最新刊期
卷 35 ， 期 12 ， 2016
- 摘要：A modified QuEChERS（quick，easy,cheap,effective,rugged,safe） method based on multi-walled carbon nanotubes（MWCNTs） was established for the simultaneous determination of 145 pesticide residues in limnetic products by gas chromatography- quadrupole time of flight mass spectrometry（GC-QTOF/MS）.The samples were extracted with water and acetonitrile，purified by QuEChERS with MWCNTs，determined by GC-QTOF/MS.The quantification analysis was performed with the external standard calibration.The extraction conditions，type and amount of adsorbents，acquisition rate and extraction window of GC-QTOF/MS were optimized.Under the optimal conditions，the results indicated that the calibration curves were linear（r2>0.98） in the range of 5-200μg/kg.The recoveries for 145 pesticides were in the range of 69.4%-114.2% at three spiked levels of 10，20，100μg/kg，with relative standard deviations（RSD，n=6） of 2.2%-13.8%.The limits of quantitation were in the range of 1.1-40.0μg/kg. Compared to the original QuEChERS method，the proposed method was rapid and accurate,and could significantly reduce matrix interference.关键词：gas chromatography-quadrupole time of flight mass spectrometry（GC-QTOF/MS）;multi-walled carbon nanotubes（MWCNTs）;pesticide multi-residues;limnetic product
- 1884
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- 1185
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发布时间： - 摘要：The effect of tobacco with herbal additives on the global metabolome of rat lung was studied using liquid chromatography-mass spectrometry(LC-MS).Lung samples from control rats，normal tobacco smoked rats and a certain commercial tobacco(a specific tobacco with herbal additives)smoked rats were analyzed，and the groups were exposed to smoke for one week，half month and one month，respectively.The data were processed by the method of partial least squares discriminant analysis(PLS-DA).The potential biomarkers were screened out according to VIP(Variable Importance in the Projection) and identified by database and standards.The PLS-DA results of different tobacco exposed periods showed that the metabolism of both the normal tobacco exposed group and the certain commercial tobacco exposed group were affected，mainly including phospholipid metabolism and fatty acid metabolism. In particular，two lung samples from rats exposed to normal tobacco were abnormal significantly as a result of suffering from a serious oxidative damage. Overall，especially prolonged exposure to smoke，the smoke damage of the certain commercial tobacco smoked rats was lower than that of the normal tobacco smoked rats，indicating that adding some herbal additives to tobacco could contribute at least partly to reduce the harm caused by smoking.关键词：liquid chromatography-mass spectrometry(LC-MS);metabonomics;tobacco with herbal additives;lung;biomarker
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发布时间： - 摘要：An analytical method for the simultaneous determination of 67 pesticides in vegetables and fruits by gas chromatography-triple quadrupole mass spectrometry（GC-MS/MS） with dispersive solid phase extraction（QuEChERS）.The samples were extracted with acetonitrile（containing 1% acetic acid），and then cleaned up with dispersive solid phase extraction.The extracts were determined by GC-MS/MS in multi-reaction monitoring(MRM) mode with the external standard method. The calibration curves of 67 pecitides were linear in the range of 0.005-0.24μg/mL with correlation coefficients（r2） higher than 0.99.The average recoveries at spiked concentration levels of 0.02，0.06，0.12mg/kg ranged from 60.3% to 119.8% with relative standard deviations（RSDs） of 0.5%-14.7%.The limits of detection（LOD） for the method were in the range of 0.0001-0.003mg/kg.The limits of quantitations（LOQs） were 0.0002-0.009mg/kg.The method was applied in the detection of pesticide residues of vegetables and fruits，and the result was more satisfactory comparing with that of GC，GCP/GC-MS，LC-MS/MS methods. The method showed the advantages of simplicity, quickness, high sensitivity，good selectivity，good reproducibility and stability，and was suitable for the analysis of pesticide residues in daily vegetables and fruits.关键词：gas chromatography-triple quadrupole mass spectrometry（GC-MS/MS）;dispersive solid phase extraction（QuEChERS）;vegetables;fruits;pesticide residues
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发布时间： - 摘要：A high performance liquid chromatography-tandem mass spectrometric(HPLC-MS/MS) method was established for the determination of the residual quinocetone(QCT), cyadox(CYA), bidesoxyquinocetone(BDQCT), methyl-3-quinoxaline-2-carboxylic acid(MQCA), bidesoxycyadox(BDCYA) and quinoxaline-2-carboxylic acid(QCA) in aquatic products. Samples were extracted with acetonitrile-ethyl acetate(1∶1) and hydrochloric acid solution, then cleaned up on a MAX solid-phase extraction cartridge. The separation of QCA,BDQCT,MQCA,CYA,BDCYA and QCT was carried out on a Waters XBridge C18 column using methanol, acetonitrile and 0.1% fomic acid as mobile phase. The identification of six analytes was performed by selective reaction monitoring in positive electrospray ionization, and the quantification was done by the external standard method. The calibration curves of six analytes were linear in the range of 2-500μg/L. At the fortified levels of 5-50μg/kg,the recoveries ranged from 76.3% to 94.2%,with RSDs of 4.2% to 11.7%.The limits of detection(LOD) were in the range of 0.5-1.6μg/kg and the limit of quantitation(LOQ) were 2.0-5.0μg/kg. The results showed that the method could be used to analyze simultaneously QCT, CYA and their metabolites residues in aquatic products.关键词：aquatic products;quinocetone(QCT);cyadox(CYA);metabolites;high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)
- 1950
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- 887
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发布时间： - 摘要：A novel ultra-sensitive molecularly imprinted electrochemical senor with good imprinted capacity to glyphosate was prepared by electropolymerisation on the gold electrode surface,with pyrrole(Py) as functional monomer, glyphosate(Gly) as template. The prepared electrode was characterized by cyclic voltammetry(CV), differential pulse voltammetry(DPV) and electrochemical impedance spectroscopy(EIS). The condition of polymerization,the method of eluting template,the pH value of detection andincubation time were optimized.The optimal conditions were as follows: supporting electrolyte: Britton Robison buffer solution(BR,pH 5.0),ratio of template to functional monomers:1∶5,incubation system:formic acid aqueous solution(pH 4.0),incubation time:18 min.Under the optimum experimental conditions,the prepared electrode showed rapid response, high sensitivity and good selectivity for the template molecule glyphosate. A good linear relationship between oxidation peak current and Gly concentration was obtained over the range of 5-800ng/mL with a correlation coefficient of 0.9817 and a detection limit(S/N=3) of 0.27ng/mL.The prepared sensor also showed good reproducibility and stability, the sensor was successfully applied in the determination of glyphosate in the tap water with recoveries of 78.6%-99.0%.关键词：pyrrole;glyphosate;molecularly imprinted electrochemical sensor;tap water
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发布时间： - 摘要：A new method was established to determine 14 kinds of polychlorinated biphenyls(PCBs) and organophosphate esters(OPEs) flame retardants(including TEP，TBP，TCEP，PCB18，TCPP，PCB101，PCB153，PCB138，TPhP，TEHP，PCB180，o-TTP，m-TTP and p-TTP) in leather by solid phase extraction(SPE) coupled with gas chromatography-mass spectrometry(GC-MS).The samples were ultrasonically extracted with acetonitrile，and purified with a Florisil solid phase extracting column.Analytes were successfully separated on a DB-5MS capillary column,and detected by GC-MS in selected ion monitoring mode(SIM).Analytes were qualitatively analyzed via retention time and abundance ratio of characteristic ions，and quantified by the external standard method.14 flame retardants presented favorable linearity in the respective linear ranges，with correlation coefficients(r2) more than 0.998.The detection limits(S/N=3) ranged from 25.0 μg/kg to 50.0 μg/kg，the average recoveries(n=6) were in the range of 82.0%-112.8%，and the relative standard deviations(RSDs，n=6) were 2.1%-9.4%.The method is accurate，rapid and sensitive,and is suitable for the determination of 14 flame retardants in leather samples.关键词：leather;flame retardant;solid phase extraction(SPE);gas chromatography-mass spectrometry(GC-MS)
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发布时间： - 摘要：An effective method was established for the simultaneous determination of contents of seven antibacterial agents and seven ultraviolet stabilizers in textiles using ultra-high performance liquid chromatography-orbitrap high resolution mass spectrometric(UPLC/OrbitrapHRMS) technique.Antibacterial agents and ultraviolet stabilizers in textiles were microwave assistedly extracted at 85 ℃，using methanol as extraction solvent.Then the extract was concentrated,and analyzed by UPLC-Orbitrap HRMS with the external standard method.Fourteen target compounds were separated on a Hypersil GOLD column(100 mm×2.1 mm，1.9 μm) with a gradient elution of methanol and 0.1%aqueous formic acid solution consisting of 5 mmol/L ammonium acetate.Full scan experiment was performed in the range of m/z 100-500.Fourteen target compounds were routinely detected with the accuracy all below 2×10-6(2 ppm).Among them，4-chloro-3,5-dimethyl phenol(PCMX) and triclosan were detected by orbitrap HRMS in ESI negative mode and the left twelve target compounds were all detected in ESI positive mode.The qualitative analysis was performed by the retention time and the accurate mass of quasi-molecular ion，while the quantitative analysis was performed by the peak area in extracted chromatogram.Good linearities were achieved in the respective linear ranges for each target compounds with their correlation coefficients all higher than 0.998.The spiked average recoveries ranged from 80.1%to 95.6%at three spiked levels while the relative standard deviation(RSD) varied from 2.9%to 10.5%.The limits of detection(LOD,S/N=3) changed from 0.1 μg/kg to 0.3 μg/kg.The proposed method was simple，accurate and sensitive，and could satisfy completely the demand for the determination of antibacterial agents and ultraviolet stabilizers in textiles.关键词：ultra-high performance liquid chromatography(UPLC);orbitrap high resolution mass spectrometry(Orbitrap-HRMS);4-chloro-3,5-dimethyl-phenol(PCMX);ultraviolet stabilizers;isothiazolinone;triclosan;textiles;microwave-assisted extraction
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发布时间： - 摘要：A rapid quantitative method of high performance liquid chromatograpy(HPLC) was developed for the analysis of 18 amino acids in gelatin from bovine skin and Yak skin.The steps of sample derivatization with PITC were optimized.The method was no need for drying down and extraction with organic solvent.The yak leather was enzymatically hydrolyzed at 37 ℃ for 72 h with pepsin，and then was freeze dried.The sample was then hydrolyzed with 6.0 mol/L HCl at 110 ℃.After the hydrolyzation，the solution was derivatized with phenyl isothiocyanate(PITC).Gradient HPLC separation was performed on a Shiseido Capcell Pak C18 column(4.6 mm×250 mm,5 μm) with 0.14 mol/L sodium acetate-0.5 mL/L triethylamine solution(pH 6.08，adjusted with glacial acetic acid) and 60% acetonitrile as mobile phases at a flow rate of 1 mL/min.The detection was carried out with an ultraviolet detector,and the wavelength was set at 254 nm.The calibration curves were linear in the range of 0.2-80 mg/L with correlation coefficients(r2) not less than 0.999 2.The limits of detection for the method were in the range of 0.01-0.39 mg/kg,and the average recoveries were 78.7%-121.0% with RSDs of 0.05%-12.0%.The derivatization steps were simple and sensitive，and the sample pretreatment time was short.The method was suitable for the rapid identification and determination of amino components in gelatin from bovid.关键词：gelatin from Yak;gelatin from bovine;amino acid;precolumn derivatization;phenyl isothiocyanate(PITC);high performance liquid chromatography(HPLC)
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发布时间： - 摘要：An ultra performance liquid chromatography-high resolution quadrupole time of flight mass spectrometric（UPLC-Q-TOF-MS） method was developed for the determination of four monoamine neurotransmitters including dopamine（DA），serotonin hydrochloride（5-HT），3,4-dihydroxyphenylacetic acid（DOPAC） and homovanillic acid（HVA） in mouse brains.Samples were homogenized with 30% ethanol solution（formic acid pH 5.0），freezingly centrifuged and filtered.Under the optimized chromatographic and mass spectrometric conditions，data were acquisited with electrospray ionization（ESI） and atmospheric pressure chemical ionization（APCI） composite sources in positive ion/negative ion mode.The calibration curves of four monoamine neurotransmitters showed good linearities（r＞0.999 3） within the concentration range of 0.5-1 000 μg/L.The limits of detection were in the range of 0.5-5.0 μg/L，and the average recoveries were 93.3%-101.8% with relative standard deviations（RSDs） of 1.1%-3.3%.This method showed the advantages of simplicity，efficiency，high recovery，good sensitivity and high precision，and was suitable for the determination of four monoamine neurotransmitters in brain tissue of mouse.关键词：ultra performance liquid chromatography-high resolution quadrupole time of flight mass spectrometry（UPLC-Q-TOF-MS）;monoamine neurotransmitters;mouse;brain tissue
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发布时间： - 摘要：A novel and simple mass spectrometric method based on microwave plasma torch（MPT） was developed for the rapid detection of aflatoxin B1（AFB1） in rice without sample pretreatment.The MPT mass spectra of AFB1 were obtained,and the quantitative analysis mainly was based on the characteristic fragments of AFB1（m/z 285）.The results showed that there was a good linear relationship in the concentration range of 0.5-20 μg/L with correlation coefficient（r2） of 0.999 4，and the evaluated limit of detection（LOD） was 0.12 μg/kg.The direct detection of AFB1 in some kinds of rice were conducted，with recoveries of 95.8%-107.2% and relative standard deviations（RSD，n=9） of 2.2%-10.1%With the help of principle component analysis（PCA），the moldy rice and normal rice could be rapidly distinguishedWith the advantages of rapidness and high sensitivity，the MPT-MS is a powerful tool for the high-throughput detection of moldy rice,and also shows a great potential in the monitoring of cereal and oil，animal，plant food，etc.关键词：microwave plasma torch（MPT）;mass spectrometry;aflatoxin B1（AFB1）;rice
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发布时间： - 摘要：A method was developed for the determination of 5 kinds of synthetic pigments in drinks by online solid-phase extraction coupled with high performance liquid chromatography-ultraviolet detection(online-SPE-HPLC-UV).The drinks samples were diluted with water，and filtered with 0.45 μm microporous membrane filter.Then the samples were purified on an Acclaim 120 C18 column and separated on a reversed phase column by gradient elution.The detection was performed by ultraviolet detection.The calibration curves of 5 kinds of synthetic pigments were linear in the concentration range of 0.5-20 mg/L，with correlation coefficients(r2) greater than 0.999 9.The limits of detection(LODs) were in the range of 0.02-0.08 mg/kg.The recoveries of 5 kinds of synthetic pigments at three spiked levels ranged from 94.5% to 103.0%，with relative standard deviations of 0.4%-2.7%.The research provides an effective method for the rapide determination of edible synthetic pigments in drinks.关键词：online solid-phase extraction;edible synthetic pigments;drinks;high performance liquid chromatography(HPLC)
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发布时间： - 摘要：A gas chromatography-tandem mass spectrometric(GC-MS/MS) method was developed for the determination of 5 carbamate pesticides residues，i.e，metolcarb，isoprocarb，fenobucarb，propoxur and pirimicarb in Oolong tea samples.The sample was extracted with hexane-ethyl acetate mixed solution,and the extract was cleaned up with a QuEChERS kit，including 400 mg PSA/400 mg C18/1 200 mg MgSO4.The mixed targets were separated on a Rxi-5 Sil MS(30 m，0.25 mm×0.25 μm) capillary column,and pesticide residues were identified and quantified by GC-MS/MS.5 carbamate pesticides had good linear relationships in each linear range(5-500 μg/kg for metolcarb and propoxur，1-500 μg/kg for isoprocarb，fenobucarb and pirimicarb)，and the correlation coefficients were higher than 0.99.The mean recoveries of metolcarb and propoxur in black Oolong tea at spiked levels of 5，20，100 μg/kg were in the range of 77.5%-95.4%,with RSDs(n=6) of 2.1%-6.1%.The LODs and LOQs for the two targets were 1 μg/kg and 5 μg/kg，respectively.The mean recoveries of isoprocarb，fenobucarb and pirimicarb at spiked levels of 1，20，100 μg/kg were in the range of 79.5%-102.5%with RSDs(n=6) of 2.0%-8.2%.The LODs and LOQs were 0.2 μg/kg and 1 μg/kg，respectively.With the advantages of simple operation，high sensitivity and good reproducibility,this method could meet the requirements for the determination of 5 kinds of carbamate pesticides residues in Oolong tea samples.关键词：Oolong-tea;QuEChERS;carbamate pesticides;gas chromatography-tandem mass spectrometry(GC-MS/MS)
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发布时间： - 摘要：A method was developed for the determination of ellagic acid(free ellagic acid and total ellagic acid) in strawberry by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).In this work，the free ellagic acid was extracted from strawberry with 0.1%trifloroacetric acid-methane，purified by C18 dispersive solid phase extraction，and determined by UPLC-MS/MS.Total ellagic acid was hydrolyzed to free ellagic acid with 2 mol/L trifloroacetric acid aqueous，then purified with C18 dispersive solid-phase extraction column，and determined by UPLC-MS/MS.Sample solution was separated on a C18 column by gradient elution using methanol-0.5%formic acid aqueous as mobile phase.The linear range of 10-500 ng/mL for ellagic acid was obtained，with correlation coefficient of 0.998 1.The limit of quantitation was 0.5 mg/kg for free ellagic acid and 5.0 mg/kg for total ellagic acid.The recoveries at low，medium and high spiked levels ranged from 867%to 1136%with relative standard deviations(RSD) not more than 10%.The results indicated that this approach was simple，sensitive and accurate，and was applicable for the determination of content of ellagic acid in strawberry.关键词：ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS);free ellagic acid;total ellagic acid;strawberry
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- 777
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- 4
发布时间： - 摘要：An analytical method was developed for the determination of safrole(SFL),isosafrole(DSFL) and dihydrosafrole(ISFL) in 18 foods including condiment,tomato,sauce,soy sauce,pepper,carbonated beverage,milk drink,juice,sausage,canned meat,meat soup,jelly,jam,dried fish,canned fish,fish slime,potato chip,candy and chocolate by gas chromatography-mass spectrometry(GC-MS).The sample was extracted with dichloromethane-acetonitrile in the presence of sodium chloride salt-out.Water and polar substances were removed with anhydrous sodium sulfite florisil column.For complex matrices,further purification was performed with a PRiME HLB solid phase extraction columns.The separation was carried out on a 5%phenyl-95% methyl polysiloxane capillary GC column.The detection of compounds was completed in the selected ion monitoring mode(SIM).The quantification analysis was performed by the internal standard method.Good linear relationships(r2≥0.998 1) betweeen peak areas ratios and concentrations ratios of 3 analytes were obtained in the range of 25-5 000 μg/kg.The limits of detection(LOD) for 3 analytes were 20 μg/kg.And the limits of quantitation(LOQ) were 50 μg/kg.The average recoveries of the method varied from 77.6% to 100.9% at 3 different spiked levels,with relative standard deviations(RSD) of 3.7%-13.6%.By measuring real samples,the results showed that this method was accurate and reliable for quantification and confirmation of SFL,DSFL and ISFL in foodstuffs.关键词：gas chromatography-mass spectrometry(GC-MS);selected ion monitor(SIM);solid phase extraction(SPE);safrole;spice additives;foodstuffs
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发布时间： - 摘要：The rapid quantitative detection of biochemical molecule has the advantages of simple handling，rapid detection and easy on-site analysis，thus it has a widespread application prospect in many fields such as medical diagnosis，food safety and environment monitoring.Molecular detection technology based on optical disc and optical drive can be used as the next generation molecular diagnostic tool.In this paper，a bran new quantitative detection of molecule based on bio-disc(BD) was proposed and studied around our previous research on BD detection based on CD/DVD technology.Compared with CD and DVD，Blu ray drive has a smaller focus laser size，which means higher detection throughput and sensitivity.The quantitation capability and the lateral resolution of this system were evaluated by preparing ink spot arrays with different sizes and darkness on the surface of BDs which were subsequently examined with a standard Blu-ray drive in conjunction with disc quality check software，and the Blu-ray detection system exhibits the higher sensitivity and lateral resolution（<100 μm）.In the end，biotin-streptavidin binding assay was successfully prepared on the surface of BDs，and the quantitative detection of streptavidin was achieved by a standard Blu-ray drive in conjunction with disc quality check software.关键词：Blu-ray drive/disc;quality check;sensitivity;point of care
- 1890
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发布时间： - 摘要：A method was developed for the determination of eight kinds of organochlorine pesticides，including DDTs and BHCs etc. in serum by solid-phase extraction(SPE) and gas chromatography(GC).The samples were treated by ultrasonic precipitation，cleaned on a Cleanert ODS C18 N solid phase extraction column with hexane and acetone(9∶1) and purified on a Florisil solid phase extraction column.Then，the samples were blew with nitrogen until the test tubes were dry，and resolved with N-hexane.The targeted compounds were analyzed by GC with electron capture detector(ECD) .The calibration curves were linear in the range of 2-200 ng/mL，with correlation coefficients(r) of 0.996 4-0.999 0.The limits of detection(LOD) were in the range of 0.1-0.9 ng/mL，and the limits of quantitation(LOQ) were in the range of 0.4-3.0 ng/mL.The results showed that the spiked recoveries were in the range of 80.5%-112.7% with relative standard deviations(RSD)of 2.1%-7.9%.The method has high accuracy and precision，and could be used for the analysis of trace organochlorine pesticides in serum samples.关键词：serum;DDTs;BHCs;organochlorine pesticides;solid-phase extraction(SPE);gas chromatography(GC)
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发布时间： - 摘要：An analytical method for the detection of volatile fatty acids(VFAs) was established.Acetic acid(AA)，propionic acid(PA)，butyric acid(BA)，iso-butyric acid(iso-BA)，valeric acid(VA) and iso-valeric acid(iso-VA) were chosen as the target，and a dynamic solid phase microextration(SPME) device was developed.The effects of extraction materials，extraction time，extraction temperature，extraction flow rate,extraction temperature and time of desorption were investigated on the efficiency of SPME extraction，and by which the optimal extraction conditions were determined.Furthermore，test conditions for gas chromatography were optimized,and a new dynamic SPME method was developed for gas chromatography ionization detection(GC-FID) to determine VFAs with the detection limits of 1.0-4.7 μg/L.The RSDs for three replicate extractions ranged from 1.1% to 6.8%，and the calibration curves were linear in the four orders of magnitude, with correlation coefficients(r2) more than 0.990.The developed method was successfully applied in the determination of trace VFAs in the environment.关键词：volatile fatty acids;dynamic solid-phase microextration;gas chromatography(GC);air
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- 802
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- 3
发布时间： - 摘要：Based on the enhancement of ECL intensity of Ｒu(bpy)2+3 in the presence of diuron，a new ECL method was established for the determination of diuron at the glassy carbon electrode modified with Nafion film of 3D graphene and SiO2@Ru.The 3D graphene which has the ability to enhance the intensity of electrochemiluminescence(ECL) was synthesized by a one-pot hydrothermal method.In addition，Ｒu(bpy)2+3-doped silica nanoparticle was prepared by water-in-oil microemulsion method to increase the ECL intensity.Under the optimum conditions，the ECL intensity was well proportional to the logarithmic of diuron concentration in the range of 9.08×10-11-9.08×10-7 mol/L with a detection limit as low as 1.18×10-12 mol/L.The RSD for 2.00×10-8 mol/L diuron(n=10) was 4.2%,which indicated that this method had a good repeatability.The method was applied in the determination of diuron in vegetable samples with recoveries of 99.3%-110.8%.关键词：electrochemiluminescence;diuron;3D grapheme;Ru(bpy)2+3-doped silica nanoparticle;modified electrode
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发布时间： - 摘要：A method of solvent induced phase extraction and ultra performance convergence chromatography（UPC2） was established for the determination of coumarin in Chinese traditional patent medicine and raw materials.Samples were crushed（60 mesh），and extracted with acetonitrile-water（7∶3,by volume） using dichloromethane as induced separation solvent.The targeted compound was detected by UPC2 method.The limit of detection（LOD,S/N=3） for coumarin was 0.1 mg/L.The linear range of coumarin was in the range of 0.3-10.0 mg/L.The spiked recoveries ranged from 89.8% to 102.3% and the relative standard deviations were between 0.31% and 1.0%.Compared with UPLC method，the method showed the advantages of high selectivity and low detection cost，and its analysis time is only 1/4 of the UPLC.This study provided a new pretreatment and detection method for the high throughput detection of the coumarin.关键词：coumarin;solvent induced extraction;ultra performance convergence chromatography（UPC2）;ultra performance liquid chromatography（UPLC）;detection
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- 757
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发布时间： - 摘要：A method of oligosaccharide profiling test was developed based on high performance liquid chromatography-quadrurpole/ electrostatic field orbitrap high resolution mass spectrometry(HPLC-Q/Orbitrap MS).Through qualitative and quantitative analysis of maltotriose，maltotetraose，maltopentaose，maltohexaose and maltoheptaose in pure natural honey and starch syrup，trace of malt oligosaccharides that was not totally enzymatic hydrolyzed were found in starch syrup.Furthermore，the interference of maltoheptaose in all test samples was the smallest and had no impact on the quantitative analysis results.While，the qualitative or quantitative analysis of other oligosaccharides were interfered more or less.In the analysis of real samples，the starch syrup in honey adulteration could be judged by the retention time and relative abundance ratio of maltoheptaose，therefore the content of maltoheptaose in sample solution could be quantitatively determined through standard curve method.By adding standard test，the average recoveries of maltoheptaose at three spiked levels of 20，50 and 100 mg/kg were in the range of 75%-82% with relative standard deviations(RSD，n=5) of 3.1%-6.7%.The detection limit of this method was 0.1 μg/mL.The whole analysis time could be limited in 10 min.The method had the advantages of simple processing procedure，high accuracy，reliability，sensitivity，therefore it could be applied in the rapid detection of starch syrup in honey.关键词：honey adulteration;oligosaccharide profiling test;high performance liquid chromatography-quadrurpole/electrostatic field Orbitrap high resolution mass spectrometry
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发布时间： - 摘要：To determine 18 hazardous elements including Pb,Cd,As,Hg,Cu,Sb,Sn,Cr,Ni,Ba,Mn,Tl,Ag,Be,Dy,Al,Se,Mo in 100 samples of Chinese medicinal material.The samples were prepared through microwave digestion and analyzed by inductively coupled plasma mass spectrometry(ICP-MS).The calibration curves of 18 hazardous elements were linear in the certain concentration ranges,with correlation coefficients(r) more than 0.999 5.Detection limits of the method were in the range of 0.000 22-0.023 0 mg/kg.The recoveries were in the range of 90.2%-108.7% with RSDs of 1.8%-4.9%.The method is highly sensitive,rapid and accurate,and could provide a reference for determination of hazardous elements in Chinese medicinal material.关键词：Chinese medicinal material;heavy metal and hazardous elements;inductively coupled plasma mass spectrometry(ICP-MS)
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发布时间： - 摘要：A liquid chromatography-inductively coupled plasma mass spectrometric(LC-ICP-MS) method was established for the determination of chromium(Ⅵ) and chromium(Ⅲ) stripped from stopcock.By investigating pH value,ICP-MS operation conditions and parameters,the detection limits of chromium(Ⅵ) and chromium(Ⅲ) were obtained to be 0.013 μg/L and 0.028 μg/L，respectively.Linear ranges of chromium(Ⅵ) and chromium(Ⅲ) were 0.02-10 μg/L and 0.04-20 μg/L，respectively.The spiked recoveries varied from 76.0% to 116.4%,with RSDs of 1.8%-2.8%.The method is fast and accurate,and has a low detection limit.It is suitable for the detection requirement of stopcock products.关键词：liquid chromatography-inductively coupled plasma mass spectrometry(LC-ICP-MS);stopcock;chromium(Ⅵ);chromium(Ⅲ)
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发布时间： - 摘要：A method was explored for the preparation of affinity chromatographic support， based on the hydrophilic gigaporous polymer microspheres using Protein A as affinity ligands.The effect of H5IO6 on amount of Protein A was evaluated.The morphology of the microspheres was observed by scanning electronic microscopy.The result showed that the throughput pores were maintained in the affinity media.At different flow rates(361-3 600 cm/h)，the dynamic capacity of human Ig G on the affinity supports were determined,and the result indicated the capacity at 3 600 cm/h decreased about 10% in comparison with that at 361 cm/h.The above results indicated that this affinity support could meet the requirement for rapid and high-throughput separation of proteins.关键词：affinity chromatography;coupling method;Protein A ligand;gigaporous chromatographic support;purification of antibody
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发布时间： - 摘要：Surface enhanced Raman spectroscopy(SERS) technique has attracted the attention from analysts due to its advantage of potential capability for on-site rapid analysis and so on.However，the SERS signals would be easily influenced by the complex sample matrixes during real analytical processes，acquiring poor reproducibility.Thus，SERS technique is mostly used in qualitative or semi-quantitative analysis projects at present，and reliable SERS quantitative analysis technique still remains to be improved.With the continuous development of science and technology，an increased demand of people for more accurate surface enhanced Raman quantitative techniques is developed.Herein，the research progress of currently popular SERS quantitative analysis techniques is reviewed，including external standard methods，internal standard methods and chemometrics quantitative methods，in recent years.In addition，the development trend of SERS quantitative analysis technology is prospected in the future.关键词：surface enhanced Raman spectroscopy(SERS);quantitative analysis technology;research progress;review
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发布时间： - 摘要：Microwave induced combustion(MIC),as a kind of microwave assisted environmentally friendly sample pretreatment method,has particularly attracted much interest in recent years.The internal instructure and application procedures of the MIC reactor help to burn completely and improve the recoveries of the elements.The combustion reaction between sample and oxygen goes rapidly under the microwave irradiation in the presence of igniter.After the reaction,elements are absorbed by the absorbing solution through refluxing process.To determine elemental type and speciation as well as their contents,the absorbing solution may be analyzed by the element analytical instruments,such as AAS,ICP-OES,ICP-MS and IC,etc.This environmentally friendly method could be applied in a wide range of samples with short combustion time,low residual carbon content,high recovery of elements and low loss of volatile elements,which will remain as a research focus of the sample pretreatment in the following decades.In this paper,the basic principle,reaction system,igniter and absorbing solution,sample preparation of MIC and its applications in the field of food,biology,polymer,geology,coal,crude oil and carbon material are introduced,which could provide more effective and significant reference value for the studies in the future.关键词：microwave induced combustion(MIC);microwave reactor;sample pretreatment;element analysis;review
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