphorescence;DNA
- 2158
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- 953
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- 2
发布时间： - 摘要：An optical approach was developed for the detection of Cd2+ based on ion imprinted polymer membrances as sensing receptors.The polymer was synthesized with cadmium ions as a template and 2-naphthyl acrylate as both the fluorescence tag and a complex-forming agent.The free radical polymerization was performed within PVDF films and was initiated by 2,2′-azobisisobutyronitrile at 65 ℃ in dimethyl sulfoxide.The polymer showed a high selectivity for cadmium ions.The calibration curve was linear over the Cd2+ concentration range of 1-9 μmol/L with a detection limit of 5.5×10-7 mol/L.Compared with that by the ICP-MS method，the results by this method had no obvisous difference.The RSDs（n=10） of the polymer for Cd2+ was 2.3%，and the recoveries for Cd2+ in spiked river water were in the range of 97%-100%.关键词：metal ion imprinted polymer;surface molecular imprinted technique;fluorescence sensor;cadmium ion;2-naphthyl acrylate
- 2211
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- 842
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- 6
发布时间： - 摘要：To establish a method for the determination of chlorphenamine maleate in chlorphenamine maleate tablet by large volume injection-acetonitrile salt stacking-MEKC.The determination conditions containing concentrations of acetonitrile and sodium chloride in sample matrix on separation efficiency were optimized.The result indicated that a best separation of chlorphenamine maleate was obtained on an uncoated fused silica capillary column (50 cm×50 μm,effective length 36 cm） by using the background electrolyte containing 12 mmol/L sodium tetraborate,50 mmol/L boric acid and 50 mmol/L SDS,and 10% methanol at pH 9.1 ,70% acetonitrile-200 mmol/L sodium chloride(NaCl）in standard and sample matrix at 25 ℃. The detection wavelength was set at 215 nm,sample injection voltage was 20 kV and injection time was 120 s. Under the optimum conditions,chlorphenamine maleate was separated in 14 min with theoretical plate number of 677 240.The relative standard deviations(RSDs） for peak area were less than 4%. The calibration curve was linear in the range of 0.398-6.368 mg/L for chlorphenamine maleate with a detection limit (S/N=3） of 8.95 μg/L. The spiked recoveries were in the range of 93%-102%.Compared with that of the normal MEKC method detection limit (82.3 μg/L）,the sensitivity of the proposed method was increased by 10 times.关键词：acetonitrile-salt stacking;micellar electrokinetic chromatography(MEKC);large volume injection;chlorphenamine maleate
- 1948
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- 834
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- 2
发布时间： - 摘要：A simple and rapid colorimetric method was developed for the detection of Hg2+ based on the specific thymine T -Hg2+ -T structure and gold nanoparticles.A tweezers like duplex DNA，containing 9 T-T mismatches in the end，was designed.The mismatched thymines in the tweezers like dsDNA could not form helix structure,which could attach to AuNPs and effectively prevent AuNPs from salt induced aggregation.While in the presence of Hg2+ ions，the T-Hg2+-T coordinations would lead these thymines to form the structures of helix.The AuNPs were less well-protected thus aggregated at the same salt concentration，accompanied by color changing from red to blue.The maximum absorption wavelength of AuNPs solution would change from 520 nm to 620 nm.Under the optimal conditions，the absorption ratio A620/A520 was proportional to Hg2+ concentration in the range of 5.0×10-8-5.0×10-7 mol/L with a detection limit of 3.0×10-8 mol/L.The interferences from selected inorganic ions were investigated.The result indicated that the sensor showed a good selectivity for Hg2+，and other metal ions （e.g. Ca2+，Mg2+） had no significant interferences.The proposed method was simple and rapid，and could be used in the detection of Hg2+ within 1 min.关键词：mercury ion;T-Hg2+-T;gold nanoparticle;colorimetry;rapid detection
- 2439
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- 897
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- 8
发布时间： - 摘要：A liquid chromatography-mass spectrometric(LC-MS） method was established for the determination of six estrogens in drinking water.The sample was extracted with acetonitrile，enriched by Oasis HLB solid phase extraction column，and then analyzed by LC-MS.Under the optimal conditions，good linearities were obtained in the range of 5-100 μg/L for six estrogens with correlation coefficients of 0.994-1.000.The detection limits for 6 estrogens were all 0.1 μg/L.The recoveries at three spiked levels of 0.10，25,50 μg/L were between 85% and 95% with relative standard deviations less than 10%.With the advantages of high sensitivity and simple sample preparation without matrix interference,the method was suitable for the analysis of the estrogens in drink water.关键词：drinking water;estrogen;liquid chromatography-mass spectrometry(LC-MS）
- 2944
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- 1020
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- 5
发布时间： - 摘要：A method for the isolation and purification of （-)-epigallocatechin-3-（3″-O-methyl)gallate（EGCG3″Me) from crude extract sample was firstly developed by high speed countercurrent chromatography(HSCCC).The results showed that HSCCC had a two phase solvent system composing of water-methanol-ethyl acetate-hexane（5∶2∶9∶1,by volume) on a preparative scale.The upper phase was used as the stationary phase,and the lower phase was used as the mobile phase.The revolution speed was 700 r/min,the flow rate was 2.0 mL/min and the detection wavelength was set at 254 nm.Under the optimized conditions,EGCG3″Me can be well isolated.The purity of EGCG3″Me detected by high performance liquid chromatography was more than 90%,and the yield of EGCG3″Me by HSCCC was 76.53%.关键词：EGCG3″Me;high speed countercurrent chromatography;isolation and purification;high performance liquid chromatography
- 2028
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- 856
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- 1
发布时间： - 摘要：An analytical method based on ultrasound-assisted extraction technique followed by gas chromatography-mass spectrometry analysis was developed for the determination of hydroquinone in sediment samples.The operating conditions of the extraction process including the solvent type,the power of ultrasound and the extraction time were optimized.The result indicated that,under the optimal conditions,the recoveries of hydroquinone ranged from 85% to 92% with relative standard deviations of 3.0%-7.2%.The calibration curve for hydroquinone was linear within the range of 0.05-10 mg/L.The detection limits for hydroquinone were 12.88 ng/g.This method was rapid,simple and sensitive,and was suitable for the rapid determination of hydroquinone in sediment samples.关键词：Ultrasound-assisted extraction;sediment;hydroquinone;gas chromatography-mass spectrometry
- 2231
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- 818
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- 0
发布时间： - 摘要：A sensitive high performance liquid chromatography tandem mass spectrometric（LC-MS/MS) method was developed for the determination of perchlorate in milk.The perchlorate residue in milk was extracted with 1% acetic acid-acetonitrile（1∶4,by volume) and the protein of milk was precipitated by acetonitrile.The extract was centriged at 6 000 r/min for 20 min，and the supernatant was cleaned up with 0.2 μm nylon filter,On-Guard Ⅱ RP column,On-Guard Ⅱ Ag column and On-Guard Ⅱ Ba column in turns.The separation of perchlorate was carried out on a C12（Synergi 4u MAX-RP80A) by gradient elution using 1% formic acid（A)-methanol（B)as mobile phase with flow rate of 0.3 mL/min.The perchlorate was analyzed by tandem mass spectrometry with negative ion electrospray under multiple reaction monitoring（MRM) mode by selecting m/z 98.9/82.8 as qualitative ions．The extract was quantified by the external standard method.The result indicated that a good linearity was obtained for perchlorate concentration in the range of 0.1-1 000 μg/L.The average recoveries of perchlorate from 3 kinds of milk in market at three concentration levels of 1.0,5.0,10 μg/L ranged from 84% to 94% with RSDs of 1.2%-1.7%.The quantitation limit（LOQ) and detection limit（LOD) of perchlorate were 0.1 μg/L and 0.03 μg/L,respectively.The method is suitable for the determination and confirmation of perchlorate in milk with good repeatability and high sensitivity.关键词：high performance liquid chromatography tandem mass spectrometry（LC-MS/MS);perchlorate;milk;residue analysis
- 2441
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- 3
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- 9
发布时间： - 摘要：As a kind of chromatographic columns developed rapidly in recent years，the monolithic columns have been widely applied in biological sample analysis for their high resolution，low-cost preparation，long service life，good stability and other advantages. The recent development of organic polymer monolithic columns was reviewed. The preparation process，raw materials for preparation （monomer，crosslinker，initiator and porogen） and initiation methods were outlined. In addition，the modified organic polymer monolithic columns made up of organic polymer monolith with the derived surface，monolithic column combining the nano-materials with organic polymer monolith and organic-inorganic hybrid monolith were discussed according to the ways of modification technology. The application of organic polymer monolithic columns in the pretreatment of biological sample were summarized，especially in capillary electrochromatography（CEC），microcolumn liquid chromatography（μ-HPLC） and micro-analysis system（μ-TAS）. Finally，the trends and future perspectives of organic polymer monolithic columns were outlined.关键词：organic polymer monolithic columns;modification;application;development;review
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