最新刊期
卷 36 ， 期 1 ， 2017
- 摘要：A high-performance liquid chromatograph-mass spectrometric(LC-MS/MS) method was proposed for the determination of thirty chemical compositions,which were illegally mixed into the antiobesity traditional Chinese medicine and health products.The conditions of extraction and mass parameters were optimized.The drugs were extracted with methonal in ultrasonic condition,separated on a C18 chromatographic column using a mixture of acetonitrile and water(containing 10mmol/L ammonium formate,0.1% formic acid，10% methanol) as mobile phase.The detection of analytes was performed by positive-ion and negative-ion electrospray ionization mass spectrometry(ESI-MS) under multiple reaction monitoring(MRM) mode.The method was proved to be able of covering large area,simple,rapid,accurate and reliable.It was used in screening and examination of illegally added chemicals in Chinese traditional medicine and health food.关键词：antiobesity chemical drugs;liquid chromatography-tandem mass spectrometry(LC-MS/MS);Chinese traditional medicine and health food
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发布时间： - 摘要：MS/MS fragmentation patterns of five flavone di-C-glycoside standards from Viola yedoensis were studied by ultrahigh performance liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry（UPLC-ESI-QTOF-MS/MS） in the negative ion mode.The fragmentation pathways of C-6 and C-8 sugars in these flavone di-C-glycosides were consistent with those reported earlier.The results of our study also suggested that the configurations of sugars at C-8 obviously influenced the fragmentation behaviors.The fragmentation behaviors of these flavone di-C-glycoside standards were successfully used to characterize flavone C-glycosides in V.yedoensis.Total of 21 flavone di-C-glycosides along with 4 flavonol O-glycosides were identified or tentatively identified on the base of their MS/MS data，accurate molecular weights，or by comparing with reference standards.The UPLC-ESI-QTOF-MS/MS method is rapid，sensitive and accurate,and could be used for the characterization of flavone C-glycosides in traditional Chinese medicines.关键词：Viola yedoensis;flavone C-glycoside;quadrupole time of flight-mass spectrometry（QTOF-MS）;liquid chromatography-mass spectrometry（LC-MS）
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发布时间： - 摘要：In this work，the molecularly imprinted polymers（MIPs） for chloramphenicol（CAP）（CAP-MIPs） were prepared by ionic liquids assistance using 2-vinylpyridine as functional monomer，ethylene glycol dimethacrylate（EGDMA） as the cross-linker and 2,2′-azobisisobutyronitrile（AIBN） as the initiator in the mixture of tetrahydrofuran and ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate（［BMIm］BF4） as the porogenic solvent.The effects of functional monomer，progenic solvent on the binding capacity of MIPs were optimized.The MIPs possessed a high capacity and a favorable selectivity for CAP in the preparation of MIPs using 2-vinylpyridine as functional monomer and ionic liquid（［BMIm］BF4）（1∶1，by volume） as polymeric solvent.The imprinting factor of CAP-MIPs reached to 2.6.The reusability of CAP-MIPs without any deterioration in capacity was demonstrated for five adsorption-desorption cycles.The developed method was applied in the enrichment and determination of CAP in spiked egg samples using CAP-MIPs as the adsorbent,with CAP recoveries of 62.3%-81.1%.关键词：chloramphenicol;molecularly imprinted polymers(MIPs);ionic liquids;egg;enrichment
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发布时间： - 摘要：A rapid method for the determination of extractables in pharmaceutical packaging materials was developed by ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry(UPLC-QTOF-MS) based on UNIFI software and a polymer additive library.The samples were extracted with chloroform,and then the extractables were separated on a CORTECS C18(2.1mm×100mm,1.6μm) column using a binary solvent system composed of methanol and 0.1% formic acid water solution. Screening and quantitative analysis were accomplished by UPLC-QTOF-MS under positive electrospray ion mode.The results showed that four extractables were detected in buffered saline(25℃,60 days).Diisodecyl phthalate(DIDP) was identified by library searching and quantitated by external standard method with a concentration of 1.98 μg/L.The other three extractables were inferred and identified by accurate mass and MSE spectra match,and they were quantitated with dicyclohexyl phthalate(DCHP).The total content of the three compounds was 10.80μg/L.The recovery analysis was carried out to evaluate the method with DIDP.The results indicated that the recoveries of DIDP ranged from 90.1% to 97.1% with relative standard deviation(RSD) no more than 3.7%(n=6) at three spiked concentration levels(5,10,20μg/L).The method was rapid, accurate and sensitive,and was suitable for the safety investigation on pharmaceutical packaging materials.关键词：nonvolatile extractables;pharmaceutical packaging material;ultra performance liquid chromatography tandem quadrupole-time-of-flight mass spectrometry(UPLC-QTOF-MS);library searching
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发布时间： - 摘要：A self-assembly pipette tip solid-phase extraction(PTSPE)/high-resolution benchtop Q Exactive mass spectrometric(HRMS) method for the analysis of 15 acidic pesticides in fruit was established.The samples were first extracted with 1% formic acid in acetonitrile,and then the extracts were cleaned up using PTSPE procedure with the adsorbent of PEP and HILIC.The chromatographic analysis was performed on a T3 column.And the qualitative and quantitative analyses were performed under tSIM/ddMS2 mode by high resolution mass spectrometry.The internal standard calibration was used for quantification,and the method showed a good linearity(r2＞0.99) in a certain concentration range for the 15 acidic pesticides.The limits of quantitation(LOQ) were between 0.2μg/kg and 10μg/kg.The recoveries of the analytes in apples,cherry tomatoes and strawberries samples at spiked levels of LOQ,10μg/kg and 100μg/kg ranged from 73.5% to 115.9%,with relative standard deviations(RSDs) of 1.0%-8.3%.The results showed that the method was sensitive and accurate,and was suitable for the analysis of acidic pesticides in fruit．关键词：pipette tip solid-phase extraction(PTSPE);ultra high performance liquid chromatography-high resolution mass spectrometry(UPLC-HRMS);fruit;acidic pesticides
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发布时间： - 摘要：An analytical method for the rapid analysis of edible vegetable oils was developed by ambient flame ionization mass spectrometry(AFI-MS).The AFI-MS was used to analyze four edible vegetable oils,including olive oil,sesame oil，peanut oil and sunflower oil.26 kinds of triglycerides and 11 kinds of dialycerides in olive oil,peanut oil,sunflower oil,sesame oil were detected by the AFI-MS.In view of the differences of MS profiles of edible vegetable oils(olive oil,sesame oil，peanut oil and sunflower oil),the relative abundances of triglycerides in edible vegetable oils were obtained.The differences of relative abundances were capable of preliminary identification of four edible vegetable oils.The experimental results demonstrated the feasibility and convenience for fast analysis of edible vegetable oils by the AFI-MS.The results showed that the simple and convenient AFI-method is potential for fast analysis of edible vegetable oils.关键词：ambient flame ionization mass spectrometry;edible vegetable oils;dialyceride;triglyceride
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发布时间： - 摘要：A method of ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) was developed for the determination of cyenopyrafen residues in fruits and vegetables.The analytes were extracted from the samples using acetonitrile,and purified by dispersion solid phase extration using C18 and PSA as solid phase,then analyzed by UPLC-MS/MS.The matrix-induced weakening effect was observed in the analysis of cyenopyrafen by UPLC-MS/MS in serval samples including of cucumber,apple and onion.The interference of matrix was reduced by the matrix-matched calibration standards curve.The linear ranges of cyenopyrafen in different matrices ranged from 0.05μg/L to 10μg/L with correlation coefficients not less than 0.9996.The recoveries of cyenopyrafen in cucumber,grape,apple and scallion samples at spiked levels of 0.00005-2mg/kg were in the range of 81.1%-99.3%,with relative standard deviations(RSDs) of 4.7%-9.3%.The limit of quantitation was 0.043μg/kg and the limit of detection was 0.013μg/kg.关键词：ultra performance liquid chromatography-tandam mass spectrometry(UPLC-MS/MS);vegetables;fruits;cyenopyrafen;residues
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发布时间： - 摘要：A rapid method was developed for the determination of HT-2 toxin,T-2 toxin,fumonisin B1,fumonisin B2,zearalenone,ochratoxin A,deoxynivalenol and aflatoxins B1 in rice.Three dispersive solid phase extraction sample preparation methods,including QuEChERS method,EMR-lipid method and DisQuE method,were compared for the determination of 8 mycotoxins in rice.The recoveries of the three extraction methods for the toxins were studied.The method of after-extraction addition was used to evaluate the matrix effects for mycotoxins in rice by liquid chromatography-tandem mass spectrometry(LC-MS/MS).As a result,the QuEChERS method was not suitable for the analysis of fumonisin B1,fumonisin B2 and ochratoxin A.The EMR-lipid methods could not overcome the matrix effects of zearalenone and ochratoxin A in rice.In this study,mycotoxins were extracted by DisQuE method,and analysed by LC-MS/MS under the optimized condition with monitoring 16 pairs of MS/MS transitions of precursor ions(two for each mycotoxin) in one single run.Recoveries at three fortified levels in rice ranged from 70.0% to 124.1% with relative standard deviations of 0.9%-16.9%.The limits of detection(S/N≥3) were in the range of 1.2-60.0 μg/kg.The method was proved to be highly efficient,robust and sensitive,and was suitable for the simultaneous analysis of mycotoxins in rice.关键词：QuEChERS method;EMR-lipid method;DisQuE method;liquid chromatography-tandem mass spectrometry(LC-MS/MS);mycotoxins;rice
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发布时间： - 摘要：A QuEChERS coupled with liquid chromatography-tandem mass spectrometric(LC-MS/MS) method was developed for the detection of 17 carbamate pesticides in five vegetables.The matrix effects in ginger,scallion,cucumber,carrot and cabbage,together with the influences of matrix type,matrix concentration and pesticide concentration on the matrix effects were discussed.The results showed that,the liner ranges of 17 pesticides in different vegetables ranged from 5 μg/L to 100 μg/L,and the recoveries ranged from 76.5% to 111.8% with relative standard deviations of 2.5%-8.2%.Different vegetables present different matrix effects for the responses of 17 pesticides in LC-MS/MS,mostly the matrix suppression effects,which were impacted by matrix type,matrix concentration and pesticide concentration.In addition,the matrix effects of thiodicarb and diethofencarb in carrot and thiodicarb in cucumber ranged from 0.8-1.1 despite of matrix concentrations and pesticide concentrations,suggesting the matrix effects of these circumstances advisably being ignored in routine testing.However,the matrix effects must be considered carefully during detection procedures of 17 carbamate pesticides in ginger,scallion,cucumber,carrot and cabbage.关键词：QuEChERS;matrix effects;liquid chromatography-tandem mass spectrometry;vegetables;carbamate;pesticides
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发布时间： - 摘要：A method using magnetic multi-walled carbon nanotubes(mMWCNTs) as the absorbent followed by ultra-performance liquid chromatography-tandem mass spectrometry was established for the determination of 44 veterinary drugs residues in honey.Analytes were extracted with Na2EDTA-Mcllvaine buffer solution(pH 4.0) before self-made mMWCNTs were added to absorb veterinary drugs.After extraction with mMWCNTs and followed by elution with 10% ammonia-methanol,target analytes were analyzed using multiple reaction monitoring(MRM) mode.The correlation coefficients of linear calibration curves were over 0.99 in the concentration range of 1-40 ng/mL.The recoveries of 44 analytes at three spiked concentrations ranged from 78.0% to 105.1%,with relative standard deviations(RSDs) of 1.2%-8.9%.The limits of detection(LODs,S/N≥3) were 0.2-2.0 μg/kg.With the advantages of simplicity,sensitivity and good precision, this method provides a new way for the determination of multi-veterinary drug residues in honey.关键词：magnetic multi-walled carbon nanotubes;sulfonamide;nitroimidazole;quinolone;honey
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发布时间： - 摘要：A gas chromatograpy-tandem mass spectrometric(GC-MS/MS) method for the determination of nineteen organophosphorus pesticides in vegetables was developed using dispersive solid-phase extraction(DSPE) and dispersive liquid-liquid micro-extraction(DLLME) as sample preparation methods.With dispersive solid-phase extraction,PSA and C18 were used as the sorbents,and acetonitrile as the eluted solvent.Some experimental parameters influencing the extraction efficiency,such as the types and volume of the dispersive solvents and extraction solvents were examined and optimized.Gamma-L-gulonic acid lactone(AP) used as a masking regent for compensation effect of matrix was evaluated.Under the optimum conditions,the recoveries of nineteen organophosphorus pesticides in pepper chili and shallot samples at fortified levels of 0.05,0.1,0.5 mg/kg ranged from 76.9%to 126.8%with relative standard deviations of 0.6%-7.3%.The limits of detection(S/N=3) were in the range of 0.10-0.50 μg/kg.With the advantages of quickness,low toxicity and high enrichment factors,the proposed method is applicable for the analysis of organophosphorus pesticides in vegetables.关键词：dispersive liquid-liquid micro-extraction;dispersive solid-phase extraction;gas chromatography-tandem mass spectrometry(GC-MS/MS);organophosphorus pesticides;vegetables
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发布时间： - 摘要：An ultra-performance liquid chromatography coupled with time-of-flight mass spectrometric(UPLC-QTOF-MS) method was developed for the analysis of the differences among chemical compositions in Polygoni Multifori Radix processed by different methods.The samples were extracted with methanol by ultrasonic at room temperature and centrifuged.The extracts were analyzed by UPLC-QTOF-MS.After peak matching,peak alignment and noise filtering of characteristic peak extraction,the obtained data were analyzed by principal component analysis(PCA) and partial least-squares discriminant analysis(PLS-DA).The results demonstrated that there were significant differences among the samples of Polygoni Multifori Radix with different processing methods.Accurate mass measurements and CID experiments as well as the software of database searching and literature component identification were applied to identify.The chemical compositions of Polygoni Multifori Radix by different processing methods were analyzed,and 33 constituents were identified.Among them,15 constituents were the common chemical composition presented in different changing laws.The research provided experimental data for revealing the laws of different processing methods on metabolites of Polygoni Multifori Radix.关键词：Polygoni Multifori Radix;ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry(UPLC-QTOF-MS);processing methods;the difference of chemical composition
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发布时间： - 摘要：By utilizing Support Vector Machine(SVM) technique to analyze full chromatographic data of Flash GC，a method was proposed to identify A brand and non-A brand cigarette.Moreover，it can identify cigarettes of different price class，including first，second and third class.Meanwhile，it can also distinguish different price class cigarettes in the same style.It can discriminate A brand cigarettes of Ⅰstyle，Ⅱstyle，Ⅲ style and Ⅴstyle，but Ⅳ style and Ⅴstyle can not be completely distinguished because they are too close.The satisfied predicted results were obtained due to the adoption of liner kernel function and full chromatographic data，because every cigarette sample has its characteristic fingerprint chromatography and full chromatographic data can capture the minute differences among samples.关键词：Flash GC electronic nose;support vector machine;price class;style
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发布时间： - 摘要：A novel method of hollow fiber liquid phase microextraction(HF-LPME) coupled with thin-layer chromatography was developed for the synchronous spectrofluorimetric determination of tryptamine in soy sauce.The optimum extraction was achieved by adjusting pH value of sample solution to 12.0,using 1-octanol as organic extraction solvent,and 0.1 mol/L HCl as the acceptor phase,and stirring the solution at 590 r/min for 60 min.After extraction,20 μL portion of accepter phase was applied for TLC separation,and the analyte spot was washed off with isopropanol.The quantification analysis of tryptamine was performed with synchronous fluorescence spectra at 350.4 nm.Under the optimum conditions,the calibration curve showed a good linearity in the range of 0.32-50 mg/L(r>0.978 0).The detection limit was 0.32 mg/L.The spiked recoveries from soy sauce samples were in the range of 87.5%- 107.7% with RSDs not more than 6.6%.The proposed method was simple,sensitive,green and accurate,and was suitable for the determination of tryptamine in soy sauce.关键词：hollow fiber three-phase liquid phase microextraction;thin-layer chromatography;tryptamine;soy sauce;fluorophotometry
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发布时间： - 摘要：A poly amino acid film was modified on the surface of glassy carbon electrode by electro polymerization,then the copper metal organic frameworks(MOFs) with excellent electrical conductivity and catalytic ability were self-assembled on the surface of the modified electrode via carboxyl coordination.The voltammetric behaviors of metronidazole(MNZ) on the modified electrode and its electrocatalytic properties were studied.Thus,a MNZ electrochemical sensor with preeminent sensitivity was established.The method had a good linearity in the range of 1.0-100.0 μmol/L with a detection limit of 0.23 μmol/L,and was also successfully applied in the detecttion of MNZ in the honey sample.关键词：Cu-MOFs;metronidazole(MNZ);modified electrode;electrocatalysis
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发布时间： - 摘要：A novel method for the simultaneous determination of 18 PAHs in river was established by solid-phase extraction coupled with ultra-high performance liquid chromatography(SPE/UPLC).The effects of solid phase,elution system and gradient elution were optimized.Under the optimal conditions,18 PAHs could be separated in 7 min.The calibration curves of 18 PAHs showed good linearity between peak area and concentration in the range of 0.05-50 mg/L,with correlation coefficients of 0.999 1-0.999 9.The detection limits were between 0.08 ng/L and 2.03 ng/L,with relative standard deviations(RSDs) of 0.5%-2.3%.The spiked recoveries were in the range of 74.5%-103.6%.It provided a reliable method for the study of PAHs in the Longyan section of Nine Longjiang River Basin.The method is simple,sensitive,accurate and efficient,and could significantly improve the analysis efficiency of trace PAHs in rivers.关键词：peanut shell activated carbon;solid phase extraction;polycyclic aromatic hydrocarbons;ultra high performance liquid chromatography
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发布时间： - 摘要：A model peptide,Tyr-Tyr-Tyr-Tyr（YYYY）,was synthesized by Fmoc solid-phase methods,purified and separated by reverse phase high performance liquid chromatography（RP-HPLC）,and characterized by ESI-MS analysis.The interaction of peptide with calf thymus DNA(ct-DNA) was investigated by UV-Vis absorption spectra,circular dichroism(CD) and fluorescence spectra.The results showed that,with the increase of peptide concentration,there were a hyperchromic effect on UV spectra,a remarkable fluorescence quenching and a red shift of CD.It is possible that Tyr-Tyr-Tyr-Tyr and Tyr might interact with ct-DNA via the groove binding mode.The interaction between Tyr-Tyr-Tyr-Tyr and ct-DNA,compared with that between Tyr and ct-DNA,is more stronger.关键词：Tyr-Tyr-Tyr-Tyr;ct-DNA;interaction;Fmoc solid-phase methods
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发布时间： - 摘要：A method of extraction of belsoline and eldeline in Delphinium anthriscifolium Hance was developed by pressurized microwave assisted extraction(PMAE).The single factor test and orthogonal test were used to optimize the experimental conditions.The optimum extraction conditions were as follows:particle size:100 mesh,ratio of solid to liquid:1∶60,microwave temperature:80 ℃,microwave power:560 W,microwave time:10 min.Under the optimal conditions,belsoline and eldeline were separated,and determined by HPLC using methanol-0.2% triethylamine(45∶55) as mobile phase.The linear ranges of belsoline and eldeline were in the ranges of 0.50-50.0 mg/L and 0.30 -30.0 mg/L,respectively.The recoveries of belsoline and eldeline were in the range of 98.3%-104.5%,and RSDs were 2.0% and 2.2%,respectively.Compared with the solvent reflux extraction method(SRE) ,the proposed method was simple,and showed high extraction efficiencies.关键词：Delphinium anthriscifolium Hance;pressurized microwave-assisted extraction;belsoline;eldeline;orthogonal test
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发布时间： - 摘要：The influence of different background ultraviolet absorption reagents on the determination of alkyl sulfonates without ultraviolet absorption was investigated in the paper.The analytes were separated on a reversed-phase C18 column using background ultraviolet absorption reagents-organic solvent as mobile phase by high performance liquid chromatography with indirect ultraviolet detection.The rule and mechanism of different background ultraviolet absorption reagents in the determination and retention of alkyl sulfonates were investigated.The results showed that different types of background ultraviolet absorption reagents in the determination of alkyl sulfonates lead to different types of chromatographic peaks of alkyl sulfonates.When the alkyl sulfonate was determined with the cationic background ultraviolet absorption reagent，the peaks of samples were all positive.On the other hand，when the alkyl sulfonate was determined by the anionic or the amphiprotic background ultraviolet absorption reagent，the peaks of samples were all inverted.Through the comparison of different background ultraviolet absorption reagents，it could be found that the chromatographic peak is better for the determination of alkyl sulfonates using cationic ultraviolet absorption reagents.Among them，the imidazolium ionic liquid is the best and its detection response value is higher.关键词：high performance liquid chromatography(HPLC);indirect ultraviolet detection;alkyl sulfonates;imidazolium ionic liquids
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发布时间： - 摘要：An amplified luminescent proximity homogeneous assay(AlphaLISA) was developed for the determination of four kinds of β agonists(clenbuterol,salbutamol,brombuterol,terbutaline) in pork.The analytes were stepwise extracted with ammonium acetate and β-glucuronidase/sulfatase,the extract was columned and concentrated to dryness,redisolved in buffer.Samples were reacted with botinylated antigen,antibody,donor beads and acceptor beads,and detected by AlphaLISA with matrix standard curve.As a result,there are good linear relationships in the concentration range of 0.1-500 ng/mL，with correlation coefficients larger than 0.98.The cross-reactivities for clenbuterol,brombuterol,terbutaline were 143.3%,179.2%and 95.6%,respectively,and the limits of detection(LOD) were 0.03-0.08 ng/mL.The average recoveries of four compounds at spiked levels of 0.5,10,20 μg/kg were in the range of 82.5%－115.9%with relative standard deviations(RSD) not less than 12.0%.The method is simple,rapid and accurate,and is suitable for the detection and screening of β-agonists in pork.关键词：AlphaLISA;β-agonists;pork
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发布时间： - 摘要：A RP-HPLC method was developed for the determination of four B-vitamins(VB1,VB2,VB3，VB6) in currant after treated with SO2.The effects of mobile phase,pH value and gradient elution procedure on chromatographic separation were studied.The mobile phase was a mixture of pH 4.4 buffer solution and acetonitrile.Under the optimal conditions,the detection limits of four B-vitamins in currants were in the range of 0.013-0.064 mg/L.The linear ranges were between 0.1 mg/L and 20 mg/L with correlation coefficients(r2) larger than 0.999.The average recoveries for the method were in the range of 83.0%-101.4%while RSDs were in the range of 0.6%-4.8%.At the same time,the contents of these vitamins before and after treated with SO2 were investigated.The results showed that the content of VB6 in currant was the highest and that of VB1 was lower.But the change of VB1 content in currant treated with SO2 was the largest,and the contents of other three species of B-vitamins changed very little.The method showed the advantages of simplicity,rapidness,accuracy and reproducibility,and was suitable for the determination of B-vitamins in currants.关键词：high performance liquid chromatography(HPLC);SO2;B-vitamins;currants
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- 0
发布时间： - 摘要：A new method was developed for the determination of 5 allergens(cinene,linalool,citral,benzyl acetate,cinnamaldehyde) in disposable product for infants by liquid-liquid micro-extraction combined with GC-MS.Samples were extracted with acetonitrile.The extract was dispersed with water,salted out with NaCl,and concentrated with tetrachloromethane(CCl4).The analytes were detected by GC-MS with the external standard method.The calibration curves were linear in the range of 0.01-10 mg/kg,wtih correlation coefficients more than 0.99.The detection limits were in the range of 0.01-0.1 mg/kg.The spiked recoveries were in the range of 78.7%-106%,with RSDs of 2.4%-11.3%.The result comfirmed that the method was accurate,rapid and sensitive,and was suitable for the determination of 5 allergens in disposable product for infants.关键词：disposable product for infants;allergen;liquid-liquid micro extraction;GC-MS
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- 1
发布时间： - 摘要：In this paper,ZnO modified pencil graphite electrode(ZnO/PGE) was prepared by dropping ZnO nanoparticles on the surface of pencil graphite electrode(PGE)The ZnO/PGE showed an unexpectedly electrogenerated chemiluminescent behavior in NaOH solution with potassium persulfate(K2S2O8) as a coreactant.The possible mechanism of electrogenerated chemilumnescence(ECL) was investigated.Based on the principle that ECL of ZnO/PGE was quenched in the presence of phenol,an ECL sensor was developed for the detection of phenol.The ECL intensity was linearly changed with the logarithm of phenol concentration in the range of 2×10-8-2×10-6 mol/L,and the detection limit(S/N=3) was 1×10-8 mol/L.With the advantages of broad linear range,good reproducibility and storage stability,the proposed method was applied in the analysis of phenol in industrial waste water,with recoveries of 96.5%-104.5%.关键词：ZnO;phenol;electrogenerate chemiluminescence(ECL);pencil graphite electrode
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发布时间： - 摘要：The low-abundance proteins play an important role in the biological activity of living organisms,involving in many physiological or pathological processes,such as metabolism,transcription and translation.Therefore,the analysis and identification of low-abundance proteins are vital in the study of proteomics.Combinatorial peptide ligand library(CPLL) is an effective method for the enrichment of low-abundance proteins,and the detection and identification of low-abundance proteins could be achieved after treated by CPLL.According to studies on the CPLL reported in recent years,its applications in different fields including the studies on low-abundance proteins in human,animal and plant protein samples were reviewed.The main purpose of this review is to provide a reference for future researches and applications of CPLL.关键词：low-abundance proteins;combinatorial peptide ligand library;proteomics;research progress;review
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发布时间： - 摘要：The analysis of carbohydrate structure and composition plays a vital role in the study of structure-activity relationship of carbohydrates.Hydrophilic interaction chromatography(HILIC) could be used to separate polar compounds like carbohydrates with satisfactory resolution.The stationary phase and retention mechanism of HILIC column commonly used in carbohydrates analysis were introduced.The effects of strong elution solvent ratio,mobile phase pH value,buffer salt concentration and column temperature on separation were also discussed.Application examples in analysis of monosaccharide composition,disaccharide composition of glycosaminoglycans,polymerization degree of oligosaccharides,glycosides,glycolipids,sugar alcohols and N-/O-glycans by HILIC were illustrated in this paper.关键词：hydrophilic interaction chromatography;stationary phase;retention mechanism;carbohydrate analysis;review
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