最新刊期
卷 38 ， 期 1 ， 2019
- 摘要：A method was developed for the identification of chemical constituents in Bufei Yishen formula by UPLC-Q-Orbitrap MS with Mass Frontier analysis software.The sample was separated on a Phenomenex kinetex C18 column(100 mm×2.1 mm,2.6 μm) by gradient elution with 1‰ formic acid-acetonitrile as mobile phase at a flow rate of 0.2 mL·min-1,a column temperature of 25 ℃ and an injection volume of 5 μL.Total of 242 chemical components in Bufei Yishen formula were confirmed by using Mass Frontier 60 workstation to match the collected fragment ions,combined with the literature report,in which 205 chemical components were confirmed in positive ion mode,including 10 from Ginseng Radix Rhizoma,17 from Astragali Radix,28 from Paeoniae Rubra Radix,9 from Fritillariae Thunbergii Bulbus,63 from Perillae Fructus,9 from Citri Reticulatae Pericarpium,8 from Ardisiae Japonicae Herba,7 from Corni Fructus,26 from Schisandrae Chinensis Fructus and 28 from Epimedii Herba.While 37 chemical components were confirmed in negative ion mode,ie23 from Ginseng Radix Rhizoma and 14 from Astragali Radix.The proposed method is comprehensive and rapid in the identification of chemical components in Bufei Yishen formula,which provides the basic data to reveal its pharmacodynamics substances.关键词：Bufei Yishen formula;UPLC-Q-Orbitrap MS;chemical constituents
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发布时间： - 摘要：In this paper,Fourier transform infrared spectroscopy(FTIR),attenuated total reflection Fourier transform infrared spectroscopy(ATR-FTIR) and ultraviolet(UV) spectra of the samples from six different areas in Yunnan and Guizhou provinces were collected,and the ATR-FTIR data were processed by ATR calibration.The models for single spectra and low level data fusion were established using different pretreatments including first derivatives(FD),second derivatives(SD) and standard normal variables(SNV) combined with partial least squares discriminant analysis(PLS-DA) and support vector machine(SVM).Results showed that the corrected ATR-FTIR(ATR-FTIR-A) spectral information was in agreement with the FTIR spectra.Additionally,second derivative processing could improve the UV resolution.ATR-FTIR-A and ATR-FTIR-A-UV low level data fusion models had the highest accurate rate(100.00%) and the best parameter values,which were established to identify Ppolyphylla from different regions by PLS-DA and SVM,respectively.Therefore,ATR-FTIR-A,with the simple and nondestructive characteristic in sample pretreatment,had a better performance than FTIR in identification of Ppolyphylla of different geographical origins .It was accurate in practical production and application.However,ATR-FTIR-A-UV had a better performance than PLS-DA or SVM with only one kind of spectra.关键词：Paris polyphylla Smith var.yunnanensis;attenuated total reflection Fourier transform infrared spectroscopy;partial least squares discriminant analysis;support vector machine;identification of geographical origin
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发布时间： - 摘要：A comprehensive analytical method was established for the rapid screening of 80 kinds of antibiotics and hormones in raw milk by ultra performance liquid chromatography-quadrupole time of flight mass spectrometry(UHPLC-QTOF MS)The milk samples were extracted with acetonitrile containing 1% acetic acid.The extracts were cleaned up through QuEChERS(Quick,Easy,Cheap,Effective,Rugged and Safe) method.80 target compounds were separated on an Agilent ZORBAX SB C18 column(3.0 mm×100 mm，1.8 μm) by gradient elution using acetonitrile-01% formic acid as mobile phases,and detected by MS under Dual AJS ESI+ mode.The analytes were quantified by the matrix-matched calibration standards.As a result,the calibration curves of 80 target compounds were linear in the certain concentration with their correlation coefficients not less than 0990 0.The limits of quantitation (LOQ,S/N=10) for the compounds in milk were in the range of 5-100 μg/kg.The average recoveries for 23 drugs in milk at LOQ spiked levels ranged from 50.2% to 59.7% with their relative standard deviations(RSDs) of 1.1%-13.0%,while those for the other 57 drugs ranged from 61.7% to 119% with their RSDs of 0.3%-19.0%.The screening and confirmation on the analytes were performed by using precision mass,retention time,isotopic abundance and two stage ion mass spectra.The method could be applied in the high throughput screening and identification of antibiotics and hormones in raw milk due to its characteristics of rapidness,simplicity,accuracy and sensitivity.关键词：ultra performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-QTOF MS);raw milk;antibiotics;hormones;rapid screening
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发布时间： - 摘要：A control system for triple quadrupole mass spectrometry(TQMS) was developed using LabVIEW software based on the NI development platform as it was widely used as an analysis and quantification tool for small molecules.The system hardware consisted of a PXIe board and some auxiliary circuits,which could realize the functions of air control,vacuum control,temperature control and scanning circuit control.The accuracy for gas flow control was 0.1%,the vacuum system pressure was 10-3 Pa,and the range and accuracy for temperature control were 0-850 ℃ and ±0.5 ℃,respectively.The control system was used for the determination of a cyclosporine A(CsA) standard sample,and a mass spectrum for the CsA sample was obtained.The half width for the ion peak with a mass number of 1 202.8 Da was 0.44 amu.Results showed that the control system,with good versatility,scalability and maintainability,could meet the requirements of the instrument by using object-oriented programming design,separating hardware from software to reduce the dependence of the software on the hardware.关键词：triple quadrupole;mass spectrometry;LabVIEW;control system
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发布时间： - 摘要：A novel model transfer method based on least angle regression(LAR) combined with simple linear regression direct standardization(SLRDS) was proposed to solve the problem of poor generality in model analysis of near infrared spectroscopy technology.In this method,the near infrared spectral data of the samples were preprocessed by wavelet transform,then the wavelength points for the spectral characteristic of the pre processed samples were screened by LAR.Finally,the selected wavelengths of the samples were corrected by SLRDS.Near infrared spectroscopy data for gasoline and drug samples were used to verify the performance of LAR-SLRDS.The spectral differences for the gasoline datasets C7,C8,C9 and C10 were 0.002 8,0.002 7,0.002 6 and 0.002 7,and the prediction standard deviations were 0.410 6,0.849 2,1.034 9 and 1.215 8,respectively.The spectral differences in activity,hardness and weight components of the drug datasets were 0.030 0,0.031 8 and 0.033 6,and the predicted standard deviations were 1.933 8,0.440 2 and 2.130 9,respectively.The experimental results showed that the LAR-SLRDS algorithm could not only eliminate the difference between the main and instrument spectra,but also improve the accuracy and stability of the PLS quantitative model.关键词：near infrared spectroscopy;model transfer;least angle regression;simple linear regression direct standardization
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发布时间： - 摘要：A method of high performance liquid chromatography(HPLC) with magnetic solid phase extraction(MSPE) was developed for the determination of four benzoylurea pesticides,ie.forchlorfenuron,penfluron,hexaflumuron and lufenuron in irrigation water.A magnetic metal organic framework sorbent(Fe3O4-NH2@MIL-101) was fabricated via solvothermal method.The composition and morpholgy of the composite were characterized by scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy(FT-IR) and X ray diffraction（XRD) analysis.Meanwhile,the magnetic intensity of the material was detected with a vibrating sample magnetometer.The determination of four analytes was performed by HPLC with the synthesized composite as MSPE adsorbent.The adsorption and elution factors，including adsorbent amount,adsorption time,pH value,elution time and elution volume,were investigated.Under the optimum conditions,the calibration curves for four benzoylurea pesticides showed good linear relationships in the range of 0.010-3.0 mg/L with correlation coefficients(r) higher than 0.999 5.The detection limits and the quantitation limits were in the ranges of 0.03-0.09 μg/L and 0.10-0.30 μg/L,respectively.The recoveries at three spiked levels ranged from 81.7% to 95.4% with RSD less than 10%.With a simple pretreatment process and an extraction time within 15 min,the method could be applied in the analysis on trace residues of benzoylurea pesticides in irrigation water.关键词：Fe3O4-NH2@MIL-101;magnetic solid phase extraction(MSPE);benzoylurea pesticides;irrigation water
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发布时间： - 摘要：An “off-on”type fluorescent probe with zinc doped carbon quantum dots(Zn-CQDs) was established for the selective and sensitive detection of glutathione(GSH).A stable and water soluble Zn-CQDs with high fluorescence quantum yield were prepared by one step hydrothermal method using citric acid,ethylenediamine and zinc acetate as precursors.The structures and optical properties of the Zn-CQDs were characterized by transmission electron microscopy(TEM),X ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),ultraviolet-visible absorption spectroscopy(UV-Vis) and fluorescence spectroscopy.Results showed that the fluorescence of Zn-CQDs was quenched by Cu2+,the fluorescence signal of the system was in the “off” state,while the fluorescence of Zn-CQDs-Cu2+ system was recovered because of the presence of reduced glutathione(GSH),and the fluorescence signal of the system was in the “on” state.The effects of pH value and reaction time on the fluorescence recovery system were investigated.The effects of small organic molecules and ions in fruits and vegetables on the fluorescence intensity of Zn-CQDs-Cu2+ system were also investigated.Under the optimal conditions,the fluorescence recovery rate of Zn-CQDs was linearly correlated with the concentration of GSH in the range of 0.05-80 μmol/L with the detection limit of 63 nmol/L.The probe was applied in the detection of GSH in fruits and vegetables with the recoveries of 98.6%-101% and the relative standard deviations(RSD) of 1.8%-3.1%,and the results were satisfactory.关键词：zinc doped carbon quantum dots;copper ions;fluorescence quenching-recovery;glutathione
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发布时间： - 摘要：A liquid chromatography-tandem mass spectrometric(LC-MS/MS) method was developed for the determination of brilliant green,methylene blue and their metabolites in aquatic products.The samples were extracted with ammonium acetate buffer solution and acetonitrile,followed by extraction with dichloromethane,then purified on a PRS solid phase extraction column.The eluent was concentrated by nitrogen blowing,diluted to a certain volume and determined.The targets were separated on a CAPCELL PAK C18 column with 2 mmol/L aqueous ammonium acetate containing 01% formic acid,acetonitrile and methanol as mobile phases.The determination of the analytes was performed by LC-MS/MS in selected reaction monitoring(SRM) mode,and the external standard method was used for quantitation.There existed good linear relationships for the analytes in the range of 10-100.0 μg/L with their correlation coefficients(r2) larger than 0.999.The limits of detection(LOD,S/N≥3) and quantitation(LOQ,S/N≥10) were 1.0 μg/kg and 2.0 μg/kg,respectively.The average recoveries at three spiked levels of 1.0,5.0 and 10.0 μg/kg were in the range of 70.3%-92.1% with their relative standard deviations(RSDs,n=6) of 23%-13%.The method has high sensitivity and could be used in the effective detection on residues of brilliant green,methylene blue and their metabolites in aquatic products.关键词：brilliant green;methylene blue;metabolites;aquatic products;liquid chromatography-tandem mass spectrometry(LC-MS/MS)
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发布时间： - 摘要：Based on C8 modified macroporous silica,a coated cellulose tri(4 methylbenzoate)(CTMB) chiral stationary phases(CSPs) were prepared.Influences of coating solvent and additive on the enantioselectivity of CSP were investigated.Several CSPs were prepared by coating CTMB in chloroform and dichloromethane,with N,N’ dimethylformamide(DMF),phenol,nitrobenzene,methyl benzoate and acetophenone as additives,respectively.The enantioselectivities of CSPs were evaluated by using 7 structurally different enantiomers.It was found that column efficiency,retention ability and enantioselectivity of CSPs were affected by the type and amount of additive.The addition of the same amount of methyl benzoate with CTMB would provide the CSPs with better properties,which exhibit a good enantioseparation ability for racemic simendan intermediate and ketorolac,and possess an application potential in industrial preparation and separation.关键词：coating;solvent;cellulose tri(4 methylbenzoate);chiral stationary phases;enantiomers resolution
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发布时间： - 摘要：A simple and sensitive method was developed for the determination of ethephon residues in cotton seed,cotton leaf and soil by solid phase extraction/ultrahigh performance liquid chromatography-tandem mass spectrometry(SPE/UPLC-MS/MS).The samples were extracted with methanol-01% formic acid,purified with an Oasis MAX column,and separated on a Cortecs Hilic column,finally analyzed in multiple reaction monitoring(MRM) mode via negative electrospray ionization(ESI-).Under the optimum condition,the calibration curves for the analyte were linear in the range of 0.02-1.94 mg/L,with correlation coefficients(r2) not less than 0.996 3.The limits of detection and quantitation for ethephon were 0.01 and 0.02 mg/kg,respectively.At spiked levels of 0.02,0.194 and 3.88 mg/kg,the recoveries for ethephon in three matrices were in the range of 78.3%-95.1% with relative standard deviations(RSDs) of 1.9%-5.2%.With the advantages of simplicity,high sensitivity,and good repeatability,the method could satisfy the requirements for determination of ethephon in cotton seed,cotton leaf and soil.关键词：ethephon;ultrahigh performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS);residues;cotton seed;cotton leaf;soil
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发布时间： - 摘要：A method was developed for the simultaneous determination of 19 chlorinated phenols in textiles by liquid chromatography-mass spectrometry(LC-MS).The textile samples were extracted with methanol in ultrasonic bath,then evaporated and set to volume.The target compounds were analyzed by LC-MS and quantified by the external method.The calibration curves for 19 chlorinated phenols were linear(r>0.999 90) in the concentration range of 0.05-5.0 mg/L.The average recoveries were in the range of 80.3%-104% with their relative standard deviations(RSD,n=6) of 4.0%-9.8%.The quantitation limits were 0.05 mg/kg.The method was sensitive,simple,efficient and accurate,and could meet the requirements for detection of chlorinated phenols in textile products.关键词：textiles;chlorinated phenols;simultaneous determination;liquid chromatography-mass spectrometry(LC-MS)
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发布时间： - 摘要：Aqueous biphasic system(ABS) based on the surfactant(triton x-100,Tr) and cholinium ionic liquids were developed for the extraction of triazine herbicides in honey samples.The influences of phase compositions and temperature on the formation of ABS were investigated.The biphasic region of ABS decreased with the increase of carbon chains of the anions in ionic liquids,but made no distinct difference with the increase of temperature.The partitioning behaviors of the selected herbicides were investigated using the Tr-choline acetate(［Ch］［Ac］)ABS.Results showed that the analytes were mainly concentrated in the surfactant-rich phase.The partition coefficients of the herbicides decreased with the increase of Tr mass fractions,while increased with the increase of ［Ch］［Ac］concentrations,which indicated that the salting-out ability of the ionic liquid played an important role in the system formation.Under the optimized conditions,there were good linear relationships for the selected herbicides over the concentration range of 0.1-20.0 mg/L with correlation coefficients(r2) not less than 0.992.The limits of quantitation for the analytes ranged from 0.005 mg/kg to 0.02 mg/kg,and the average recoveries were between 75.0% and 114% with RSDs of 5.2%-76%.The proposed method is suitable for the determination of the target herbicides in honey samples.关键词：aqueous biphasic system;cholinium ionic liquid;partition coefficient;triazine herbicide;high performance liquid chromatography(HPLC);honey
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发布时间： - 摘要：A method of gas chromatography-mass spectrometry(GC-MS) with steam distillation(SD) and supercritical CO2 extraction(SC-CO2) was developed for the analysis of components of essential oil in leaves of Zanthoxylum piperitum ‘Odorum’.The samples were extracted by SD and SC-CO2,respectively,then analyzed by GC-MS. The quality of extracts was distinguished by determining the scavenging ability and reducibility for free radical DPPH·.A total of 34 components,extracted by both SD and SC-CO2,were mainly lipids and alkenes.However,the types of components obtained by the two methods were significantly different.The SD extracted components,contained relatively high contents of ethyl benzene(43.15%),methyl cinnamate (30.33%),α-caryophyllene(1.81%) and α-myrcene(8.41%).In contrast,the SC-CO2 method mainly yielded methyl cinnamate (73.91%),limonene(11.13%) and α-caryophyllene(4.12%).As the scavenging ability for DPPH· was concerned,the essential oils extracted by SC-CO2 reached the butylated hydroxytoluene(BHT) inhibition rate of 97.27% at the concentration of 8 mg/mL,with an IC50 of 3.173 3.At 20 mg/mL,their reducibility reached to 34.86% of that of vitamin C(Vc).In contrast,the SD extracted essential oils only had a BHT inhibition rate of 14.27% at 20 mg/mL,and 5.98% of Vc reducibility.Therefore,the differential components between the two extraction methods were mainly those reductive and antioxidative substances such as phenols and terpenes.In conclusion,the essential oils extracted from leaves of Zanthoxylum piperitum by SC-CO2 contained more insect repelling and antimicrobial agents,and its extraction effects were superior to those of SD method.关键词：steam distillation(SD);supercritical CO2 extraction(SC-CO2);Zanthoxylum piperitum;essential oil;GC-MS
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发布时间： - 摘要：An ultrahigh performance liquid chromatographic(UPLC) method was developed for the determination of paeonol(Pae),thymol(Thy),honokiol(Hon),magnolol(Mag) and glycyrrhetinic acid(Gly) in toothpaste.The sample was ultrasonically extracted with 90% methanol.After centrifugation and filtration,the supernatant was separated on a Waters ACQUITY UPLCHSS C18 column(2.1 mm×100 mm,1.8 μm) by gradient elution at a flow rate of 0.3 mL/min,using acetonitrile and 0.1% formic acid(pH 2.8) as mobile phases.The ultraviolet detection wavelength was set at 275 nm and 250 nm,respectively.Results indicated that the five botanic active constituents had good linear relationships in the range of 2-100 mg/L with their correlation coefficients(r) more than 0.999.The limits of detection and quantitation were in the ranges of 0.2-1.0 mg/kg and 0.8-3.5 mg/kg,respectively.The average recoveries at four spiked levels ranged from 90.5% to 99.4% with their relative standard deviations(RSDs) of 0.7%-5.1%.With the characteristics of rapidness,good repeatability,accuracy and sensitivity,the method was applied in the analysis on botanic active constituents in real toothpaste samples.关键词：ultrahigh performance liquid chromatography(UPLC);botanic active constituents;toothpaste
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发布时间： - 摘要：A high performance liquid chromatography with indirect ultraviolet detection was developed for the determination of pyrrolidinium ionic liquid cations by using reversed phase C18 column and UV detector.As an additive of mobile phase,imidazolium ionic liquid is not only a background ultraviolet absorption reagent,but also an effective component for improving the separation of the analytes.The addition of the ion pairing reagent sodium heptanesulfonate to the mobile phase could better improve the separation of cations in the pyrrolidinium ionic liquid.Under the optimal chromatographic conditions,the three pyrrolidinium ionic liquid cations(［MEPy］+,［MPPy］+ and ［MBPy］+) could be effectively separated and detected within 13 min.The linear ranges for ［MEPy］+,［MPPy］+ and ［MBPy］+ were 0.6-100 mg/L,1.3-230 mg/L and 3.6-250 mg/L,respectively,with their correlation coefficients(r) more than 0.999.The detection limits for three analytes were 0.2,0.4,1.1 mg/L,respectively.The method was applied in the detection of homologue pyrrolidinium ionic liquid samples synthesized in laboratory with spiked recoveries of 92.2%-96.7%.The method is accurate and reliable,and is suitable for the separation and detection of pyrrolidinium ionic liquid cations.关键词：high performance liquid chromatography;indirect ultraviolet detection;pyrrrolidinium cations;ion pair reagents;imidazolium ionic liquids
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发布时间： - 摘要：An outstanding UV shielding agent based on graphene oxide modified ZnO/CeO2 nanocomposites was prepared by sol-gel method using zinc nitrate hexahydrate，ceric nitrate hexahydrate and graphene oxide（GO） as raw materials.The structure，composition and morphology of the as prepared sample were characterized by X ray diffraction（XRD），scanning electron microscopy（SEM），Fourier transform infrared spectroscopy（FT-IR） and ultraviolet and?visible spectrophotometry（UV Vis）.The influences of molar ratio of cerium oxide to zinc oxide，mass of graphene oxide，amount of shielding agent loaded and pH value on the UV shielding performance of the GO/ZnO/CeO2 nanocomposites were investigated.The average sizes for GO，CeO2 and ZnO in the graphene oxide modified ZnO/CeO2 nanocomposites were 8.3，15.4 and 37.5 nm，respectively.The optimum conditions were as follows: pH value: 6.0，molar ratio of cerium oxide to zinc oxide: 4 ∶ 1，mass of graphene oxide: 2.0 g，amount of shielding agent loaded: 0.06 g/L.Under the optimal conditions，the sequence for UV shielding performances of the agents were as follows: graphene oxide modified ZnO/CeO2 nanocomposites>GO>ZnO/CeO2 nanocomposites>CeO2>ZnO.关键词：UV shielding performance;ZnO;CeO2;graphene oxide(GO);nanocomposite
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发布时间： - 摘要：Pyrethroids molecular imprinted polymer were synthesized by precipitation polymerization,using phenyl ether biphenyl,a structural analogue of pyrethroids as the pseudo template.The optimal conditions for synthesis were as follows:the ratio of template molecule(phenyl ether biphenyl),functional monomer(4 vinylpyidine) and cross linker(ethylene dimethacrylate) was 1∶6∶20,the reaction temperature was 70 ℃and the amount of thermal polymerization initiator was 1%.The synthesized molecularly imprinted polymers were characterized by scanning electron microscopy and their adsorption performances were determined.The maximum adsorption capacity of the polymers toward 60 μg·mL-1 diphenyl ether biphenyl eutectic was 6 041 μg·g-1.Results of the adsorption rate showed that the polymers could reach an adsorption equilibrium after 7 h.The absorption amounts of the synthesized polymers toward chlorpyrifos,bifenthrin,fenpropathrin,permethrin,cypermethrin and fenvalerate were 259，316，311，271，305 and 298 μg·g-1,while those of the non imprinted polymers were 169，188，181，183，151 and 142 μg·g-1,respectively.The selectivity of the imprinted polymers is higher than that of the non imprinted polymers.关键词：precipitation;fragment imprinting;pyrethroids;solid phase extraction
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发布时间： - 摘要：An electrochemiluminescence sensor was fabricated for the determination of benzhexol hydrochloride based on a pyrolytic graphite electrode modified with multi walled carbon nanotube(MWNT)/nano Ag/Silica sol/professional video assistant(PVA)/Ru(bpy)2+3.In light of the perfect conductivity of MWNT and the electrocatalysis of nano-Ag,silicon sol and polyvinyl alcohol were used as film forming agents to fix MWNT,nano-Ag and Ru(bpy)2+3 on the pyrolytic graphite electrode(PGE) by sol gel method,and benzhexol hydrochloride was detected on the MWNT/nano-Ag/Silica sol/PVA/Ru(bpy)2+3-PGE by electrogenerated chemiluminescence(ECL) according to the sensitization of benzhexol hydrochloride to Ru(bpy)2+3.Results indicated that there was a good linear relationship for the ECL intensity of benzhexol hydrochloride in the range of 4.36×10-7-1.09×10-4 mol·L-1 with a correlation coefficient(r2) of 0.997 3 and a linear equation of IECL=146.98×105 c+502.03The limits of detection were 2.06×10-8 mol/L(S/N=3).The recoveries for benzhexol hydrochloride at five spiked levels were in the range of 97.7%-104% with the RSDs of 2.4%.The method was applied in the detection of benzhexol hydrochloride drugs with good sensitivity and stability.关键词：MWNT;nano-Ag;pyrolytic graphite electrode;electrogenerated chemiluminescence;benzhexol hydrochloride
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发布时间： - 摘要：A novel electrochemiluminescence(ECL) method was developed for the sensitive detection of methimazole based on the fact that in the alkaline medium,the weak ECL signal of luminol could be significantly enhanced by a little amount of methimazole on the surface of graphene modified glass carbon electrode.The effects of reaction medium,graphene dosage,luminol concentration and electrochemical scanning rates on ECL signal of the selected system were investigated.Results showed that under the optimal contions of 8.0 μL of graphene amount,0.01 mol·L-1 of sodium hydroxide,0.7 μmol·L-1 of luminol and 100 mV/s of electrochemical scaning rate,the increased ECL intensity for methimazole was linear in the concentration range of 6.0×10-8-1.0×10-5 mol·L-1 with a detection limit of 2.0×10-8 mol·L-1 and a relative standard deviation(RSD) of 3.5%(c=0.5 μmol·L-1,n=11).The proposed method could be applied in the clinical analysis of methimazole tablets with satisfactory results.关键词：graphene;modified glass carbon electrode;electrochemiluminescence;luminol;methimazole
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发布时间： - 摘要：Food flavor is an important indicator evaluating quality characteristics.Usually,food flavor substances were analyzed by 1D-GC or GC-MS method.But sometimes,it is hard to separate some constituents due to the complexity of components of food flavor and matrices.The second separation of complicated flavor components in food could be realized by comprehensive two dimensional gas chromatography(GC×GC) with better separation ability and analysis speed via the orthogonal combination of two independent columns of different mechanisms.The applications of GC×GC in the analysis of flavor components in edible agricultural products without secondary processing,such as fruits,vegetables and meat,as well as the secondary processed foods including dairy products,drinks and condiments were reviewed.The technical features for GC×GC were also exhibited in this paper, and references were provided for the analysis of food flavor.关键词：comprehensive two dimensional gas chromatography;food flavor;chemical component;review
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