最新刊期
卷 35 ， 期 1 ， 2016
- 摘要：Fe3O4@SiO2-NH2 magnetic nanoparticles composites were successfully synthesized by three-step method，and used as adsorbents for the extraction and analysis of seven typical perfluorinated compounds（PFCs） in water solution. In combination with ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry（UPLC-MS/MS），a method to determine seven typical perfluorinated compounds in water was established. The synthesized material was characterized by TEM，SEM and FT-IR. The influencing factors including desorption solvent，volume of desorption solvent，desorption time，extraction time and pH value of solution were investigated. The result showed that amino was successfully modified on the surface of Fe3O4@SiO2 magnetic nanoparticles. Fe3O4@SiO2-NH2 magnetic nanoparticles composites exhibited a good extraction effect on the target perfluorinated compounds，and the optimum extraction efficiency was achieved as follows： extraction time： 20min，desorption solvent: 3mL×4 0.28% ammonia methanol solution，desorption time： 5min，and pH value： 5.0.Under the optimum conditions，the calibration curves of seven perfluorinated compounds were linear in the range of 1-500ng/L,with limits of detection of 0.2-0.5ng/L.The method was applied in the detection of target perfluorinated compounds in real water with spiked recoveries no less than 82.0%.关键词：Fe3O4@SiO2-NH2;perfluorinated compounds;ultra-high performance liquid chromatography tandem mass spectrometry（UPLC-MS/MS）;environmental water samples
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发布时间： - 摘要：Using modified multi-walled carbon nanotubes as sorbent in modified QuEChERS method,a rapid determination method of 24 organochlorine and pyrethroid pesticides in tea by gas chromatography-mass spectrometry was developed. Pesticides residues in tea were extracted with a hexane-acetone(2∶1) mixture,and cleaned up with hydroxylated multi-walled carbon nanotubes(MWCNTs-OH) and primary-secondary amine(PSA) as dispersive solid-phase extraction sorbent. After centrifugation and filtration,the target compounds were analyzed by gas chromatography-mass spectrometry,and quantified by the external standard method. Effects of different sorbents and extraction solvents, amount of hydroxylated multi-walled carbon nanotubes on the determination of organochlorine and pyrethroid pesticides residues were investigated. Under the optimal conditions, the calibration curves were linear in the range of 0.01-0.50mg/kg.Tests of recoveries were made by the addition of mixed standards to blank tea sample at three concentration levels, and the recoveries were in the range of 78.6%-109.6% with relative standard deviations(RSDs, n=5) of 2.1%-9.3%.The quantitation limits of method were in the range of 0.002-0.050mg/kg.The method is simple, rapid, sensitive and cheap, and could meet the requirements for the detection of organochlorine and pyrethroid pesticides in teas, particularly suitable for the application in small laboratories and enterprises.关键词：hydroxylated multi-walled carbon nanotubes;dispersive solid-phase extraction;gas chromatography-mass spectrometry;tea;organochlorine pesticides;pyrethroid pesticides
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发布时间： - 摘要：A new mono-ureado β-cyclodextrin-bond ordered mesoporous SBA-15 chiral stationary phase(UCDP) was prepared and packed into the column. With common methanol-water as mobile phase,the chiral pesticide diniconazole enantiomers was successfully separated by using UCDP. Effects of mobile phase composition and temperature on the chiral separation were investigated. The optimized chromatographic conditions for diniconazole enantiomers were as follows: mobile phase: methanol-water(40∶60),flow rate: 0.5mL/min,column temperature: 25℃,detection wavelength: 248nm.Based on the above separation conditions, an HPLC method for the rapid determination of diniconazole enantiomer residues in pear was established. The pear samples were extracted with acetonitrile and purified with amino solid extraction column, and determined on UCDP in the above conditions. The good linear relationships for two enantiomers were observed in the range of 0.5-125μg/mL.The average recoveries of the analytes in pear samples at two spiked concentration levels of 1.25μg/mL and 5.0μg/mL were in the ranges of 92.0%-94.4%for R-enantiomer, and 91.2%-92.8% for S-enantiomer, respectively. According to the signal-to-noise of 3(S/N=3),the detection limits of diniconazole enantiomers were 0.02μg/mL. The UCDP preparation method is simple, and the stationary phase with urea group is stable. The developed method is rapid, accurate and reproducible, and has a good application prospect in the determination of chiral pesticide residues in fruits and vegetables.关键词：high-performance liquid chromatography(HPLC);cyclodextrin-based chiral stationary phase;diniconazole enantiomer;chiral pesticides;food safety
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发布时间： - 摘要：A novel molybdenum disulfide-self-doped polyaniline(MoS2-SPAN) nanocomposite was successfully prepared by liquid exfoliation method. In the process of ultrasonication, the negatively charged SPAN diffused and intercalated in the MoS2 nanosheets to form a three dimensional-structured nanocomposite,due to the strong π-π* stacking interaction and electrostatic repulsion.The as-prepared MoS2-SPAN nanocomposite was characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR) and electrochemical method, which indicated that this nanocomposite had the advantages of a large effective area,a great deal of electroactive species and high stability.The electrochemical behavior of lead ions at MoS2-SPAN nanocomposite modified glassy carbon electrode(MoS2-SPAN/GCE) was investigated by differential pulse anodic stripping voltammetry(DPASV),and the electrochemical detection conditions for lead ions were also optimized. The results showed that the MoS2-SPAN nanocomposite possessed good conductivity and excellent adsorption performance for lead ions,and the MoS2-SPAN/GCE could realize the highly sensitive electrochemical detection of lead ions due to the large surface area and the good synergistic effect of MoS2-SPAN nanocomposite. Both, the MoS2-SPAN/GCE exhibited good linear relationships between peak currents and concentrations of Pb2+ in the ranges of 0.1-10μg/L and 10-100μg/L, and the limit of detection(S/N=3) was 2.87×10-8g/L.Besides,this electrochemical method based on MoS2-SPAN nanocomposite had an excellent repeatability and a good anti-interference ability, and it could be applied in the determination of lead in actual water sample.关键词：molybdenum disulfide;self-doped polyaniline;synergistic effect;lead ions;high sensitivity detection
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发布时间： - 摘要：A rapid method for the simultaneous determination of fat-soluble vitamins A and D in vitamin A and D pharmaceutical was developed using online two-dimensional liquid chromatography（2D-LC）.A type of polar embedded C18 was selected as the second dimension separating column according to system suitability testing requirement.C8 was chosen as first dimension separating column because fat-soluble substance was rich in matrix and a better orthogonality could meet with polar embedded C18 according to hydrophobic subtraction model.Sample solution after extracted with methanol without further purification was injected into liquid chromatography directly.The purification of vitamin D and quantification of vitamins A acetate were accomplished simultaneously in one dimensional separation using the right pump of Dual Gradient LC（DGLC） with methanol-acetonitrile-water as mobile phase.Vitamin D and pre-vitamin D were separated and quantified in two dimensional column by using the left pump of DGLC.The eluted target from the first dimensional column（1-D column） was collected by a 500 μL loop and then taken into the second dimensional column（2-D column） by the left pump of DGLC with high aqueous mobile phase.The cutting window could be confirmed by the retention time of target in one dimensional separation.Detection wavelengths of 325 nm and 264 nm were set at the diode-array detector.Vitamin A,vitamin D and pre vitamin D were quantified simultaneously and automatically in one injection by the external standard method.The results showed that the good linearities（r>0.999） for vitamin A and vitamin D could be obtained in the range of 0.1-250mg/L and 0.02-50.0mg/L,respectively.The recoveries of vitamin D ranged from 89.9% to 98.9%.The RSDs for precision and reproducibility are 0.48% and 1.2%,respectively.All the validating results indicated that vitamins A and D in pharmaceutical could be quantified rapidly and accurately by this method.关键词：two-dimensional liquid chromatography（2D-LC）;online separation;vitamin D;vitamin A;pre-vitamin D;vitamin A and D drops
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发布时间： - 摘要：An analytical method for the simultaneous determination of gefitinib and its related substances in raw material drugs was developed by using reversed-phase high performance liquid chromatography(RP-HPLC).The analysis was carried out on a Phenomenex Gemini C18 column(250 mm×4.6 mm，5 μm) with acetonitrile-0.15%ammonium acetate(pH 8.5) as mobile phase at a flow rate of 1.0 mL/min,detection wavelength of 255 nm and column temperature of 40 ℃ in a gradient elution mode.Under the optimized conditions,gefitinib and its related substances had good linearities in the range of 0.012 0-4.202 μg/mL (r>0.999 0).Their detection limits were between 0.001 7 and 0.094 1 μg/mL.The average recoveries ranged from 99.7%to 100.9%with relative standard deviations (RSDs) of 0.06%-0.70%.The method was applied in the determination of gefitinib and its related substances in raw material drugs with satistactory results,and the method was sensitive,accurate,and was reliable for the quality control of gefitinib in drugs.关键词：reversed-phase high performance liquid chromatography(RP-HPLC);raw material drug;gefitinib;related substances;quality control
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发布时间： - 摘要：A new method was established for the simultaneous determination of 10 quinolone(QN) residues in animal-originated foodstuffs by ultrafiltration tube cleaning with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).After extraction with acetonitrile (containing 1%acetic acid),the extract was purified with 50 mL Millipore ultrafiltration tube (Molecular Weight Cut-Off，MWCO:3 kD),and then the centrifugal liquid was evaporated to dryness under a stream of nitrogen,and redissolved.The analytes were separated on a Waters Xbridge C18 column using 0.1%formic acid-acetonitrile as mobile phase.The identification and quantification of 10 quinolone residues were carried out under positive electrospray ionization (ESI+) in multiple reaction monitoring (MRM) mode，the quantification analysis was performed by the external standard method.The calibration curves showed good linearities in the range of 5.0-100 μg/kg for all QNs.The limits of detection for all QNs were in the range of 0.15-0.75 μg/kg,and the limits of quantitation were 0.49-2.59 μg/kg.The recoveries of these analytes varied from 71.4%to 85.9%at spiked levels of 5.0,10,50 μg/kg,with relative standard deviations of 3.9%-10.7%.This method was simple,rapid,sensitive and reproducible,and could be applied in the determination of 10 quinolone residues in anima-originated foodstuffs．关键词：ultrafiltration tube;high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS);animal-originated foodstuffs;quinolones
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发布时间： -
Study on Graphitic Carbon Nitride Modified Electrochemical Sensors for Determination of Nitrobenzene
摘要：In this study,graphitic carbon nitride(g-C3N4) was synthesized by thermal condensation with melamine,and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and infrared spectroscopy.Graphitic carbon nitride was dispersed in Nafion solution by ultrasound to prepare suspension liquid which was modified onto the surface of a glassy carbon electrode(GCE) to prepare an electrochemical sensor(g-C3N4/ Nafion /GCE) for nitrobenzene.The voltammetric behaviours of nitrobenzene at the g-C3N4/ Nafion /GCE were studied by cyclic voltammetry and square-wave voltammetry(SWV).Under the optimal conditions,the cathodic peak current of nitrobenzene showed a highly linear increase with nitrobenzene concentrations over the range of 4.0×10-6-6.0×10-4 mol/L with a correlation coefficient(r) of 0.999 8.The detection limit was 4.0×10-7 mol/L.The concentration values in real water samples were determined by the national standard method.No SWV response corresponding to nitrobenzene was observed when the real water samples were analysed.Simulated water samples therefore were prepared,and standard-additions method was adopted to estimate the recorvery.The recoveries at two spiked concentration levels were 102.1%and 99.9%,respectively.No obvious differences were found between the proposed method and the gas chromatographic method.关键词：carbon nitride;nitrobenzene;square wave voltammetry;electrochemical sensor- 2220
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发布时间： - 摘要：A method was developed for the determination of patulin in fruit products by isotope dilution with high performance liquid chromatography tandem mass spectrometry（HPLC-MS/MS）.The clear juice was directly purified and enriched with ProElut PXA.Besides,the cloud juice,solid liquid and solid samples were primarily hydrolyzed with pectinase,then extracted with ethyl acetate and concentrated,redissolved with acetic acid solution（pH 4.0）,and purified and enriched with ProElut PXA.The chromatographic separation was performed on a Waters HSS T3 column（2.1 mm×100 mm，1.8 μm） by gradient elution with acetonitrile-water as mobile phase.The patulin was detected by MS with electrospray negative ionization（ESI） under multiple reaction monitoring（MRM） mode.Accurate determination was achieved using isotope as the internal standard.Results showed that the calibration curve of patulin was linear in the range of 5-250 ng/mL with correlation coefficients greater than 0.999.The limits of quantitation（LOQ） of this method were 2.0 μg/kg for apple juice and 5.0 μg/kg for apple wine and haw.The recoveries of patulin at low,medium and high spiked concentration levels were in the range of 90.6%-110.1% with relative standard deviations of 1.4%-3.9%.The proposed method was proved to be a practical method which could completely satisfy the standard requirement GB 2761-2011 for detection of patulin in fruit products including apple juice,apple wine and haw products.In conclusion,this method was reliable,accurate and sensitive,and could be used for the analysis of patulin in fruit products.关键词：patulin;high performance liquid chromatography tandem mass spectrometry（HPLC-MS/MS）;isotope dilution;fruit products
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发布时间： - 摘要：A rapid method was developed for the simultaneous determination of synthetic musks and organophosphate esters(OPs) in sediment/sludge,based on ultrasonic-assisted extraction,solid phase extraction(SPE) and the subsequent analysis by gas chromatography-mass spectrometry(GC-MS).In this study,different solvents were investigated and optimized,and thus acetone and acetonitrile-water(1∶3) were chosen for the extraction of analytes.Two potential factors(the matrix effect and aging effect) influencing recoveries of the target compounds of the analgtes were also studied.Under the optimized conditions,13 analytes including 9 widely used OPs and 4 synthetic musks were extracted and analyzed,and the results indicated that acceptable recoveries of the analytes were achieved in the range of (27%±12%)-(117%±9%),from sediment,sludge and pre-extracted sediment at different spiked concentrations.关键词：organophosphate esters;synthetic musks;ultrasonic-assisted extraction;solid phase extraction;gas chromatography-mass spectrometry(GC-MS)
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发布时间： - 摘要：A method of ion chromatography（IC） with suppressed conductivity detection for the simultaneous determination of F-，Cl-，Br-，NO-3，SO2-4 anions in motor gasoline and diesel oil was established.After ultrasonic extraction with 90% methanol aqueous solution and centrifugation,the sample in aqueous phase was purified with 0.22 μm hybrid filter membrane,and then quantitatively analyzed by the external standard method using IC instrument with 15 mmol/L KOH as the eluent.The effects of concentration and flow rate of the eluent,and concentration of methanol aqueous solution on the detection of five anions were investigated.The linear relation of five anions were good in the range of 0.50-20.00 mg/L and all the linear correlation coefficient were not less than 0.999.The average recoveries of target anions in gasoline were in the range of 87.6%-109.7% with relative standard deviations（RSDs） of 0.4%-3.5%,and the average recoveries of target anions in diesel oil were 86.8%-110.0% with RSDs of 0.1%-2.9%.The limits of detection（LOD） of five anions were in the range of 0.01-0.04 mg/kg.This method avoids the high requirements on the instrument,complicated and time-consuming pretreatment process.It was simple,reliable and sensitive,and was suitable for the simultaneous detection of trace inorganic anions in motor gasoline and diesel oil.关键词：ion chromatography（IC）;inorganic anions;liquid phase extraction;gasoline;diesel oil
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发布时间： - 摘要：A method for the simultaneous determination of 3 β-agonists in animal manure was studied by ultra high performance liquid chromatography coupled with electrospray ionization triple-quadruple tandem mass spectrometry(UPLC-ESI MS/MS).The drugs were cleaned up with perchloric acid solution after enzymolysis and adjusting pH to alkaline.The purified analyte was extracted with ethyl acetate.The extract was evaporated to dryness under nitrogen,and reconstituted in mobile phase solution.The target compounds were confirmed and quantified by UPLC-ESI MS/MS with the internal standard method.Under the optimal conditions,the calibration curves of 3 β-agonists showed good linearities in the range of 0.5-20.0 μg/L with correlation coefficients more than 0.998.The average recoveries of 3 β-agonists were in the range of 80.3%-110.2%,and the relative standard deviations(RSDs) were 3.0%-7.7%.The limits of detection(S/N=3) ranged from 0.04 μg/kg to 0.07 μg/kg.关键词：ultra high performance liquid chromatography coupled with electrospray ionization triple-quadruple tandem mass spectrometry(UPLC-ESI MS/MS);animal manure;β-agonists;internal standard method
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发布时间： - 摘要：A new ionization mass spectrometry method was established for the detection of trace cadmium in water.Microwave plasma torch(MPT) as the ion source,combined with a mass spectrometer can be directly used to analyze water samples without any sample pretreatment.Water sample was transformed into aerosol by directly atomizing nebulizer.The aerosol after heating-cooling cycles and drying of concentrated sulfuric acid,was introduced into the plasma through the MPT central conduit,generating ions detected with quadrupole mass spectrometer(QMS) to afford cadmium MPT features MS.Quantitative analysis was carried out based on the characteristics of cadmium mass.The results showed that the signal intensity 114Cd had a good linearity with the solution of cadmium ion concentration within 300-3 000 ng/L with a correlation coefficient of 0.994 96,the detection limit(LOD) was 72.7 ng/L.Actual water samples(tap water,Tai Hu Lake water,Gan Zhou Long Nan well water,mineral water) were analyzed.The recoveries ranged from 90.6%to 112.2%with relative standard deviations(RSDs,n=10) of 7.1%-21.5%.The detection for a single sample could be completed within 2-3 min.Therefore,as a powerful complement to traditional ICP mass spectrometer,the fast MPT mass spectrometry dection of hazardous metals cadmium in water has certain advantages,and could be developed as a line analysis method for environmental water,tap water quality monitoring,etc.关键词：microwave plasma torch(MPT);plasma mass spectrometry;cadmium;water
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发布时间： - 摘要：A novel poly neutral red film modified carbon paste electrode(PNR/CPE) was prepared by chemical initiation-electrochemical polymerization.The electrochemical properties of the modified electrode were characterized by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS),the surface morphology of the ploy neutral red film was observed by scanning electron microscopy (SEM).Meanwhile,the membrane structure of PNR was tested and analyzed by ultraviolet visible absorption(UV-Vis) and infrared absorption spectrometry(IR).The result showed that the neutral red was modified successfully on the surface of carbon paste electrode,and the surface of PNR/CPE had a specific three dimensional structure,in which the electroccatalytic performance was improved with the increase of the electroactive sites of the surface.Under the optimal experimental conditions,the modified electrode was applied in the detection of herring sperm DNA(hsDNA).The result indicated that a pair of obvious redox peak appeared on the PNR/CPE,the peak currents and concentrations of hsDNA had a good linear relationship in the range of 1.0×10-6-8.0×10-5 mol/L with a detection limit of 1.0×10-7 mol/L.关键词：ploy neutral red;chemical initiation;carbon paste electrode;characterization;herring sperm DNA(hsDNA)
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发布时间： - 摘要：A method combined probabilistic principal components analysis(PPCA) with support vector machine(SVM) was presented for analyzing SELDI-TOF-MS data generated from clinical proteomic study.Using PPCA for feature extraction on 322 MS data set,225 MS data set were randomly selected as learning set for establish SVM model，and the remaining 97 data set were selected as a testing set for prediction and verification.Root mean square error,recognition rate and predictive rate were used to evaluate the model′s classification performance,respectively.To verify the PPCA-SVM model′s classification performance further,the proposed model with partial least squares (PLS) model and PCA-SVM model were compared.The results showed that the recognition rates for PLS,PCA-SVM and PPCA-SVM were 90.92%, 99.23%and 99.01%,respectively,the predictive rates for PLS,PCA-SVM and PPCA-SVM were 76.38%,84.63% and 90.41%,respetively.Experimental results showed that proposed PPCA-SVM model was an accurate and repeatable method for automatically detecting prostate cancer.The method provides a new approach for early diagnosis of prostate cancer in clinic.关键词：prostate cancer;probabilistic principal components analysis;support vector machines;SELDI-TOF-MS
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发布时间： - 摘要：A method of HPLC-MS/MS with internal standard for the determination of L-carnitine in dairy products was developed.After the sample was dissolved in 0.1 mol/L HCl solution and its protein was precipitated with acetonitrile,the object was separated with a HILIC chromatographic column,tested by HPLC-MS/MS with sheath flow electro-spray ionization under positive ion scanning and multiple reaction monitoring(MRM) mode,and quantified by the internal standard method.The average recoveries at three spiked levels were in the range of 85.2%-102.0% with RSDs(n=6) of 7.6%-14.3%.The limit of detection (LOD) was 50 μg/kg and the limit of quantitation(LOQ) was 200 μg/kg.The proposed method was applied in the analysis of several real samples of different origins from overseas,and 20 samples were screened for L-carnitine with content range of 68-165 mg/kg,of which only 1 sample did not match with the label.This method was rapid,simple and accurate,and was suitable for the determining of L-carnitine content in dairy products.关键词：HPLC-MS/MS;L-carnitine;dairy products;internal standard
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发布时间： - 摘要：A novel variable selection method based on stability competitive adaptive reweighted sampling was applied to work with support vector machines（SVM-SCARS） for selecting informative variables of near infrared spectroscopy to build more robust SVM model.This method computed the stability index of each variable from a statistical analysis of weight vectors of multiple SVMs trained on subsamples of the original data by multiple sampling.The stability index represents the influence of variable on SVM modeling and could be used to evaluate the importance of variable.The variable with higher stability index was treated as informative variable that has an important effect on predictive performance of the model.Through iterations,the important variables was selected gradually by using adaptive reweighted sampling technology.Then the selected variables in each iteration were stored into variable subset.The optimal variable subset was determined by assessing the correct classification rate of cross validation（CCRCV） of SVM models based on all variable subsets.The SVM-SCARS algorithm combined with near-infrared diffusion reflectance spectrum technology were applied to construct wood identification model for four kinds of eucalyptus and two kinds of acacia.Experimental results showed that the SVM-SCARS model has a superior performance for identifying different wood species,in comparison to the full spectrum model and the support vector machine recursive feature elimination（SVM-RFE） model,both in terms of prediction ability and selected variables size.As a result,fifteen variables were selected by SVM-SCARS method to construct identification model with the correct classification rate of 97.9%.This study demonstrates that SVM-SCARS could effectively extract important characteristic variables from near infrared spectrum to improve the robustness and applicability of NIR online detection model for wood property analysis.关键词：near infrared spectroscopy;support vector machines;variable selection;wood species identification;pulp and paper
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发布时间： - 摘要：It was found that acetone has a cataluminescence (CL) phenomenon on the surface of ZnO/WO3 nanometerials.The luminescence characteristics and effect of different parameters,such as wavelength,temperature and flow rate were discussed by a prepared CL detection system.Based on this,a sensor was designed to detect acetone in human breath of diabetes.Under the optimized conditions,the linear range of CL intensity versus concentration of acetone vapor was 0.025 9-5.18 mg/L,with a limit of detection of 0.013 mg/L.The carbon dioxide,ammonia and water vapor in the breath had no obvious interference to the detection except for the ethanol.This sensor was evaluated continuously for 60 h with 1.30 mg/L gaseous acetone,and the relative standard deviation was 36%for 26 determinations.The sensor showed a better life.关键词：cataluminescence;nanometerials;acetone;human breath;diabete
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发布时间： - 摘要：A high performance liquid chromatographic（HPLC） method was developed to detect the content of lauroyl glutamate in coconut oleoyl glutamate surfactant and its sodium salts.The sample was dissolved with methanol in vortex mixer，and separated on an Agilent TC-C18（250 mm×4.6 mm×5 μm） column using acetonitrile-0.002 mmol/L H2SO4 as mobile phase at a flow rate of 1.0 mL/min.The detection wavelength was set at 203 nm;The injection volume was 10 μL.Under the optimal conditions,the calibration curve was linear in the range of 0.050-2.0 mg/mL with a detection limit（S/N=3） of 0.015 mg/mL.The recoveries were between 92.0% and 101%.With the advantages of accurancy,rapidness and good reproducibility,this method is suitable for the determination of cocoyl glutamate acid in different quality of fatty acids,and provides an effective reference for the quality control of this surfactants.关键词：high performance liquid chromatography（HPLC）;cocoyl glutamate acid;lauroyl glutamate
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- 2029
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发布时间： - 摘要：A molecularly imprinted solid phase extraction coupled with high performance liquid chromatographic (HPLC) method was firstly developed for the determination of clenbuterol hydrochloride residues in pork liver.The chromatographic conditions were as follows:the column:ASB C18 column(250 mm × 4.60 mm,5 μm),mobile phase:methanol-water (45∶55,pH 3.0),UV detection wavelength:243 nm,sample volume:10 μL,flow rate:0.6 mL/min,column temperature:30 ℃.Molecularly imprinted solid phase extraction conditions were as follows:solvent of sample loading:double distilled water,flow rate of loading:0.6 mL/min;elution solvent:methanol solution containing 1%trifluoroacetic acid.Under the optimal conditions,the calibration curve was linear in the range of 0.432-4.32 μg/mL,with linear equation of y=30 358x-307.74(r=0.999 0).The spiked recoveries were in the range of 84.7%-92.0%,with RSDs of 1.5%-1.8%.The accurancy and precision of the method could satisfy the requiremennts for residuals analysis.关键词：molecularly imprinted solid phase extraction;high performance liquid chromatography(HPLC);pork liver;clenbuterol hydrochloride
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