最新刊期
卷 39 ， 期 8 ， 2020
- 摘要：In this paper,a novel fluorescence probe was designed and synthesized for the detection of HClO based on phenanthroimidazole.The probe 2-(4-(methylthio)phenyl) 1H-phenanthro［9,10-d］imidazole(MPI) was prepared through one step reaction with commercial reagents 9,10-phenanthroquinone and 4 (methylthio)benzaldehyde,and obtained in good yield(85%) by simple filtration and washing.The free MPI displayed relatively weak fluorescence due to the heavy atom effect of sulfur atom.However,addition of HClO into the MPI solution triggered a strong fluorescence at 445 nm as the HClO promoted oxidation of sulfide into sulfoxide reduced the heavy atom effect and strengthened the intramolecular charge transfer(ICT) process.The reaction mechanism of MPI and HClO was confirmed using high resolution mass spectrometry.In PBS buffer(DMF∶H2O=2 ∶8,by volume,pH 7.4),the probe MPI could be used for quantitative detection of HClO in the range of 0-100 μmol/L with a detection limit of 0.26 μmol/L as it has high sensitivity and selectivity to HClO other than other analytes.More importantly,with good biocompatibility and cell membrane permeability,the probe MPI could be applied in the visual imaging of HClO in living cells.Therefore,The probe MPI provides a reliable and effective tool for detection and tracing of HClO in biological systems.关键词：fluorescent probe;hypochlorite;phenanthroimidazole;cell imaging
- 359
- |
- 5
- |
- 4
发布时间：2023-04-18 - 摘要：This study aimed at the investigation of effect of Xuefu Zhuyu decotion(XFZY) on rats with traumatic brain injury(TBI) in plasma metabolomics.The plasma samples from the treatment group,the model group as well as the sham group were analyzed by gas chromatography-mass spectrometry(GC-MS).Forty three important metabolites were qualitatively and quantitatively analyzed.t test was employed for the model group and the sham group,and 13 metabolites were found with significant differences.Orthogonal partial least squares-discriminant analysis(OPLS-DA) was performed on the model group and the sham group.The obvious classification tendency was observed between the two groups.Integrating the variable importance in projection(VIP) and the results of T test,lactic acid,histidine,palmitic acid,tryptophan,linoleic acid,oleic acid,and stearic acid were selected as biomarkers.The treatment group was gavaged with XFZY,and seven biomarkers were used to observe the metabolite changes in treatment groups experiencing the treatment after 1,3,7 and 14 days,respectively.It was found that the relative concentrations of lactic acid,histidine,palmitate,linoleic acid,and stearic acid decreased gradually.The relative concentration of tryptophan decreased at first,and then increased,while the relative concentration of oleic acid showed an opposite trend.A consensus is emerging about the relative concentration of seven metabolites between the sham group and treatment group on day 14.Experimental results showed that XFZY had a good therapeutic effect on TBI.Meanwhile,those metabolites,ie lactic acid,histidine,palmitic acid,tryptophan,linoleic acid,oleic acid and stearic acid could be used as the biomarkers for monitoring the therapeutic effect and recovery of TBI.关键词：Xuefu Zhuyu decotion;traumatic brain injury;gas chromatography-mass spectrometry(GC-MS);metabolomics;chemometrics
- 394
- |
- 6
- |
- 2
发布时间：2023-04-18 - 摘要：A rapid analytical method for the simultaneous determination of 7 lincosamides and macrolides residues in honeys was developed by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).The samples were dissolved with phosphate buffer(pH 8.0),then extracted with 1% ammonia acetonitrile and salted out with anhydrous sodium sulfate.The extract was cleaned up with 80 mg ZnO and 20 mg PSA.The target compounds were separated on a Waters XBridge C18(150 mm×2.1 mm，5 μm) column with 0.1% formic acid solution and acetonitrile as mobile phases,then determined with electrospray ionization source in positive ion mode under multiple reaction monitoring(MRM) acquisition mode,and quantified by external standard method using matrix matched standard solution.Results showed that the 7 target compounds showed good linearity in their respective mass concentration ranges with correlation coefficients(r) not less than 0.999 3.The limits of detection of the method were in the range of 0.21-0.35 μg/kg,while the limits of quantitation were 0.69-1.16 μg/kg.At three spiked levels of 5.0,10.0 and 20.0 μg/kg,the average recoveries for 7 target compounds were in the range of 75.5%-99.0% with relative standard deviations of 0.78%-5.9%.The method could be applied to the rapid determination of 7 lincosamides and macrolides residues in honeys with the advantages of simplicity,rapidness,high sensitivity and good reproducibility.关键词：honey;high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS);lincosamides;macrolides;zinc oxide(ZnO);QuEChERS
- 389
- |
- 4
- |
- 7
发布时间：2023-04-18 - 摘要：A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) with isotope dilution was established for the determination of niclosamide(NIC) in water,sediment,fish muscle and skin in natural proportions and shrimp muscle.The water sample was extracted with ethyl acetate after alkalization treatment,and the other samples were extracted with acetonitrile containing 0.1% ammonia,and purified using C18 powder.The extracts were separated on a Thermo Hypersil Gold C18(150 mm×2.1 mm，5 μm) column with acetonitrile-water as mobile phase at a flow rate of 0.3 mL/min,then detected in selected reaction monitoring(SRM) mode and quantified by internal standard calibration curve method with the stable isotope marker of NIC(NIC-13C6) as internal standard.Results showed that good linearities for NIC in the samples were observed in the range of 0.2-200 μg/L,with their correlation coefficients(r2) not less than 0.999 5.The average recoveries for NIC in water at three spiked levels of 2.5,25 and 250 ng/L ranged from 90.5% to 109% with relative standard deviations(RSD) of 3.2%-11%.The limit of detection(LOD) and limit of quantitation(LOQ) for NIC in water were 1.0 ng/L and 2.5 ng/L,respectively.While for NIC in sediment,fish muscle and skin in natural proportions and Procambarus clarkii muscle,the average recoveries at three spiked levels of 0.5,5.0 and 50 μg/kg were in the ranges of 89.4%-113%,92.8%-110% and 94.1%-107%,with their RSDs of 46%-12%,2.8%-11% and 3.2%-9.3%,respectively.The LODs and LOQs were 0.2 μg/kg and 0.5 μg/kg,respectively.With high sensitivity,accuracy and selectivity,the present method is suitable for the determination of NIC residues in practical aquatic environmental water,sediment,fish and shrimp.关键词：isotope dilution;niclosamide;water;sediment;fish;shrimp;high performance liquid chromatography-tandem mass spectrometry
- 334
- |
- 5
- |
- 1
发布时间：2023-04-18 - 摘要：An ultra-performance liquid chromatography-tandem mass spectrometric(UPLC-MS/MS) method was established for the simultaneous determination of 35 sex hormones in cosmetics.The sample was ultrasonically extracted with 50% acetonitrile solution,and separated on a CORTECS C18(2.1 mm×150 mm，2.7 μm) column by gradient elution using acetonitrile-water as mobile phases.The analysis was performed under multiple reaction monitoring(MRM) mode. Results showed that there were good linear relationships for 35 sex hormones in the respective concentration range with their correlation coefficients(r) all above 0.99．The limits of detection(LOD) and limits of quantitation(LOQ) for 35 sex hormones were in the ranges of 0.028-0.117 μg/g and 0.093-0.352 μg/g,respectively.Average recoveries of toner,emulsion and cream samples at three levels of 0.25,0.50,1.00 μg/g were in the range of 84.0%-117%，with relative standard deviations(RSD,n=6) of 1.5%-14%.With the advantages of simplicity,sensitivity and accuracy,this method is suitable for the analysis of sex hormones in cosmetics.关键词：ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS);cosmetics;sex hormones;determination
- 378
- |
- 4
- |
- 4
发布时间：2023-04-18 - 摘要：A magnetic hydrothermal carbon material(MHC) coated with Fe3O4 nanopaticles was firstly prepared by solvothermal method,using renewable agricultural waste corn silk as the carbon precursor,ferric chloride(FeCl3·6H2O) as the source of iron.Then,a biomass derived activated magnetic porous carbon(AMC) was successfully fabricated via pyrolysis treatment of MHC using KOH as activating reagent.This magnetic nanocomposite,with a well developed porous structure,provided a large number of activated sites for the target absorption.Besides,the iron oxide(Fe3O4 and Fe2O3) homogeneously distributed on the surface of the carbon matrix.AMC exhibited a remarkable adsorption performance toward malachite green(MG),and the maximum adsorption capacity reached up to 312.5 mg/g obtained from the Langmuir isotherm.Combined with ultra high performance liquid chromatography(UPLC),AMC was served as a magnetic solid phase extraction(MSPE) adsorbent to detect MG in water.The important parameters influencing the extraction performance of the adsorbent were investigated and optimized.The best extraction results were obtained when 6 mg AMC was applied to extract MG in 100 mL sample solution(pH 7.0) for 20 min,using a mixture of methanol-acetic acid(9∶1,by volume) as eluent.Results showed that there was a good linear relationship for MG in the concentration range of 0.05-5 μg/L,with correlation coefficient(r) of 0.999 6.The limit of detection(LOD) was 0.01 μg/L,and the limit of quantitation(LOQ) was 0.03 μg/L.The spiked recoveries for MG in the seawater samples ranged from 104% to 106%,with RSDs of 1.7%-3.4%.The developed method was suitable for the detection of MG in aquacultural seawater.关键词：porous carbon;magnetic separation;malachite green(MG);magnetic solid phase extraction(MSPE);ultra high performance liquid chromatography(UPLC)
- 358
- |
- 4
- |
- 2
发布时间：2023-04-18 - 摘要：A gas chromatography-mass spectrometric(GC-MS) method was developed for the simultaneous determination of 31 free fatty acids(FFAs) in plasma.By comparing and optimizing the extraction and derivatization of FFAs from plasma,a solution of chloroform ：methanol(1∶2,by volume) was selected to extract FFAs,and acetyl chloride was used for the FFAs derivatization before GC-MS detection.Results indicated that there were good linear relationships for 31 FFAs in their respective concentration ranges,with correlation coefficients(r) not less than 0.999 0.The limits of detection(LOD) and the limits of quantitation(LOQ) were in the ranges of 0.010-0.050 μg/mL and 0.034-0.167 μg/mL,respectively.When C13∶0 and C23∶0 were used as target compounds to valify the method,the average recoveries for plasma quality ranged from 86.3%-115%,with the intra-day RSDs(n=6) not more than 6.3% and the inter-day RSDs(n=3) not more than 7.8%.The developed method was applied to detect the FFAs in the plasma samples of 49 pregnant women.21-31 FFAs were detected in the plasma,among which C16∶0(palmitic acid),C18∶2n6c(linoleic acid),C18∶1n9c(oleic acid) and C18∶0(stearic acid) were the main fatty acids.With more fatty acids detected,smaller sample volume required,lower LOD and LOQ as well as better accuracy of qualitation and quantitation,the proposed method is more suitable for the analysis of FFAs spectrum in plasma.关键词：free fatty acids;gas chromatography-mass spectrometry;derivatization;plasma
- 351
- |
- 5
- |
- 3
发布时间：2023-04-18 - 摘要：A porous metal oxide NiO used to adsorb tetracycline(TC) in water samples was synthesized by hydrothermal method and subsequent high temperature calcination.The obtained nanomaterial was characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR) and X-ray diffraction(XRD).Results showed that NiO exhibited a clustered flower like porous structure.Effects of pH value,adsorption time,TC concentration and temperature on the adsorption performance of NiO were investigated.The optimal pH value for TC adsorption on NiO was 7.0,and an adsorption equilibrium could be reached in 120 min.The adsorption capacity increased from 26.49 mg/g to 134.84 mg/g when TC concentration varied from 10 mg/L to 100 mg/L.The adsorption process fit well with the pseudo second order kinetic model.The maximum adsorption capacity of NiO for TC was calculated to be 144.90 mg/g by fitting the adsorption date with the Langmuir model.Therefore,with the advantages of reusability,low cost,simple preparation and high adsorption capacity for TC etc.,NiO has a great potentiality in the rapid removal of TC pollutants in polluted water samples.关键词：NiO;hydrothermal method;adsorption;tetracycline;water
- 351
- |
- 4
- |
- 3
发布时间：2023-04-18 - 摘要：The poly(sodium 4-styrenesulfonate) functionalized spong graphene(3D-PSS-rGO) composites were fabricated via a green and simple method.The as made composites were characterized and analyzed by ultraviolet and visible absorption spectroscopy and scanning electron microscopy.An electrochemical sensor was constructed for the detection of daphnetin based on 3D-PSS-rGO composite film modified glassy carbon electrode(3D-PSS-rGO/GCE).Results showed that the 3D-PSS-rGO/GCE exhibited a strong enrichment effect and an excellent electrocatalytic activity towards daphnetin.Under the optimized conditions,good linear relationships were observed between oxidation peak current and daphnetin concentration in the ranges of 0.08-10.0 μmol/L and 10.0-60.0 μmol/L,with a detection limit of 0.04 μmol/L.The sensor was used in the determination of daphnetin content in girald daphne bark,with recoveries of 90.0%-96.0%.This study provides a reference for the determination of daphnetin in medicinal herbs.关键词：poly(sodium 4-styrenesulfonate)(PSS);graphene;daphnetin;sensor
- 329
- |
- 4
- |
- 1
发布时间：2023-04-18 - 摘要：A method based on 1H-NMR and 31P-NMR was established for the quantitative analysis of tris(3 sulfonatophenyl) phosphine sodium salt hydrate(TPPTS).Through one dimensional 1H-NMR,13C-NMR,31P-NMR and two-dimensional 1H-1H COSY,1H-13C HSQC, 1H-13C HMBC,the chemical shift of TPPTS including all the hydrogen atoms,carbon atoms and phosphorus atoms were assigned.Trioxane was selected as the internal standard compound while N,N-dimethylformamide-D7(DMF-D7) was used as solvent in the 1H-NMR test.Correspondingly,KH2PO4 and deuterium oxide(D2O-D2) were used in the 31P-NMR test.The pulse delay time(D1) of the mixing system was set reasonably based on results of the longitudinal relaxation time(T1) test.Quantitative analysis results of TPPTS by 1H-NMR and 31P-NMR were (58.72 ± 0.21)% and (58.51 ± 0.21)%,respectively,which are close and parallel.Meanwhile,there is no need for the standards of the samples to be detected in the process.Thus the rapid and effective determination of TPPTS in the mixing system could be realized.关键词：tris(3-sulfonatophenyl) phosphine sodium salt hydrate(TPPTS);nuclear magnetic resonance(NMR);1H-NMR quantitative analysis;31P-NMR quantitative analysis
- 345
- |
- 4
- |
- 1
发布时间：2023-04-18 - 摘要：A method of gas chromatography-mass spectrometry(GC-MS) was developed for the simultaneous determination of 18 chlorinated hydrocarbon organic solvents in dyeing and finishing auxiliaries.The sample of dyeing and finishing auxiliaries with proper amount of sodium chloride was extracted by oscillation with n-tetradecane,then separated on a DB-624 IU column(30 m×0.25 mm,1.4 μm),and finally detected by GC-MS with EI source in SIM mode.External standard method was used for the quantitative determination.Results revealed that the 18 chlorinated hydrocarbon organic solvents could be separated within 19 min,and their calibration curves showed good linearity in the range of 0.2-100 mg/L with correlation coefficients(r2) no less than 0.999 2.The limits of detection(LODs,S/N=3) and the limits of quantification(LOQs,S/N=10) were in the ranges of 0.033-0.063 mg/L and 0.11-0.19 mg/L,respectively.At three spiked levels of low,medium and high,the average recoveries for 18 analytes in fluorescent brightener 1#(liquid) and softener 2#(solid) were in the ranges of 93.3%-104% and 92.7%-104%,with their relative standard deviations(RSDs) of 3.5%-5.3% and 3.2%-5.4%(n=6),respectively.This method was applied in the determination of 23 dyeing and finishing auxiliaries with different properties,and tetrachloroethylene was detected in 3 dyeing and finishing auxiliaries.With the advantages of high sensitivity,good precision and accuracy,the method is suitable for the determination of chlorinated hydrocarbon organic solvents in all kinds of dyeing and finishing auxiliaries,and provides a good strategy for further quality control of dyeing and finishing auxiliaries.关键词：gas chromatography-mass spectrometry(GC-MS);chlorinated hydrocarbon organic solvents;dyeing and finishing auxiliaries
- 336
- |
- 4
- |
- 0
发布时间：2023-04-18 - 摘要：In this paper,an analytical method was developed for the analysis of benzoic acid and sorbic acid by reversed phase chromatography with imidazolium ionic liquid as mobile phase additive.Effects of imidazolium ionic liquid type and concentration,methanol concentration and ultraviolet detection wavelength on the separation and detection of benzoic acid and sorbic acid were investigated,and the retention rules of the two analytes were discussed.The separation and detection of benzoic acid and sorbic acid were achieved in 7.0 min,with an Agilent ZORBAX ODS reversed phase column using methanol-0.2 mmol/L 1-butyl 3-methylimidazolium chloride aqueous solution(40∶60,by volume) as mobile phase at an ultraviolet wavelength of 230 nm,a flow rate of 1.0 mL/min and a column temperature of 35 ℃.The linear ranges for benzoic acid and sorbic acid ranged from 1.0 mg/L to 100.0 mg/L,with correlation coefficients(r) more than 0999 5.The detection limits for two analytes were both 0.02 mg/L.The method was applied in the determination of benzoic acid and sorbic acid in beverage samples.The spiked recoveries were in the range of 93.9%-104% with relative standard deviations(RSD) not more than 4.0%,which could meet the requirements for quantitative analysis.关键词：reversed-phase chromatography;ionic liquid;benzoic acid;sorbic acid;food additive
- 347
- |
- 4
- |
- 2
发布时间：2023-04-18 - 摘要：A gas chromatography-mass spectrometry(GC-MS) with a novel multi walled carbon nanotubes(MWCNTs) QuEChERS was established for the determination of sixteen kinds of pesticides including α-BHC,β+γ-BHC,δ-BHC,quintozene,p,p′-DDE,o,p′-DDT,p,p′-DDD,p,p′-DDT,metalaxyl,diazinon,heptachlor,cyprodinil,procymidone,chlordane,trans chlordane and fludioxonil, based on the characteristics of Astragalus membranaceus samples.The dry sample powder was mixed with 10 mL of water,extracted with acetonitrile,and then cleaned up with multi walled carbon nanotubes(MWCNTs),n propyl ethylenediamine(PSA) and MgSO4 to remove the interferences of co-extractives.The extract was separated on an HP-5ms capillary column using temperature programming,and detected by GC-MS with EI source in scanning ionic mode(SIM).Under the optimum conditions,there were good linear relationships for 16 pesticides in the concentration range of 0.01-5.0 mg/L,with correlation coefficients not less than 0.974.Moreover,the limits of quantitation(S/N=10) were in the range of 0.002-0.035 mg/kg,and the average recoveries for the pesitides in Astragalus membranaceus ranged from 71.9% to 115% with relative standard deviations(RSDs) of 1.2%-14%.This method provides a new way to evaluate the quality and safety of Astragalus membranaceus with the characteristics of simplicity,rapidness and high sensitivity.关键词：MWCNTs;QuEChERS;gas chromatography-mass spectrometry;Astragalus membranaceus;pesticides
- 371
- |
- 6
- |
- 5
发布时间：2023-04-18 - 摘要：In recent years,chemical terrorist attacks and chemical accidents that have occurred continuously at home and abroad are still a major threat to human survival and national security.Chemical detection is the eye for chemical emergency disposal and rescue.Skillful mastery and proper use of detection equipment are the key factors in dealing with chemical threats and reducing losses and casualties.The detection equipments based on chemical sensing and other techniques possess the characteristics of fast response,intelligence and portability,and have the advantages of remote monitoring and real time duty.In this paper,the principles,performance,advantages and disadvantages of the on site detection equipments including electrochemical sensor,mass sensitive sensor,infrared sensor,Raman sensor,ion mobility spectrometry detector,flame photometric detector,photo ionization detector and remote telemetry sensing equipment are summarized.Specifically,the latest progress of detection equipments dealing with chemical threats is mainly described.The development trend and application prospects of chemical sensing equipments are prospected,which will provide a reference for the further research and application of chemical detection equipments in response to chemical threats.关键词：detection equipment;chemical sensors;chemical warfare agents(CWAs);explosives;toxic industrial chemicals(TICs)
- 363
- |
- 4
- |
- 0
发布时间：2023-04-18 - 摘要：Nuclear magnetic resonance(NMR) is one of the most commonly used analytical methods for determination of molecular structure,while diffusion ordered spectroscopy(DOSY) expands the ability of NMR for analysis of complex mixtures.DOSY could “virtually separate” those chemical entities presenting in a multi-component system by measuring the self diffusion coefficient of the component,which reflect the effective size and shape of molecules.Furthermore,DOSY could also provide specific information on molecular size,molecular weight,intermolecular interaction and aggregation state.the basic principles of DOSY experiments,the development of pulse sequences and the application progress of DOSY in related research fields are summarized in this article.Firstly,the development and application characteristics of pulsed field gradient and pulse sequences are briefly described,then the research progresses of DOSY in identifying mixture components,measuring molecular size and molecular weight distribution,and characterizing intermolecular forces are introduced.The wide applications of DOSY in chemistry,pharmacy,food,biology and other fields are exhibited by citing examples.关键词：diffusion ordered spectroscopy;diffusion coefficient;pulsed field gradient;pulse sequence
- 368
- |
- 4
- |
- 0
发布时间：2023-04-18 - 摘要：Inductively coupled plasma mass spectrometry(ICP-MS) is the most commonly used detection technique in trace element analysis.Although ICP-MS shows many advantages in elemental analysis,it still encounters many problems when samples with complex matrices are detected.Suppression or enhancement of the analyte signals is often observed in the presence of matrix effects.The degree of matrix effect depends not only on the absolute concentration of matrix components,but also on the type of matrix,the physical and chemical properties of the analyte and the instrument conditions.Several types of common matrix effects and the influencing factors in ICP-MS are introduced in this article,including elemental matrix,carbon contained matrix,acid matrix and instrument conditions,etc.The possible causes of matrix effects are explored.The methods for removing matrix effects,such as sample pretreatment methods,sample introduction system,instrument optimization and calibration methods etc.,are systematically summarized in this article.Besides,in the conclusion,the development tendency for analysis of matrix effects is also summarized and looked forward to.关键词：inductively coupled plasma mass spectrometry(ICP-MS);matrix effects;sample pretreatment;sample introduction system;instrument parameters;calibration strategies;review
- 387
- |
- 6
- |
- 4
发布时间：2023-04-18
- Address：100 Xianlie Middle Road, Guangzhou Postal code：510070
- Tel：020-87684776,37656606 Fax：020-87684776 Email：fxcsxb@china.com
- Technical support is provided by Beijing Founder electronics co., LTD 粤ICP备12017312号-3
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0