最新刊期
卷 36 ， 期 7 ， 2017
- 摘要：The volatile compositions of the Agarwoods from different production places were extracted by solid phase microextraction(SPME),and isolated and identified by GC-MS,then the quality of Agarwood was evaluated.The investigation showed that the Agarwoods from different places were all consisted of sesquiterpenoids and aromatic compounds,but their chemical compositions and contents were quite different.The six characteristic components,including 4-phenyl-2-butanone, p-methoxybenzylacetone, agarospirol,agarofuran,hinesol and baimuxinal,and their contents were used as the evaluation indexes for the quality of the Agarwoods. The results indicated that the contents of characteristic constituents in Laos Agarwood were the highest(about 20%),the contents in the Cambodian Agarwood were the second(17%),while the contents in the Chinese Agarwoods(Hainan and Dongguan) were the lowest. Therefore,the Laos Agarwood had the best quality,the Cambodian Agarwood was slightly poorer, and they both were superior to the Chinese Agarwood. The method showed the advantages of low sample consumption and strong characteristic.关键词：agarwood;solid phase microextraction(SPME);GC-MS;characteristic constituents;different places of production
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发布时间： - 摘要：A method for the determination of 122 pesticide residues in fruits and vegetables from the Hong Kong’s regulation was developed by QuEChERS combined with ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). The quantification and confirmation was achieved by electrospray ionization(ESI) in positive and negative ion mode using multiple reaction monitoring(MRM) mode, and the analytes were quantified by the external standard method. The standard curves of 122 target compounds were linear in the range of 0.010-0.20mg/L,with correlation coefficients(r) not less than 0.99.The limits of quantitation(LOQ) were 0.010mg/kg. The recoveries at three spiked levels were in the range of 60%-110% with RSDs of 1.8% and 19.4%.The method had the advantages of rapidness,simplicity,time-saving,high sensitivity and good stability, and could significantly reduce the test cost.关键词：QuEChERS;ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS);pesticide residues
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发布时间： - 摘要：A dispersive solid phase extraction(d-SPE) purification coupled with liquid chromatography tandem mass spectrometric(LC-MS/MS) method was developed for the simultaneous determination of seven aminoanisoles including 2-anisidine(2-ANI),3-anisidine(3-ANI),4-anisidine(4-ANI),2,4-diaminoanisole(2,4-DANI),2,5-diaminoanisole(2,5-DANI),3,4-diaminoanisole(3,4-DANI) and 3,3′-dimethoxybenzidine(3,3′-DMBD) in cosmetics. The samples were extracted with methanol aqueous solution containing 0-1% formic acid, and purified by a simple d-SPE employing PSA as adsorbents. The target analytes were separated on a Welch Ultimate XB-C18 chromatographic column(4.6mm×150mm,5μm) and subsequently detected through an electrospray ionization(ESI) source in the positive mode under multi-reaction monitoring(MRM) conditions. An external standard method was adopted for the quantification. Under the optimized conditions,the callibration curves of seven analytes were linear in the concentration range of 0.10-200.0μg/L, with correlation coefficients(r2) greater than 0.998.The limits of detections(LODs) were in the range of 0.4-10.9μg/kg. The average recoveries were calculated to be between 64.7% and 98.1%, with relative standard deviations(RSDs) of 1.2%-10.6% for intra-day precision(n=6) and 2.3%-9.8% for inter-day precision(n=5).The method was successfully applied in the determination of aminoanisole contents in thirty complex cosmetics samples, and 3,3′-dimethoxybenzidine(3,3′-DMBD) was detected in one sample with a content of 5.3μg/kg. The method is accurate and reliable, and could be used for the simultaneous determination of 7 aminoanisoles in cosmetics.关键词：liquid chromatography tandem mass spectrometry(LC-MS/MS);dispersive solid phase extraction(d-SPE);cosmetics;aminoanisole
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发布时间： - 摘要：In this paper,graphene(rGO) was immobilized on the surface of the electrode by the method of electrochemical reduction of graphene oxide(GO),and then the copper hydroxide-nickel hydroxide nanocomposites were electrodeposited to form graphene/metal hydroxide nanocomposites modified glassy carbon electrode(GCE/rGO/Cu(OH)2-Ni(OH)2).Finally,horseradish peroxidase(HRP) was immobilized onto the surface of the above prepared electrode by electropolymerizing azure I to form the GCE/rGO/Cu(OH)2-Ni(OH)2/HRP-PA(PA: poly azure Ⅰ).The graphene/metal hydroxide nanocomposites were characterized by SEM and EDS.The preparation process and electrochemical performance of the sensor were investigated by electrochemical impedance spectroscopy and cyclic voltammetry.Hydrogen peroxide tert-butyl(BHP) and cumene hydroperoxide(CHP) were determined by the sensor.The linear response of the HRP sensor to BHP was in the concentration range of 2.0×10-5-9.2×10-4mol/L with a detective limit of 9.9×10-6mol/L and that to CHP was in the concentration range of 3.0×10-6-1.0×10-4mol/L with a detective limit of 6.9×10-7mol/L.关键词：graphene;metal hydroxides;azure I;organic peroxide;HRP sensor
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发布时间： - 摘要：A headspace gas chromatographic(HS/GC) method was established for the determination of volatile benzene and benzene homologues in eraser.The sample pretreatment and chromatographic conditions were optimized.After properly crushed,the sample was detected by HS/GC,and the result showed that this method had the advantages of saving solvent,environment friendliness,rapidness and simplicity.The linear ranges of 8 volatile benzene and its homologues were in the range of 0.05-5.00μg/g,with correlation coefficients more than 0.999.The detection limits were in the range of 0.02-0.04μg/g,and the average recoveries were in the range of 91.9%-98.9% with the relative standard deviations less than 5%.Market monitoring analysis showed that the contents of the volatile benzene and its homologues in different brands and different kinds of erasers were quite different.And it was still imperative to increase the safety supervision on this kind of products though the market was relatively safe.关键词：headspace/gas chromatography(HS/GC);eraser;benzene and benzene homologues
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发布时间： - 摘要：An ultra performance liquid chromatography-tandem mass spectrometric（UPLC-MS/MS） method was developed for the rapid determination of 5 artificial sweeteners,6 iodinated X-ray contrast agents and caffeinein in various water samples（surface water,inflow and effluent for wastewater treatment plant）. The filtered water samples were extracted,and purified through HR-X solid phase extraction cartridges and separated on a Zorbax SB-C18 column. The determination of analytes was performed under multiple reaction monitoring（MRM） mode using acetonitrile-water（10 mmol/L ammonium acetate,0.01% formic acid） and acetonitrile-water（5 mmol/L ammonium acetate,1 mmol/L Tris） as mobile phases in positive ionization mode and negative ionization mode,respectively. The calibration curves of the target compounds were linear in the range of 5-5 000 μg/L with correlation coefficients more than 0.998. The recoveries of the target compounds in surface water,inflow and effluent were all between 70% and 120%,with relative standard deviations（RSD） of 0.8%-19.0%. The method detection limits（MDL） for three types of water samples were in the ranges of 0.43-13.8 ng/L,1.80 -34.8 ng/L and 2.30-134 ng/L,respectively. The method was successfully applied in the determination of artificial sweeteners,iodinated X-ray contrast agents and caffeine in different actual water samples collected from a wastewater treatment plant and its receiving river from Guangzhou city. Except for aspartame,iothalamic acid,iopromide and iomeprol,the other compounds were all detected with high concentrations. The established method is accurate,sensitive and simple,and is suitable for the determination of artificial sweeteners,iodinated X-ray contrast agents and caffeine in various environmental water samples.关键词：artificial sweeteners;iodinated X ray contrast agents;caffeine;ultra performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）;water samples
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发布时间： - 摘要：An ultra performance liquid chromatography-tandem mass spectrometric(UPLC-MS/MS) method was developed for the simultaneous determination of 5 fusarium mycotoxins in wheat flour,including enniatins A,enniatins A1,enniatins B,enniatins B1 and beauvericin.The fusarium mycotoxins were extracted from the samples using a modified QuEChERS-based extraction procedure without any further clean-up step.The separation of the analytes was carried out on an Agilent Eclipse Plus C18 column(50 mm×2.1 mm,1.8 μm) using the mobile phases of methanol and 2 mmol/L ammonium acetate by gradient elution．The detection was performed in the electrospray ion(ESI) positive mode and multiple reaction monitoring(MRM) mode.The matrix-matched calibrations were used to quantify the residue concentrations.The proposed method showed good linear relationship with correlation coefficients all above 0.993.The limits of detection(LODs)were in the range of 0.3-0.8 μg/kg,and the limits of quantitation(LOQs) were 0.8-2.4 μg/kg.The blank samples were fortified at three spiked levels(1 times,2 times,10 times of LOQ),and the average recoveries ranged from 74.0% to 85.4% with relative standard deviations(RSDs) of 5.6%-13.1%.The developed method was successfully applied in analysis of fusarium mycotoxins in 30 samples bought from the market.The method was simple,rapid,accurate and sensitive,and was suitable for the simultaneous analysis of multi-fusarium mycotoxins in wheat flour.
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发布时间： - 摘要：A potentiometric method was developed for the determination of salbutamol sulfate by using a novel carbon coated polyvinyl chloride membrane salbutamol sulfate selective electrode modified with nano-Fe2O3.The prepared electrode showed a good Nernst response in the linear range of 1.0×10-6-0.1 mol/L with a slope of 59 mV/pC.Compared to the unmodified electrode，the electrode modified with nano-Fe2O3 exhibited a faster response time(10 s) and a lower detection limit(2.8×10-7 mol/L).The modified electrode was applied in the determination of salbutamol sulfate in pork samples， and the results were in agreement with those obtained by the standard method.关键词：nano-Fe2O3;salbutamol sulfate;determination;electrode;pork
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发布时间： - 摘要：The samples of toys paint coating for the proficiency testing program(PT) “determination of migration Organic Tin in toys paint coating”were prepared,and applied in a PT scheme. 23 labs data were counted and analyzed by iterative method，quartile method and sensitivity analysis method. The cause of unsatisfactory results was also analyzed in this report. The results showed that PT samples had good homogeneity and stability，which could meet the requirement of this PT. Different statistical methods might lead to different assessment results for the laboratories. As the difference of assigned value was very small，but the difference of standard deviation for proficiency assessment was relatively larger. A more reasonable statistical method was selected by using chi-square-goodness of fit test.关键词：toy;migration organic tin;proficiency testing;statistic analyse
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发布时间： - 摘要：A method for the determination of malachite green(MG)，crystal violet(CV) and their metabolites residues leucomalachite green(LMG) and leucocrystal violet(LCV) in aquatic product was developed using QuEChERS combined with UPLC-MS-MS.The sample was extracted with acetonitrile and purified by EMR-Lipid.The target compounds were separated on an Agilent Eclipse Plus C18(1.8 μm,3.0 mm×100 mm) column,and detected by tandem mass spectrometry with electrospray ionization in positive mode.The linear ranges were in the range of 0.2-10.0 μg/L and the correlation coefficients were all above 0.997．The average recoveries of 4 analytes in fish matrix at three spiked concentrations of 0.5，1.0，5.0 μg/kg ranged from 77.1% to 106.6%,with relative standard deviations of 1.3%-4.3%．This method was simple and reliable，and could effectively remove the protein and fat in sample.Therefore,it is suitable for the determination of MG,CV and their leuco metabolites residues in aquatic product.关键词：QuEChERS;EMR-Lipid;UPLC-MS-MS;malachite green(MG);leucomalachite green(LMG);crystal violet(CV);leucocrystal violet(LCV)
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发布时间： - 摘要：A rapid method combining molecularly imprinted polymers with surface enhanced Raman spectroscopy(MIPs–SERS) was established for the determination of theophyline illegally added into traditional Chinese Medicine.MIPs were synthesized by precipitation polymerization,and the theophylline was simply separated from the complex traditional Chinese medicine(TCM) substrates, then detected qualitatively by SERS.The structures of the newly synthesized MIPs were characterized by Fourier transmission infrared spectrometry(FT-IR) and scanning electron microscopy(SEM).The thermodynamics and kinetics and selective adsorption capacity of the MIPs，as well as the limit of detection for adulteration were also investigated.The results showed that MIPs had a better specificity and selectivity than NIPs，and the limit of detection was as low as 1 μg/L.Five kinds of real TCM relieving cough and asthma were tested，and one sample was detected to have theophylline components added illegally. With the advantages of high sensitivity，strong specificity，no pretreatment，simplicity and rapidness,the method could be used for the rapid detection of theophylline illegally added in TCM and further applied in other complicated matrix system.关键词：molecularly imprinted technology;surface enhanced Raman spectroscopy;traditional Chinese medicine(TCM) adulteration;theophylline
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发布时间： - 摘要：A high performance liquid chromatography-quadrupole ion trap tandem mass spectrometric(HPLC-QTRAP-MS/MS) method was developed for the quantification of 1-(2-hydroxyethyl) piperidine residue in flavoxate hydrochloride.After dissolved with 0.1% formic acid,the flavoxate hydrochloride sample was loaded onto an Agilent ZORBAX SB-Aq C18(2.1 mm×100 mm，1.8 μm) column to separate with a mobile phase of 0.1% formic acid-acetonitrile.The electrospray was operated in positive ion mode,and the sample was monitored in the select reaction monitoring(SRM) mode.As a result,the calibration curve of 1-(2-hydroxyethyl)piperidine showed a good linearity(r=0.999 7) in the range of 10-100 μg/L.The recoveries were in the range of 98.9%-106.8%,with relative standard deviations(RSDs) not more than 3.0%.The limit of detection(LOD,S/N=3) for the method was 6.0 mg/L,and the limit of quantitation(LOQ,S/N=10) was 20 mg/L.The method has the advantages of simple operation,high sensitivity and good reproducibility,and could be used for the detection of 1-(2-hydroxyethyl)piperidine in flavoxate hydrochloride.关键词：high performance liquid chromatography-quadrupole ion trap tandem mass spectrometry(HPLC-QTRAP-MS/MS);flavoxate hydrochloride;1-(2-hydroxyethyl)piperidine
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发布时间： - 摘要：A method was developed for the simultaneous determination of 15 phenoxyacid herbicides in tobacco.Samples were extracted with acetonitrile(MeCN),then cleaned up with TPT SPE column.The methylation of analyte was performed with trimethylsily-diazmethan,and the detection was carried out by gas chromatography-tandem mass spectrometry(GC-MS/MS).The method showed a good linearity over the concentration range of 20-1 000 μg/L with correlation coefficients all above 0.992.The limits of detection and quantitation were 0.9-3.3 μg/kg and 3.2-10.8 μg/kg,respectively.The average recoveries of analytes at three fortified levels(20,100,200 μg/kg) were in the range of 71.5%-105.6%,with RSDs of 4.5%-14.9%.The proposed method is simple,rapid and sensitive,and is suitable for the simultaneous determination of 15 phenoxyacid herbicides in tobacco.关键词：tobacco;phenoxyacid herbicides;gas chromatography-tandem mass spectrometry(GC-MS/MS);solid phase extraction(SPE);methylation
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发布时间： - 摘要：By optimizing the chromatographic column，further improving the chromatographic separation condition and optimizing the pretreatment method，a rapid and efficient method was established for the determination of 27 kinds of semi volatile organic pollutants（SVOCs） in groundwater by GC-MS. The outstanding features of this method are the variety of analytes，rapid processing，low solvent consumption，low environmental pollution and short chromatographic run time. The method could keep stable for 40 min，and is suitable for the detection of large quantities of samples. In addition，the standard curve was prepared using the matrix matched standard solution，which lead to the matrix effect reduced，and the application of the ion（SIM） scanning could obtain a high sensitivity. The detection limits of the method are in the range of 0.000 4-0.013 μg/L,and the spiked recoveries are 70.5%-92.8% with RSD（n=6） not more than 11.2%.关键词：SVOCs;GC-MS;matrix effect;simultaneous determination;batch processing
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发布时间： - 摘要：A novel electrochemical sensor for the determination of ribavirin(RIB) was fabricated by molecularly imprinted technology，based on 3-aminobenzeneboronic acid as functional monomer，and ribavirin as target molecule.A molecularly imprinted polymers（MIPs） membrane was synthesized on the surface of glassy carbon electrode in vacuum drying oven，by the formation principle of ring ester bond with boric acid and vicinal diol.The electrochemical behavior of the membrane was characterized by cyclic voltammetry(CV) and differential pulse voltammetry(DPV).Under the optimum conditions，the response of peak currents was linear to concentration of RIB in the range of 5.0×10-8-1.0×10-5 mol/L with a detection limit(S/N=3) of 1.5×10-8 mol/L.The electrochemical sensor has the advantages of high sensitivity，good stability and high reproducibility，and could be uesd to detect RIB in food.关键词：ribavirin(RIB);in-situ polymerization;molecular imprinting polymer (MIP);electrochemical sensor
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发布时间： - 摘要：A new method was established to determine 2-bromo-2-nitro-1，3-propanediol in cosmetics by high performance liquid chromatography-inductively coupled plasma mass spectrometry(HPLC-ICP-MS). The analyte was separated on a ZORBAX-C8 column (150×2.1 mm， 5 μm) using methanol-water-5% phosphoric acid (10 ∶ 985 ∶ 5， pH value was adjusted to 3.0 with 2 mol/L NaOH) as mobile phase. The flow rate was set at 0.7 mL/min. The column temperature was room temperature. The results indicated that the calibration curve of 2-bromo-2-nitro-1，3-propanediol was linear in the range of 0.01-1.0 mg/L，with a correlation coefficient(r) of 0.999 9. The detection limits of different matrix samples were all 1.0 μg/g. The spiked recoveries of 2-bromo-2-nitro-1，3-propanediol ranged from 94.6% to 101.3%， with RSDs(n=6) of 1.5%- 4.5%. The method showed the advantages of rapidness，sensitivity，accuracy and little interference，and it could be used for the qualitative and quantitative determination of 2-bromo-2-nitro-1，3-propanediol in cosmetics.关键词：high performance liquid chromatography(HPLC);inductively coupled plasma mass spectrometry(ICP-MS);2-bromo-2-nitro-1,3-propanediol;cosmetics
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发布时间： - 摘要：A high performance liquid chromatography -mass spectrometric(HPLC-MS) method was developed for the determination of hexabromocyclododecanes (HBCDDs, including alpha, beta, gamma, three isomers) in electrical and electronic products, by optimization of ultrasonic extraction time, extraction cycle and extraction solvent.In the optimal conditions,the sample was ultrasonically extracted with toluene for three times and each took 15 min.The extracts were combined and concentrated to dryness under nitrogen, then redissolved with methanol water solution.The calibration curves of HBCDDs were linear in the range of 50-5 000 μg/L, with correlation coefficients more than 0.999.The detection limits were all 1 mg/kg.The spiked recoveries were in the range of 88.3%－104.5%.The method was proved to be quick,simple,accurate and stable.It was successfully applied in the determination of HBCDDs in real samples, of which the detected samples were polystyrene关键词：electrical and electronic products;hexabromocyclododecanes(HBCDDs);ultrasonic extraction;high performance liquid chromatography -mass spectrometry(HPLC-MS)
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发布时间： - 摘要：A high accuracy method of qNMR with inverse gated decoupling technique was established to determine the content of phenylethanolamine A.Considering the choice of deuterated solvents,internal standards and quantitative peaks,and the optimization of relaxation delay,aquisition number and temperature,the final measurement conditions of qNMR spectra were as follows:flip angle:30°,date point:32 K,detection temperature:293 K,a relaxation delay:33.64 s,acquisition times:64 times,line broadening:0.3 Hz.The experimental results showed that the stability of this condition could be maintained for 24 h.A good linear relationship was obtained between peak area ratio and molar ratio in the range of 0.333-3.333,and the correlation coefficient (r2) was 0.999 9.The established method is specific,accurate and simple,and could be used for the content determination of this kind of compounds.关键词：phenylethanolamine A;qNMR;inverse gated decoupling;purity
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发布时间： - 摘要：A fluorescent probe with high selectivity and sensitivity was synthesized for hydrazine determination in physioligical condition(pH 7.4) based on coumarin dyes.Structure of the probe was characterized by nuclear magnetic resonnce and high resolution mass spectrometry.A strong fluorescence imine coumarin was generated by using hydrazine attacking 4-butyrate to release phenolic oxygen anion and produce molecular inner reaction.With the addition of hydrazine(0-100 μmol/L)，the fluorescence intensity of the probe displayed a remarked enhancement(55 fold) in green spectral region(502 nm).The probe could be used to detect low concentration of hydrazine，with a detection limit of 1.7×10-7 mol/L.Compared with the other anions and nuclear reagents，this probe showed higher selectivity and sensitivity to recognize hydrazine.More importantly，the probe was successfully implemented to detect hydrazine in living cells，which proved that the hydrazine fluorescent probe has a potential capability in cell imaging.关键词：fluorescence imaging;synthesis;coumarin;fluorescence probe;hydrazine
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发布时间： - 摘要：More and more attention has been paid to the security of dairy products in recent years.Veterinary drug residue is an important part of chemical hazards so that the research on detection technology has always been a hotpot of dairy products safety analysis.Liquid chromatography-mass spectrometry(LC-MS) has become a mainstream in veterinary drug residues analysis because of its special advantages of sensitivity and selectivity.The veterinary drug residues analysis based on LC-MS has been developed into multiclass and multiresidue stages gradually.While the differences of physicochemical properties,residual station and limited quantity exist among the multiclass veterinary drugs,both the sample pretreatment and subsequent instrument analysis have come across certain technological difficulties.To know more about the research development in this field,the literatures concerning the multiresidue determination of veterinary drugs in dairy products using LC-MS at home and abroad in resent years are summarized in this paper,from several aspects including sample pretreatment,LC-MS detection and matrix effect.关键词：dairy products;veterinary drugs multi residue;liquid chromatography-mass spectrometry(LC-MS);research progress
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