最新刊期
      卷 31 ， 期 9 ， 2012
      • Vol. 31, Issue 9, Pages: 1017-1030(2012)
        摘要：In this paper,16 laboratories were chosen through open recruitment on the internet and verifications of their qualifications,and international AOAC collaborative study protocol and blind samples for determinations as well as testing materials necessary were shipped to each laboratory by AOAC Study Director in accordance with the guidelines of AOAC method evaluation.The collaborative laboratories tested the blind samples and sent back the analytical results to AOAC Study Director.The statistical results showed that two labs of them should be eliminated as they deviated from the protocol in some major operational procedures.For the remaining 14 labs：GC-MS/SIM （GC-MS/MS）：RSDr＜8% accounts for 100%,RSDR＜16% makes up 57.5%，RSDR＜25% accounts for 92.5%,HorRat values that are less than 1.0 account for 80.0%，HorRat values that are less than 2.0 account for 97.5%;LC-MS/MS:RSDr＜8% accounts for 65.0%，RSDr＜15% makes up 97.5%,RSDR＜16% accounts for 35.0%，RSDR＜25% makes up 95.0%,HorRat values that are less than 1.0 account for 92.5%,HorRat values that are less than 2.0 account for 97.5%1 220 target pesticide calibration curves were established,1 132 with r2 values satisfying the requirements of ≥0.995,making up 92.8%.Target ion abundance data were 3 600,3 443 is conforming to EU standard in abundance ratio,accounting for 95.6%.By these results,the method was proved to have good repeatability and reproducibility,and was suitable for the determination of multiple pesticide residues in tea.  
        关键词：tea;pesticide residues;pre-collaborative study   
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      • Vol. 31, Issue 9, Pages: 1031-1036(2012)
        摘要：A novel method was developed for the simultaneous determination of three trace non-volatile impurities，capsaicin，dihydrocapsaicin and piperine in gutter oils using liquid chromatography-tandem mass spectrometry(LC-MS/MS).Analytes were extracted with hexane saturated acetonitrile，then separated on a Thermo BDS Hypersil C18 column(100 mm×2.1 mm，2.4 μm)by gradient elution.The qualitative and quantitative analysis of target compounds were carried out by electrospray ionization mass spectrometry under the positive mode with multiple reaction monitoring(MRM).The correlation coefficients of three calibration curves were over 0.99 in the corresponding concentration range.The average recoveries of three analytes varied from 65% to 89%，with relative standard deviations(RSDs) of 5.3%-16.1%.The limits of detection(LOD，S/N≥3) and quantitation(LOQ，S/N≥10) were 0.03 μg/kg and 0.1 μg/kg，respectively.The results of the real sample tests showed that this method is simple，rapid，sensitive and reliable，and could be used as one of the identification means for gutter oils.  
        关键词：liquid chromatography-tandem mass spectrometry(LC-MS/MS);gutter oils;capsaicin;dihydrocapsaicin;piperine;identification   
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      • Vol. 31, Issue 9, Pages: 1037-1041(2012)
        摘要：Investigation on the adsorption of proteins on graphene is very important for the biomedical applications and safety evaluation of graphene materials.In this work，the adsorption of cytochrome c，a protein involved in cell apoptosis，on graphene oxide was studied.The morphology of graphene oxide and its protein complex were characterized by atomic force microscopy，indicating that the adsorption occured in multilayer mode.The adsorption kinetics and isotherm were also studied，revealing a very high adsorption capacity(1 978 mg/g) of cytochrome c on graphene oxide.Finally，it is found that the enzymatic activity of cytochrome c only changed slightly before and after the adsorption on graphene oxide，suggesting that the conformation of cytochrome c was maintained during the adsorption process.This work is expected to provide some important data for biomedical applications and safety evaluation of graphene materials.  
        关键词：graphene;cytochrome c;adsorption;protein;enzymatic activity   
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      • Vol. 31, Issue 9, Pages: 1042-1050(2012)
        摘要：High quality PEI-capped Mn-doped ZnS QDs were prepared via a microwave and ultrasonic-assisted synthesis for room temperature phosphorescence detection of guanosine 5’-triphosphate(GTP).Such QDs showed high selectivity and sensitivity for GTP，and could distinguish GTP from adenosine triphosphate(ATP)，cytidine triphosphate(CTP)，uridine triphosphate(UTP)，adenosine diphosphate(ADP) and adenosine monophosphate(AMP).The room temperature phosphorescence response of the PEI-capped Mn-doped ZnS QDs for GTP reached equilibrium in 3 min.PEI-capped Mn-doped ZnS QDs gave a detection limit(3s) of 0.6 μmol/L for GTP.The developed phosphorescence probe favors biological applications since the interference from scattering light and autofluorescence can be effectively eliminated.The developed method has been successfully applied for the room temperature phosphorescence detection of GTP in cancer cell extract.  
        关键词：Mn-doped ZnS quantum dots;microwave and ultrasonic-assisted synthesis;room temperature phosphorescence;guanosine 5’-triphosphate   
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      • Vol. 31, Issue 9, Pages: 1051-1057(2012)
        摘要：The volatile components in the leaf,stem and root of Solidago Canadensis L.were analyzed by gas chromatography-quadrupole time of flight mass spectrometry(GC-QTOF MS).Total of fifty four compounds were found using a multidimensional qualitative analysis approach consisting of NIST MS search,accurate mass measurement retention index and area normalization.Terpenes such as limonene,pinene,germacrene D were identified as the major volatile components existing in the root,stem and leaf of Solidago Canadensis L.Results showed that GC-QTOF MS with high separation efficiency and high mass accuracy could be widely applied in the detection of the volatile components in complicated matrices.And the multidimensional qualitative approach could simplify molecular characterization and structural confirmation.  
        关键词：gas chromatography-quadrupole time of flight mass spectrometry(GC-QTOF MS);structural confirmation;Solidago Canadensis L.;volatile component   
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      • Vol. 31, Issue 9, Pages: 1058-1063(2012)
        摘要：A simple，controllable and feasible method to prepare gold nanoflowers(AuNFs) with a highly complex three-dimensional structure was developed by using dopamine(DA) as reducing agent and capping agent to react with gold chloride acid(HAuCl4) in 70 ℃ within 10 min.It was found that the freshness and concentration of dopamine solution were the key factors in controlling the morphology of AuNFs，while the concentration of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) could be used to adjust the size of AuNFs，and the introduction of the common surfactants such as Triton X-100，Tween-80，CTAB could also affect the morphology of AuNFs.Because of the complex three-dimensional structure，AuNFs may have strong electric field at edges and corners，which makes AuNFs have potential applications in catalysis，photothermal therapy.  
        关键词：dopamine;gold nanoflowers(AuNFs);morphology   
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      • Vol. 31, Issue 9, Pages: 1064-1069(2012)
        摘要：A reagentless amperometric immunosensor was built on a novel self-assembled sandwich nanohybrid of functionalized multi-walled carbon nanotubes（MWCNTs）,which was proposed by the following methods.Firstly,MWCNT functionalized by Nafion（N-MWCNTs） was obtained by ultrasonic method and dropped onto the surface of glass carbon electrode.After that,based on the ion exchange reaction,thionine（Thi） could be absorbed stably by both carboxylic MWCNT and cation exchanger Nafion.Following that,thionine covalently linked the nanocomposite of MWCNT functionalized by gold nanoparticles（GN-MWCNTs） through the electrostatic force with the amino groups of Thi to form the sandwich self-assembled film,which was utilized to immobilize the antibodies.After blocked by bovine serum albumin（BSA） for 30 min,the immunosensor towards for the detection of α-１-fetoprotein was successfully prepared.The α-１-fetoprotein（AFP） was immobilized on the double enlarged specific surface by GN and MWCNTs.This regentless immunosensor displayed a sensitive detection owning to the conductive electronic transformation channel constructed by the sandwich film of functionalized MWCNTs.Cyclic voltammetry（CV） was utilized to characterize the self-assemblied process of the immunosensor.And the microstructure of obtained material was observed by transmission electron microscopy（TEM）.Furthermore,the experimental conditions were optimized,including incubation time,incubation temperature and pH value of the detection solution.The proposed immunosensor presented an amplified sensitivity for the detection of AFP with a detection limit（S/N=3） of 0.12 ng?mL-1.Meanwhile,the proposed immunoassay also presented good stability,selectivity and storage stability.  
        关键词：immunosensor;carbon nanotube;MWCNT functionalized by gold nanoparticles;α-１-fetoprotein   
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      • Vol. 31, Issue 9, Pages: 1070-1074(2012)
        摘要：A fully automated online multidimensional separation system，which is based on a reversed phase-strong cation exchange(RP-SCX) biphasic trap column，was developed for the large scale phosphorylation analysis of human liver.Compared with the conventional online SCX-RP system and off-line mode，the biphasic column can reduce the sample loss and improve the detection sensitivity.This system was applied in the large scale phosphorylation analysis of human liver and a total of 3 082 unique phosphopeptides，including 3 056 unique phosphorylation sites corresponding to 1 332 phosphoproteins were identified under the FDR＜1%.The molecular function and motif analysis of phosphoproteins has revealed the important role of phosphorylation in the liver physiological functions.  
        关键词：online multidimensional separation;phosphopeptides;proteomics;human liver   
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      • Vol. 31, Issue 9, Pages: 1075-1080(2012)
        摘要：A novel binary porogenic agent of Pluronic F127/dodecylamine was used in the fabrication of C8 hybrid monoliths by the two-step acid/base sol-gel transition.Scanning electron microscope images showed that the morphology varied from particle aggregates to co-continuous structure and the sizes of macropore and skeleton decreased when F127 was added.In the meantime,F127 was also helpful for the regulation of the mesopore of the monoliths.As a result,a more fine morphology with a higher surface area was obtained which was more beneficial for small molecules analysis.In addition,the time of sol-gel transition was prolonged about 10 min when reducing the amount of dodecylamine,which provided enough time for filling step and improved the column-to-column reproducibility.The permeability of the C8 hybrid monolithic columns was calculated to be 2.53×10-13 m2 which was still satisfactory compared to the other kinds of monolithic columns.Pressure test was passed in a wide range of flow rate of mobile phase and the van Deemter curves for benzene and toluene were acceptable.The C8 hybrid monolith of the binary porogenic agent had a plate number of 49 000/m which was much higher than that of C8 monolith fabricated by traditional method without Pluronic F127.The performance of the C8 hybrid monoliths was investigated in nanoliquid chromatography-ultraviolet/mass spectrometry（nanoLC-UV/MS） mode.Good peak shapes were obtained in the analysis of polycyclic aromatic hydrocarbons and alkylbenzens.Seven kinds of microcystins and Nod-R were also separated by the C8 hybrid monoliths.As a conclusion,the new C8 hybrid monolithic columns were easier in preparation,more convenient in the control of morphology,higher in column efficiency,and more useful in analysis of small molecules.  
        关键词：binary porogenic agent;hybrid monolith;Pluronic F127;dodecylamine   
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      • Vol. 31, Issue 9, Pages: 1081-1088(2012)
        摘要：The advantages and applications of NMR in the analysis and identification of pharmaceutical materials were discussed,based on paper investigation and our own experience.The real cases showed that NMR could play an unique role in the pharmaceutical assay due to its distinctive technical characteristics,such as multi-methods available,plenty of information provided and flexibility of qNMR.In these cases,the main components in each of mixtures were identified and their contents（or relative cintens） were determined simultaneously by NMR techniques within a relatively short time.  
        关键词：qNMR;selective NMR experiments;dosy;pharmaceutical assay   
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      • Vol. 31, Issue 9, Pages: 1089-1094(2012)
        摘要：An anion-exchange monolithic column was prepared by a polymerization inside a stainless steel tube(150 mm×4.6 i.d.mm),taking glycidyl methacrylate(GMA) as functional monomer,ethylene dimethacrylate(EDMA) as cross-linking agent and in the presence of 1,4-butanediol,1-propanol and water as the porogen solvents and azobisisobutyronitrile(AIBN) as a suitable initiator.Introduction of anion-exchange sites were achieved by reacting with tirmethylamine.Under the optimized reaction conditions and the modified conditions,the chromatographic characteristics of the prepared anion-exchange columns were further studied,and the separation of 5 common anions (such as,acetate,bromate,nitrite,bromide,nitrate) on the prepared anion-exchange column was investigated.The prepared column exhibits more advantages such as simple preparation and low cost,and could be coupled with a commercial ion chromatography system directly,which will be favorable for more applications and investigations.  
        关键词：Anion-exchange;monolithic column;preparation;ion chromatography(IC);separation of anions   
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      • Vol. 31, Issue 9, Pages: 1095-1009(2012)
        摘要：Erythropoietin（EPO） is one kind of important hematopoietic growth factor,which is sometimes abused by endurance athletes to enhance performance since it can improve the oxygen-carrying capacity of blood.Benefited from the specific recognition and the amplification capability of aptamer,an analysis strategy for the quantification of recombinant human erythropoietin-α（rHuEPO-α） by magnetic separation-based aptameric real-time quantitative PCR was established.As for the serious interference effects caused by the high abundant proteins in the real biological samples such as urine and plasma et al,according to the base pairing principle,two complementary strands which could respectively bind primer regions at both ends of aptamer in this study were designed and synthesized,followed by evaluation by electrophoretic mobility shift assay（EMSA）,and the optimal sequence was linked to streptavdin-paramagnetic particles（SA-PMPs） via the biotin-streptavidin interaction,thus the formed probes could efficiently capture the aptamer-target complexes from complicated matrix.The results showed that the established analysis strategy could be successfully applied in the determination of the concentration of rHuEPO-α in human serum with this sample pretreatment,with a limit of detection（LOD） of 25 pmol/L and a linear range from 50 pmol/L to 50 nmol/L.  
        关键词：aptamer;erythropoietin;analysis strategy;capture probe;real-time quantitative PCR   
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      • Vol. 31, Issue 9, Pages: 1100-1104(2012)
        摘要：A micellar electrokinetic capillary chromatographic(MEKC) method was developed for the separation and determination of 13 artificially synthesized pigments,including ten water-soluble and three fat soluble substances(e.g.auramine O,Sudan Ⅱ,Sudan Ⅰ,Sudan Ⅲ&Ⅳ,acid orange,brilliant,acid red 92,erythrosine,uranine,allura red,acid red 1,indigo and sunset yellow) in food.The parameters including buffer composition,pH value,concentration of boric acid and SDS were optimized by orthogonal experiment method.At the same time,effects of organic modifier,separation voltage and temperature on the separation were investigated.The optimal conditions were as follows:separation column:a 75 μm×58.5 cm uncoated fused silica capillary;buffer:40 mmol/L sodium borate(pH 9.5);BGE solution:20 mmol/L SDS-30% acetonitrile;detection wavelength:220 nm,run voltage:25 kV;temperature:25 ℃,and the sample was injected at 50 MPa for 5 s.Under the optimal conditions,the linear relationship between concentration and peak area for each of these analytes was obtained in the concentration range of 3-200 mg/L,with correlation coefficients larger than 0.99.The method was applied in the determination of 13 artificially synthesized pigments in samples of spiced duck wings,dried bean milk cream in tight rolls,ketchup and chili powder,with recoveries between 98% and 104%.The limits of detection ranged from 3.0 mg/L to 16.0 mg/L.The results indicated that the method was simple and accurate,and was suitable for the simultaneous determination of the thirteen pigments in food samples．  
        关键词：micellar electrokinetic capillary chromatography(MEKC);artificially synthesized pigment;food   
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      • Vol. 31, Issue 9, Pages: 1105-1109(2012)
        摘要：Cetyltrimethyl ammonium bromide(CTAB) was attached on gold nanorods(AuNRs) as a stabilizing agent,which can enrich the plant polyphenolic compounds(HQ) on the surface of gold nanorods and lead to weaken the fluorescent intensity of gold nanorods by hydrophobic effect.When different polyphenolic compounds were added to gold nanorods system,the fluorescent intensity of AuNRs in 719 nm was decreased significantly.Under the experimental conditions of 20% methanol(pH 5.0-6.0),the fluorescent intensity of AuNRs as fluorescent probe was linearly related to the concentration of three polyphenolic compounds(mangiferin,daphnetin and resveratrol).In this way,a new method for the analysis of three polyphenolic compounds with sensitivity,simplity and quickness was established.The detection limits of three polyphenolic compounds were 5.0×10-8,8.0 ×10-8,2.0 ×10-7mol?L-1,respectively.  
        关键词：gold nanorods;fluorescence analysis;polyphenolic compounds   
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      • Vol. 31, Issue 9, Pages: 1110-1114(2012)
        摘要：A quartz crystal microbalance(QCM) method was developed for the determination of heavy metal ions by using MBA functionalized gold nanoparticles as signal enhancer,and ercaptoethylamine-modified gold electrode with the help of self-assembly monolayer(SAM) techniques.In a typical experiment,cadmium(Ⅱ) bounds with amino-groups on gold electrode through complexation.After that,MBA modified nanoparticles were assembled onto gold electrode through complexation of carboxyl group of gold nanoparticles to cadmium(Ⅱ),thus leading to a mass change which could be used to detect cadmium(Ⅱ).Determinations of lead(Ⅱ),mercury(Ⅱ) and copper(Ⅱ) was also studied using this strategy.The results showed that the methodology has low detection limit,high sensitivity and good reproducibility.  
        关键词：quartz crystal microbalance(QCM);gold nanoparticles;heavy metal ions   
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      • Vol. 31, Issue 9, Pages: 1115-1119(2012)
        摘要：A headspace solid-phase microextraction(HS-SPME) coupled with gas chromatography-mass spectrometric(GC-MS) method was developed for the analysis of four cyclic(D3，D4，D5 and D6) and two linear volatile methyl siloxanes(L3 and L4) in aqueous samples.Parameters affecting the performance of HS-SPME/GC-MS，including fiber coating，desorption time，pH value，extraction temperature，extraction time and salinity，were studied.The optimum conditions were as the follows:40 mL of water sample was placed in a 60 mL headspace vial containing a magnetic stir bar.40 μL of 500 μg/L internal standard(M4Q) and 0.1 g/mL NaCl were added into vial，and then the vial was tightly sealed with a Teflon septum.HS-SPME with PDMS/DVB fiber was carried out at 24 ℃ for 45 min.After the extraction，the fiber was removed from the vial，and inserted into the injection port of GC-MS system for thermal desorption(200 ℃，2 min) and analysis.The method detected limits(LOD) of six target compounds ranged from 2.6 ng/L to 7.8 ng/L.Their recoveries ranged from 82% to 96% with relative standard deviations(RSDs，n=5) of 1.1%-7.9%.The results indicated that the method was simple，rapid，sensitive，and was suitable for the determination of volatile methyl siloxanes in aqueous samples.With the optimized method，the six target compounds were measured in 24 aqueous samples collected from Qinghe WWTP and Qinghe River.L4，D3，D4，D5 and D6 were detectable with concentrations of 0.07-0.21，0.07-0.59，0.05-4.30，0.02-7.60，0.04-7.13 μg/L，respectively.  
        关键词：aqueous sample;volatile siloxanes;HS-SPME;GC-MS   
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      • Vol. 31, Issue 9, Pages: 1120-1125(2012)
        摘要：A morin/graphene modified glassy carbon electrode(M/GN/GCE) was fabricated by electro-polymerizing morin(M) on the surface of graphene nanosheets(GN).Taking the dopamine(DA) and ascorbic acid(AA) as model compounds, the electrochemical behaviors of the modified electrode were investigated by using cyclic voltammetry(CV) and differential pulse voltammetry(DPV).In pH 7.0 phosphate buffer solution(PBS),the anodic peak potentials of DA and AA were 0.172 V and-0.183 V,respectively,with a peak to peak separation up to 355 mV.In comparison with bare glassy carbon electrode(GCE),morin modified glassy carbon electrode(M/GCE) and graphene modified glassy carbon electrode(GN/GCE),the M/GN/GCE has superior electrocatalytic activity toward the oxidation of DA.The results demonstrated that the aromatic structure of M endows it strongly adsorption on GN via π-π stacking which could improve the selectivity and sensitivity for the determination of DA in the presence of AA.The peak currents obtained from DPV were linearly related to the concentrations of DA in the range of 2.0×10-8-5.5×10-4 mol/L with a detection limit of 9.0×10-9 mol/L.  
        关键词：morin;graphene;modified electrode;dopamine;selective determination   
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      • Vol. 31, Issue 9, Pages: 1126-1131(2012)
        摘要：The analytical method for 16 USEPA priority polycyclic aromatic hydrocarbons(PAHs) in soil was optimized in this study,and an integrated quality control(QC) system was established to resolve the problems occurring in PAHs analysis,such as the lower recoveries of benzo(a)pyrene(BaP),unsatisfactory clean-up efficiency for samples in complex matrix,volatilization loss and environmental background of naphthalene(Nap) and phenanthrene(Phe).The analysis procedure commenced with accelerated solvent extraction(ASE),followed by solid phase extraction(SPE) clean-up and gradual condensation in vacuum.Gas chromatography-mass spectrometry(GC-MS) was used for measurement.Deuterated benzo(a) pyrene(BaP-d12) was used as an indicator of recovery in analysis.Three normal phase SPE materials were attempted to separate PAHs in samples,the results indicated that BaP was degraded when passing through florisil.Isotope dilution quantification was recommended to reduce the uncertainty of BaP analysis.Alumina was unsuitable for clean up as for its strong adsorption to PAHs,but silica gel was proved to be the appropriate SPE material among the three candidates.The detection limits for the instrument and the analytical method were in the ranges of 0.26-5.7 pg and 0.067-0.97 ng/g(dry weight),respectively.Recoveries of PAHs in spiked soil ranged from 71% to 122%,with RSDs of 1.6%-8.3%.The method was applied in the analysis of 7 farmland soil samples collected from electronic waste combustion area.The concentrations of PAHs were in the range of 28-283 ng/g(dry weight),the recoveries of BaP-d12 ranged from 90% to 124%,which all fell within the acceptable range set by the QC system.  
        关键词：polycyclic aromatic hydrocarbons;soil;quality control;solid phase extraction;GC-MS;benzo(a)pyrene   
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      • Vol. 31, Issue 9, Pages: 1132-1136(2012)
        摘要：The microstructure and texture evolution of electron-beam welded Al-Zn-Mg-Cu alloy were investigated using field emission scanning electron microscopy，transmission electron microscopy and electron back-scatter diffraction（EBSD）.The results indicated that the weld nugget zone was composed of equiaxed grains with an average grain size of 3-8 μm.The second phases are mainly distributed along the grain boundaries.After T6(solution treated and aged） treatment，Most of the second phases in weld nugget were dissolved into α（Al）.The base metal exhibits the typical<111> and<001> fibre textures in extrusion direction，and the sharpness slightly decreased after T6 treatment.No significant texture was observed in the nugget zone.  
        关键词：Electron-beam welding;Al-Zn-Mg-Cu alloy;texture   
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      • Vol. 31, Issue 9, Pages: 1137-1141(2012)
        摘要：A liquid chromatographic method was established for the determination of 20 disperse dyes in drink and wine.The chromatographic conditions，including analysis column types，composition of mobile phase，detection wavelengths， were optimized.The sample was extracted with dichloromethane-ethyl ether mixed solution，and the separation of 20 dyes was performed on a C18 column，by using solution of 10 mmol/L ammonium acetate as mobile phase，at detection wavelengths of 430，570,640 nm.Under the optimal conditions，the calibration curves were liner in the range of 0.5-5.0 mg/L with correlation coefficients higher than 0.999.The recoveries of disperse dyes from drink and wine at spiked levels of 0.1,0.2,0.4 mg/kg were in the range of 80%-99% with RSDs of 0.1-9.1%.The result showed that the method was simple，rapid and accurate，and was suitable for the determination of disperse dyes in drink and wine.  
        关键词：disperse dyes;drink;wine;liquid chromatography   
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      • Vol. 31, Issue 9, Pages: 1142-1145(2012)
        摘要：Atmospheric water vapor exhibits strong spectral features in the far-IR region，particularly below 400 cm-1.Therefore,water vapor absorption bands may severely obscure important sample features in a far-IR spectrum.In this article,humidity compensation was applied to remove water vapor bands during the acquiring process of a far-IR spectrum.The scanning procedure of a single-beam sample spectrum was divided into two stages.At the first stage,the appearance of water vapor peaks is allowed and the absorption direction and intensity of water vapor bands can be observed easily at the end of this stage.Then,the relative humidity in the sample compartment of the spectrometer has to be changed by a dry or a wet air supply depending on the absorption direction of water vapor bands.For example,if the absorbance of water vapor is negative at the end of the first stage,then a wet air supply is necessary.After the relative humidity changes to a certain extent,water vapor peaks will become smaller and smaller with the increase in scanning number during the second stage.By this way,water vapor noise can be removed progressively and completely at last.  
        关键词：far infrared spectrum;water vapor noise;humidity compensation;removing water vapor bands   
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      • Vol. 31, Issue 9, Pages: 1146-1150(2012)
        摘要：A method was developed for the separation and determination of 12 chiral polychlorinated biphenyls(PCBs),i.e.CB 45,CB 84,CB 91,CB 95,CB 131，CB 132,CB 136,CB 149,CB 171,CB 174,CB 176 and CB 183,in biological samples.The target chemicals were Soxhlet extracted ,cleaned up by gel permeation chromatography and multi-layer silica alumina column,and were further fractioned with a Florisil column.The chiral PCBs were identified and quantified by gas chromatography–mass spectrometry with electron impact ion source(GC-EI/MS).The peak resolutions of these chiral congeners ranged from 0.5 to 2.1.The relative standard deviations of the calculated enantiomeric fractions(EFs) in triplicates were less than 2%.The enantiomers of CBs 84,CB 91 and CB 174 in the standard solutions were separated by two different chiral columns.There was a slight discrepancy in the calculated EFs between the two columns,with relative standard deviations of 1.2%,0.2% and 0.2% for CB 84,CB 91 and CB 174,respectively,suggesting the high degree of accuracy and efficiency of the established method.  
        关键词：gas chromatography-mass spectrometry;polychlorinated biphenyl;biological sample;chiral;enantiomer;separation   
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      • Vol. 31, Issue 9, Pages: 1151-1160(2012)
        摘要：The development and applications of ambient ionization mass spectrometry(AI-MS) that realized ionization under ambient conditions without sample pretreatment have become a frontier field in mass spectrometry and deserved much attention over the last few years.This review summarizes the basic principle and traits，application progress of ambient ionization mass spectrometry.Moreover，it introduces the fundamental characteristics and representative applications of gas flow assisted ambient ionization mass spectrometric technologies involved the author′s independent-developed air flow assisted ionization(AFAI).The future and trends of ambient ionization mass spectrometry are also discussed.  
        关键词：ambient ionization;mass spectrometry;gas flow;air flow assisted ionization;review   
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      • Vol. 31, Issue 9, Pages: 1161-1169(2012)
        摘要：Compared with bulk molecularly imprinted polymer，molecularly imprinted microspheres（MIMs） exhibit more uniform size and much better dynamic characteristics.Thus，MIMs are widely used in the applications of solid-phase extraction（SPE），chromatographic separation，biosensor and drug delivery system.The main synthesis methods of MIMs are suspension polymerization，multi-swelling polymerization（MSP） and precipitation polymerization（PP）.In this review，the research literatures on MIMs published in recent 10 years were tracked.The three synthesis methods of MIMs were summarized and commented.The advantages and disadvantages of those synthesis methods were compared.Meanwhile，the applications of MIMs in SPE were reviewed，and the prospect of synthesis and applications of MIMs was also put forward.  
        关键词：molecularly imprinted microspheres（MIMs）;suspension polymerization;multi-swelling polymerization;precipitation polymerization;solid-phase extraction;review   
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      • Vol. 31, Issue 9, Pages: 1170-1177(2012)
        摘要：The fundamental behaviors of gold electrode in three aspects including influence factors of electrochemical behaviors,surface adsorption of anions and calculation of electrode area were reviewed.The discussion on the fundamental behavior of gold electrode is of important scientific significance in the research of related fields.  
        关键词：gold electrode;influence factors of electrochemical behavior;surface adsorption of anions;electrode area;review   
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      • Vol. 31, Issue 9, Pages: 1178-1183(2012)
        摘要：Graphene is an atomically thin honeycomb lattice of carbon atoms.It comprises a single layer of SP2-hybridized carbon atoms arrange in six-membered rings.As a new carbon-based nanomaterial after carbon nanotube，graphene could be considered as one of the ideal absorption materials with superior chemical stability，thermal stability and high specific surface area.Graphene oxide(GO) possesses rich oxygen-contained groups on its surface.Most of the graphene used nowadays is produced from the reduction of graphene oxide.In recent years，GO and graphene have been applied in the separation and enrichment of organic compounds，mental ions and biological molecules.In this paper，the preparation methods of GO and graphene and their applications in sample pretreatment techniques such as solid-phase extraction(SPE)，solid-phase microextration(SPME)，magnetic solid-phase extraction(MSPE)，stir bar sorptive extraction(SBSE) were reviewed.  
        关键词：graphene oxide;graphene;preparation;sample pretreatment   
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      • Vol. 31, Issue 9, Pages: 1184-1190(2012)
        摘要：The development of highly selective methods for the analysis of proteins in biosystems is crucial for studying their structures and biological functions.These methods will offer new opportunities to explore complex disease-related biological processes at the molecular level both in vitro and in vivo.Herein，recent progress in highly selective analysis of proteins is summarized focusing on the molecular-probe based approach，colorimetric detection as well as microfluidic technique.  
        关键词：protein;peptide probe;molecular recognition;highly selective analysis   
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      • Vol. 31, Issue 9, Pages: 1191-1198(2012)
        摘要：Petroleum is one of the most important energy resources on the earth.It is also a kind of chemical raw material with high quality.Petroleum products could be found anywhere in our daily life.In recent years,due to the continualy increasing of nationwide crude oil processing capacity and the increasing difficulty of processing,more and more attention has been focused on the issue of rapid crude oil assay.Furthermore,with the density increasing of crude oil worldwide,the ratio of heavy oil processing in national refinery is increased,leading to more refined and effective processing requirements of heavy oil,so the rapid assay of heavy oil is also urgent.The crude oil assay means a comprehensive analysis on the processing performance of crude oil and the possible problems during the processing,which is based on the comprehensive analysis of the physical and chemical properties of crude oil.The traditional methods of crude oil assay are usually time consuming,high sample consuming and expensive,which is not suitable for the field application with high analytical requirements.The rapid development of computer technology and instrumental analysis techniques has set up a good platform for the rapid assay of crude oil.According to different analytical methods,in this paper,the developments of rapid analytical technologies in crude and heavy oil are reviewed,including near infrared-spectroscopy(NIR),infrared-pectroscopy(IR),nuclear-magnetic esonance(NMR) spectrometer and other popular analytical methods.  
        关键词：crude oil assay;instrumental analysis;near infrared spectroscopy;infrared spectroscopy;nuclear magnetic resonance   
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      • Vol. 31, Issue 9, Pages: 1199-1203(2012)
        摘要：Some new methods and technologies based on capillary electrophoresis and microfluidic chip for extraction of drugs have been presented recently.With the novel characteristic，they have been gradually developed and applied in the extraction of drugs.In this review，the application of two phase electrophoresis，microfluidic liquid-liquid and solid-liquid extraction，microfluidic filtering isolation，and microfluidic membrane separation techniques on the drugs analysis were introduced，respectively.  
        关键词：capillary electrophoresis;microfluidic chip;extraction;review   
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      • Vol. 31, Issue 9, Pages: 1204-1211(2012)
        摘要：In recent years,many consuming products containing the restricted chemical substances such as heavy metal,phthalate,azodyes,formaldehyde and volatile organic solvent,etc.have caused the quality and safety accidents in the world,resulting in countries and consumer product manufacturers massive recalls of the products which have been sold.Consumers have payed more and more attention to the restricted chemical substances in consuming products with the improvement of consumer awareness of quality and safety of consuming goods.Many countries have issued new laws and regulations on consuming goods to increase demands on the chemical substances in consuming products.This paper attempts to systematically investigate the new situation and the latest detection technology of the limited chemicals with the related technical regulations for the quality and safety of the important consuming goods,such as toy,textile clothing,electrical and electronic equipment,furniture,food contact materials,in European Union,America and China.At the same time,the paper also discusses the latest sample pre treatment technology and instrument analysis technology in order to meet the demand of production and foreign trade customs clearance inspection.  
        关键词：consumer;restricted chemical substances;regulation;test   
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      • Vol. 31, Issue 9, Pages: 1212-1216(2012)
        摘要：The situation and the main problems of the existing national standards system for performance testing of analytical instrument were analysed in this paper.Based on the current work demands，the framework of national standards system for performance testing of analytical instrument was proposed.Finally，some suggestions about how to build up a more effective national standards system were presented.  
        关键词：analytical instrument;performance testing;standards system   
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