最新刊期
卷 38 ， 期 9 ， 2019
- 摘要：In order to construct a new non enzymatic electrochemical biosensor and use it for the effective detection of the release of H2O2 from cells,the graphene oxide(GO) modified by polydiallyl dimethyl ammonium chloride(PAC) and nano Pt were immobilized on glass carbon electrode(GCE) through the physical adsorption and electrodeposition of H2PtCl6 solution,respectively,and a Pt/PAC-GO/GCE electrochemical biosensor was successfully prepared.Through the characterization of scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS),it was observed that the electrodeposited nano Pt were densely covered and well distributed on the PAC-GO surface.Under the optimal experimental conditions,the Pt/PAC-GO/GCE biosensor exhibited a high peak current toward H2O2 and wide linear ranges for H2O2 in the range of 0.04-3.6 μmol/L and 4.4-28.6 μmol/L,with a detection limit of 0.01 μmol/L.Moreover,the Pt/PAC-GO/GCE biosensor exhibited excellent anti-interference capability and reproducibility for the detection of H2O2,and was also successfully used in the detection of H2O2 in different living cell.All these results proved that the prepared biosensor has a potential application in clinical diagnostics.关键词：biosensor;H2O2;nano Pt;graphene oxide(GO)
- 1268
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发布时间： - 摘要：A QuEChERS/high performance liquid chromatography-tandem mass spectrometric(HPLC-MS/MS)method was developed for the determination of 61 kinds of hormone residues in soil.Samples were extracted with acetonitrile,and then purified using QuEChERS method.Analysis on the targets was performed by electrospray ionization mass spectrometry in positive or negative mode,multiple reaction monitoring(MRM) mode was used for collection,and matrix matched standard curve method was selected for quantitation.Results showed that 61 analytes showed good linearities in their respective ranges,with correlation coefficients(r2) between 0.991 8 and 0.999 8.The limits of detection(LOD,S/N≥3) were 0.01-2.3 μg/kg while the limits of quantitation(LOQ,S/N≥10) were 0.03-7.5 μg/kg.Recoveries for the target analytes at spiked levels of 10,50 and 200 μg/kg ranged from 62.6% to 102%,with relative standard deviations(n=6) of 1.0%-11%.The method is simple,rapid,replicable and high stable,and could meet the requirements for determination of 61 hormone residues in soil.关键词：high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS);QuEChERS;hormone residues;soil
- 1324
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发布时间： - 摘要：The near infrared quantitative model established through the small test preparation process is difficult to apply in the pilot or large scale production process directly,which discourage the development of near infrared spectroscopy in the pharmaceutical preparation process.To solve this problem,the fluidized bed granulation process with medicinal dextrin was adopted in this paper.Meanwhile,the NIR spectrum data and the moisture contents of samples in the above preparation process experienced both the small test and the pilot test were collected.Then the near infrared quantitative model for moisture content was established with 3 batches of samples in small test.Based on this,a model transfer method,directed direct orthogonal signal correction combined with slope/bias correction(DDOSC-SBC) was proposed to predict the moisture content of pilot samples.The relative standard errors of prediction for two separate pilot test sets were decreased from 51.04% and 26.64% to 4.90% and 3.99%,respectively after using this directed model-transfer method.Compared with undirected direct orthogonal projection technique combined with slope/bias correction(DOSC-SBC) and the model update,this method could remove the interference spectrum information from pilot test samples more effectively.Consequently,this method provides a new idea for application of the near infrared quantitative model transitting from small test to pilot test or even expanding to the large scale production process.关键词：near infrared quantitative model;fluidized bed granulation;model transfer;directed direct orthogonal signal correction;slope-bias correction method
- 1258
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发布时间： - 摘要：A “light-up” fluorescence method was developed for the quantitative analysis of kanamycin based on DNA template synthesized silver nanoclusters(AgNCs).The silver nanoclusters with weak fluorescence were synthesized with DNA as template.A hairpin structure was formed to make the G and C bases in the aptamer sequence of DNA template close to the silver nanoclusters when the target kanamycin was identified by the aptamer sequence,which could result in the increase of fluorescence of silver clusters.Meanwhile,the change of secondary structure caused the silver nanoparticles to transform into smaller silver nanoclusters,which also enhanced the fluorescence of silver clusters.A “light-up” fluorescence method was established based on this mechanism.There was a linear relationship between fluorescence intensity ratio of silver nanoclusters and kanamycin in the concentration range of 0.075-8.0 μmol/L with a calibration curve of F/F0 =0.616 8C+0.927 6,and a detection limit of 36 nmol/L.The spiked recoveries for kanamycin in milk and honey samples ranged from 92.4% to 112%.In addition,with the increase of kanamycin concentration,the orange fluorescence of silver nanoclusters was deepened gradually,which could be used for the visual semi-quantitative detection of kanamycin.With good sensitivity and selectivity,the method could be used in the quantitative determination of trace kanamycin in complex food samples.关键词：DNA template;silver nanoclusters(AgNCs);kanamycin;visual detection
- 1258
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发布时间： - 摘要：A high performance liquid chromatography-tandem mass spectrometric(HPLC-MS/MS) method was developed for the rapid determination of six anesthetics,eg.procaine,lidocaine,bupivacaine,tetracaine,tricaine methanesulfonate(MS-222) and benzocaine in aquatic products.The samples were extracted with water and acetonitrile containing 1.0% formic acid,and then cleaned up with a PRiME HLB pass through solid phase extraction column.The targets were separated on a ZORBAX Eclipse XDB-C18 column(3.0 mm×150 mm，3.5 μm) with acetonitrile-0.1% formic acid as mobile phase by gradient elution.The analytes were determined in electrospray positive ionization(ESI+) mode under multiple reaction monitoring(MRM).Results showed that there were good linear relationships for the targets in their respective concentration ranges with correlation coefficients(r2) of 0.993 8-0.998 7.The limits of detection(LOD) and limits of quantitation(LOQ) were in the ranges of 1.5-6.0 μg/kg and 5.0-20 μg/kg,respectively.Average spiked recoveries for six anesthetics were in the range of 76.8%-110% with relative standard deviations of 4.2%-11%.The proposed method is simple,quick,accurate and sensitive,and is suitable for the determination of six anesthetics in aquatic products.关键词：anesthetics;pass-through solid phase extraction;aquatic products;high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)
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发布时间： - 摘要：In order to systemically make sure and quantify the diefary intake of pesticide residues in peaches,98 peach samples from 19 main producing areas in China were detected.Chronic or acute dietary intake risk of pesticide residues in these samples were assessed by ADI and ARfD,respectively,and the Matrix Ranking developed by the Veterinary Residues Committee of the United Kingdom was referred to rank the risk of pesticides and peach samples.Results showed that 38 pesticides in 98 peach samples were detected with a detection rate of 95.9% and pesticides contents of 0.007 4-3.399 3 mg/kg.Only 4 peach samples contained residues above the MRLs.For 38 pesticides with detectable residues,their %ADI and %ARfD averages were 0.89% and 11.9%,respectively,far below 100%,indicating that there existed very little risk for these pesticide residues in peaches to human health.The pesticides in peach samples ranked by risk index showed that fipronil,endosulfan,methomyl,carbosulfan,chlorpyrifos and bifenthrin had high pesticide residue risk which should be focused on in the production and the quality and safety supervision.This study provides a scientific basis for peach consumption,peach pesticide residue supervision and establishment of maximum residue limits(MRLs) for pesticides in peach.关键词：peach;pesticide residue;risk assessment;maximum residue limit
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发布时间： - 摘要：A water stable metal-organic framework MIL-101(Fe) was synthesized by the solvothermal method,which could be employed as a high efficiency adsorbent for removal of microcystin-LR in aqueous solution.The as prepared nanomaterial was characterized by Electron microscopy,Fourier transformed infrared(FT-IR),zeta potential and N2 adsorption desorption measurement,respectively.The MIL-101(Fe) had a porous structure and a high specific surface area(375.2 m2/g) with an average size about 500 nm.Experimental parameters affecting the adsorption capacity,including pH,ionic strength and temperature,adsorption time and concentration were particularly optimized.Results indicated that the adsorption mechanisms could be expressed by the electrostatic attraction and coordination interaction between MIL-101(Fe) and microcystin-LR.The adsorption of microcystin-LR on MIL-101(Fe) was very fast as an adsorption equilibrium was obtained within 20 min,which agreed well with the pseudo second order model.Moreover,the porous MIL-101(Fe) exhibited an excellent adsorption property for microcystin-LR,with a maximum adsorption capacity of 256.4 mg/g.The humic acid in the solution could affect the adsorption capacity of MIL-101(Fe).Under the same conditions,the adsorption capacity for microcystin-LR in river water decreased due to the influence of humic acid and salts in real water samples.Nevertherless,the adsorption capacity still reached to 68.1 mg/g.Thus,the method is efficient and convenient,and is suitable for the rapid removal of microcystin-LR in contaminated water.关键词：metal-organic frameworks;adsorption;microcystin;MIL-101(Fe)
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发布时间： - 摘要：A low temperature plasma ionization mass spectrometry with a thermal desorption device was developed for the direct and rapid screening of 8 organophosphorus pesticides in vegetables.The vegetable sample was extracted with acetonitrile,and the supernatant was analyzed by mass spectrometry after centrifugation.In the positive ion detection mode,the sample was placed on a heating block for desorption,ionized with a low temperature plasma,and then subjected to mass spectrometry.Results showed that there were good linear relationships for the 8 analytes in range of 0.005-0.200 mg/L with their correlation coefficients greater than 0.99.The detection limits were in the range of 0.001-0.010 mg/L.The recoveries for Chinese cabbage ranged from 90.5% to 119% with relative standard deviations(RSDs,n=6) of 12%-17%.The detection sensitivity was improved by 9.3 to 41.7 times compared with that without thermal desorption.With simple operation,easy pretreatment,high sensitivity and good accuracy,the method could be applied in the simultaneous determination of pesticide residues in vegetables,and has a great application prospect in non targeted analysis for large batch of samples.
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发布时间： - 摘要：A high performance liquid chromatography-(ultraviolet) hydride generation-atomic fluorescence spectrometric(HPLC-(UV)HG-AFS) method was developed for the determination of six arsenic speciations in Antarctic krill(Euphausia superba) and its products.Various instrumental conditions such as concentration and pH value of mobile phase,negative high pressure,pump speed and pretreatment conditions were optimized.Under the optimal conditions,there were good linear relationships for arsenious acid(As(Ⅲ)),arsenic acid(As(V)),monomethylarsenic acid(MMA),dimethylarsenic acid(DMA),arsenic betaine(AsB) and arsenic choline(AsC) in the range of 5-100 μg/L with correlation coefficients(r2) larger than 0.999 0.The limits of detection(LOD，S/N≥3) and quantitation(LOQ，S/N≥10) were 0.01 mg/kg and 0.03 mg/kg，respectively.Average recoveries at three spiked levels of 0.01,0.05 and 0.10 mg/kg were in the range of 89.2%-108% with relative standard deviations(RSD,n=6) of 3.4%-14%．The proposed method was successfully applied in the determination of six arsenic speciations in Antarctic krill and its products.The contents of inorganic arsenic speciations(As(Ⅲ) and As(Ⅴ)) were lower than those of the national limit standard for aquatic products and their products.The developed method is simple,wide ranging,accurate and reliable,and could be applied in the speciation analysis of arsenic in Antarctic krill and its products.关键词：arsenic speciation;Antarctic krill;high performance liquid chromatography-(ultraviolet) hydride generation-atomic fluorescence spectrometry
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发布时间： - 摘要：A method was established for the determination of 11 marine biotoxins in seafood by high performance liquid chromatography-quadrupole electrostatic field orbitrap high resolution mass spectrometry(HPLC-Q-Orbitrap HRMS).It was a one stop extraction and purification system for hydrophilic and lipophilic marine biotoxins.Samples were firstly treated by sequential extraction procedure,then cleaned up by disperse solid phase extraction(dSPE) combined with carrier assisted liquid-liquid extraction(SLLE).Under the optimal conditions,the calibration curves for 11 marine biotoxins were linear in the certain concentration ranges,with correlation coefficients greater than 0.99.The limits of detection(LOD) and limits of quantitation(LOQ) were in the ranges of 1-10 μg/kg and 2-20 μg/kg,respectively.The spiked recoveries ranged from 55.6% to 122% with relative standard deviations(RSD) of 5.4%-16%.The method was simple,efficient and operable,and could solve the problem of high throughput detection of hydrophilic and lipophilic marine biotoxins in seafood and meet the requirements for rapid screening.关键词：marine biotoxins;dispersed solid phase extraction(dSPE);carrier assisted liquid-liquid extraction(SLLE);high-performance liquid chromatography-quadrupole electrostatic field orbitrap high resolution mass spectrometry(HPLC-Q-Orbitrap HRMS)
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发布时间： - 摘要：A method was developed for the analysis of unkwown compositions in a metal processing additive by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) combined with nuclear magnetic resonance(NMR),infrared spectroscopy(IR) and inductively coupled plasma mass spectrometry(ICP-MS).Metal processing additives with complex compositions are essential chemical products in metal production.They could easily form the chelates interfering analysis.In this paper,the metal processing additive sample was analyzed by FT-ICR MS combined with NMR,IR and ICP-MS,and sodium citrate and EDTA-Bi chelate were detected.Results showed that the method was simple and accurate,and could be applied in the rapid identification of metal processing additives containing metal chelates.关键词：Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS);inductively coupled plasma mass spectrometry(ICP-MS);nuclear magnetic resonance(NMR);metal processing additives
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发布时间： - 摘要：An ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry(UPLC-Q Orbitrap HRMS) was established for the determination of 17 quinolones in lotions,emulsions and non wax based cream cosmetics.The samples were ultrasonically extracted with 0.1%formic acid and acetonitrile mixed solvent,purified with n hexane,and then separated with an Agilent Poroshell EC C18(4.6 mm×150 mm，2.7 μm) column.The analytes were detected in Full Scan/dd-MS2 mode,and quantified by the internal standard method.Seventeen quinolones showed good linearities in the range of 0.05-200 μg/L with their correlation coefficients(r2) larger than 0.996 0.The limits of detection and quantitation for 17 quinolones were 0.5 μg/kg and 1.0 μg/kg,respectively.Average recoveries for 17 quinolones at three spiked levels of 2，4，20 μg/kg ranged from 82.3%to 108%with relative standard deviations(RSD，n=6) of 3.5%-8.6%.The method is rapid,accurate and sensitive,and is suitable for the determination of quinolone antibiotics in cosmetics.关键词：ultra performance liquid chromatography(UPLC);high resolution mass spectrometry(HRMS);cosmetics;quinolones
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发布时间： - 摘要：Volatile fatty acids(VFAs) are typical malodorous substances,which are at trace levels in the ambient air.A method of gas chromatography-mass spectrometry(GC-MS) was established for the simultaneous determination of seven VFAs ie.acetic acid,propanoic acid,isobutyric acid,butyric acid,acrylic acid,isovaleric acid and valeric acid in ambient air.Ambient air samples were firstly collected with impregnated silica gel tube,then ultrasonically extracted with ultrapure water,finally partitioned with methyl tert-butyl ether,concentrated and set to a certain volume.The target compounds were determined by GC-MS,and quantified by internal standard method.Results showed that the calibration curves for seven VFAs were linear(r2≥0.995) in their respective concentration ranges with the detection limits of 0.11-4.78 μg/m3.The recoveries were in the range of 62.3%-110% with relative standard deviations of 2.2%-12%.The method is simple,accurate and sensitive,and is suitable for the determination of VFAs in ambient air.关键词：ambient air;volatile fatty acids;gas chromatography-mass spectrometry(GC-MS);odor
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发布时间： - 摘要：A method was developed for the rapid detection of 4-methylaminoantipyrine(MAA),4-aminoantipyrine(AA),4-formylaminoantipyrine(FAA) and 4-acetylaminoantipyrine(AAA) in foods of animal origin by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) with a through type solid phase extraction.Samples were extracted with acetonitrile,then cleaned up with a PRiME HLB column,finally quantified by UPLC-MS/MS in MRM mode after gradient elution on an ACQUITY BEH C18 column with acetonitrile and 0.1% formic acid as mobile phases.Results showed that the calibration curves for four analytes were linear in the range of 0.5-50 μg/L with correlation coefficients(r) larger than 0.996.The limits of detection(LODs) and the limits of quantitation(LOQs) were 2 μg/kg and 5 μg/kg,respectively.The average recoveries at three spiked levels of 5,10 and 50 μg/kg ranged from 75.1% to 115%,with relative standard deviations(RSD) of 1.6%-7.4%.The proposed method is simple,rapid and accurate,and could be applied in the simultaneous determination of dipyrone metabolite residues in foods of animal origin.关键词：dipyrone metabolite;through type solid phase extraction;PRiME HLB;ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS /MS);foods of animal origin
- 1140
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发布时间： - 摘要：A method based on QuEChERS coupled with high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) was developed for the determination of ten fluorescent white agents(FWAs) residues in facial mask.After mixed with water，the sample was extracted with acetonitrile,then added NaCl and MgSO4,cleaned up with C18 and primary secondary amine(PSA).The extracts were centrifuged,concentrated,and diluted with acetonitrile,then analyzed by HPLC-MS/MS.Separation of the FWAs was carried out on a C18 column with 10 mmol/L ammonium acetate and acetonitrile by gradient elution.The compounds were detected in positive/negative ion mode under multi reaction monitoring(MRM) mode.The quantitation was performed by exteral standard method.Results showed that there were good linear relationships for the FWAs in a certain concentration range with correlation coefficients(r2) greater than 0.99.In positive mode,the limits of detection(S/N=3) and the limits of quantitation(S/N=10) were in the ranges of 0.05-1.0 μg/kg and 0.2-3.0 μg/kg,respectively,while in negative mode,they both were 0.1-1.0 mg/kg and 0.3-2.0 mg/kg,respectively.The average recoveries for ten FWAs ranged from 64.4% to 106% with relative standard deviations(RSDs) of 2.6%-8.5%.With the advantages of simple operation and high recovery,the method is suitable for the determination of 10 FWAs in facial mask.关键词：high performance liquid chromatography-triple quadrupole mass spectrometry(HPLC-MS/MS);fluorescent white agents(FWAs);facial mask
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发布时间： - 摘要：A rapid screening and quantitative method was developed for the determination of paraquat in vegetables by ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry(UHPLC-Q-Exactive MS).The vegetable samples were extracted twice with acetonitrile -0.2% formic acid(1∶1,by volume),and cleaned up by dispersive solid phase extraction with N propyl ethlene diamine(PSA) and C18.Separation of the target compounds was performed on an Acquity UPLC BEH HILIC(100 mm×2.1 mm,1.7 μm) column with acetonitrile and 0.2% formic acid containing 50 mmol/L ammonium formate as mobile phases by gradient elution.The quantitative and qualitative analysis were carried out by high resolution mass spectrometry with electrospray ionization(ESI) source in positive ion acquisition mode under parallel reaction monitoring(PRM) mode.Results showed that there were good linear relationships for paraquat in different vegetables matrixes in corresponding concentration ranges with correlation coefficients(r2) of 0.992 7-0.999 4.The limits of detection(LOD) and the limits of quantitation(LOQ) were in the ranges of 0.1-0.5 μg/kg and 0.4-1.8 μg/kg,respectively,while the recoveries ranged from 70.8% to 113% with relative standard deviations(RSD) of 0.30%-7.9%.The method is simple and rapid,and could be used for the quick screening and quantitative analysis of paraquat in vegetables.关键词：ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry(UHPLC-Q-Exactive MS);vegetables;paraquat;dispersive solid phase extraction(DSPE)
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发布时间： - 摘要：A fluorescent probe for the detection of penicillin in medicaments was fabricated with iodine-rhodamine B(RB) associate,as the fluorescence signal intensity of RB would be weakened by iodine(I-3) solution or even disappear,while penicillin alkaline hydrolysis product penicillium thiazole could reduce I-3to I-,making the system fluorescent signal reappear.The fluorescent probe was applied in the determination of penicillin in medicaments at an excitation wavelength of 365 nm and an emission wavelength of 580 nm.Results showed that there was a good linear relationship between fluorescence intensity change and penicillin concentration in the range of 0-6 μmol/L with a limit of detection(LOD) of 1.88×10-9 mol/L.The recoveries were in the range of 97.0%-106% with relative standard deviations(n=6) of 2.6%-3.1%.The proposed method was simple,rapid,accurate and reliable,and could be used for the analysis of penicillin in medicaments.关键词：rhodamine B;iodine;penicillin;fluorescence quenching
- 1225
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发布时间： - 摘要：A method was established for the determination of total phosphorus in soil by microwave digestion/inductively coupled plasma-mass spectrometry with collision cell(CCTked).Under the optimized conditions,the internal standard method was used for quantitation,and the accuracy and precision of the method were verified by using the soil reference material.There existed a linear relationship for phosphorus in the soil sample in the range of 0-2 000 μg/L,with the method detection limit of 5 μg/L and a detection limit of 2.5 μg/g for the soil sample.The spiked recoveries for the soil matrix solution were between 94.0% and 103%.There were no significant differences when the results obtained were compared with that of the Mo-Sb anti spectrophotometry.The method was rapid,simple and sensitive,and was suitable for the determination of total phosphorus in soils.关键词：soil;total phosphorus;ICP-MS;microwave digestion
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发布时间： - 摘要：Graphitic carbon nitride(g-C3N4) is a nitrogen rich carbon material with planar graphene like structure,which has received increasingly research interests in recent years.g-C3N4 nano materials have a broad prospect in optical and electrochemical sensors and bio-imaging in analytical chemistry due to their remarkable physicochemical properties,such as electronic band structure,optical and electronic properties,high thermal and chemical stability.An overview on the applications of g-C3N4 nano-materials in fields of optical analysis and electro analysis,etc.is presented in this review.And their further development prospect is also discussed.关键词：graphitic carbon nitride;nanomaterials;analytical chemistry;review
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发布时间： - 摘要：Triplet-triplet annihilation(TTA) upconversion is a technique converting low energy photos into high energy photos by a multi photon mechanism.The TTA based upconversion has a broad application prospect in solar cells,photocatalytic,anti counterfeiting and bioimaging,etc.The traditional TTA based upconversion mainly occurs in anaerobic solution,which may significantly limit its applications.Recently,the development of TTA upconversion in solid state has attracted much attention.And the development over the past ten years of solid state TTA upconversion in polymer matrix from the state of polymer and the dispersion mode of TTA system is summarized in this review.关键词：triplet-triplet annihilation;upconversion;polymer;matrix
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