最新刊期
卷 33 ， 期 9 ， 2014
- 摘要：A self-mode lab’s high sensitive atomic fluorescence spectrometric detection system combined with liquid chromatography，online ultraviolet photochemical digesting and vapor generation device was established and evaluated.Arsenic and selenium species in various samples were extracted by heating-shaking and centrifugal filtration.All the analytes were separated on a reversed-phase column using mobile phase of 5.0 mmol/L phosphate buffer(pH 5.7)-0.5 mmol/L tetrabutyl ammonium bromide(TBAB)-1%methanol.The separations of AsO3-3，DMA，MMA，AsO3-4 and SeCys，SeMet，SeO2-3，SeO2-4 were achieved within 7 min and 11 min，respectively.Under the optimized operating conditions，the detection limits(DLs，S/N=3) were in the range of 0.08-0.74 μg/L,and the relative standard deviations(RSD，n=7) were 1.4%-7.9%.The standard spiked recoveries for real samples were in the range of 82.5%-116.5%.Linearities were obtained in the ranges of 0.28-40.0 μg/L for arsenic species and 0.38-80.0 μg/L for selenium species.The developed system was successfully applied in the detection of low levels of arsenic and selenium species in matrices.关键词：speciation analysis;high sensitive atomic fluorescence spectrometric system;arsenic;selenium
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发布时间： - 摘要：Bufadienolide is a kind of natural steroids with significant anti-cancer activities.Hitherto，the number of structural modification on the bufadienolides has reached more than 100.The purification of sulfated，a trace cytotoxic component bufadienolides from toad skin is a tough work due to its low content and unstable structures.However，there is no report on synthesis of bufadienolides sulfonation though they have promising cytotoxic activities.In this paper，the arenobufagin was firstly taken as an example，to develop an effective method for the synthesis of arenobufagin 3.O sulfonate.In order to enrich the arenobufagin 3.O sulfonate quickly and mildly，a reversed phase/hydrophilic solid phase extraction method based on our homemade hydrophilic Click TE-Cys was developed.The structures of arenobufagin 3.O sulfonate and arenobufagin were both identified by MS，1H NMR and 13C NMR spectra.In addition，the total bufogenins were sulfonated by this method and the sulfated bufogenins were also successfully enriched via the reversed phase/hydrophilic solid-phase extraction approach.Finally，a LC-MS system was employed to test the result,and about 20 sulfated bufogenins were primarily identified according to their molecular weight.Based on this，a systemic method was first developed for the synthesis and enrichment of the sulfated total bufogenins and a large number of potential anticancer new compounds were obtained，which provided lots of agents for further screening to achieve high effective and low toxic compounds.The efficient reversed phase/hydrophilic solid-phase extraction method for the enrichment of sulfated bufogenins could be used to enrich sulfated bufogenins in toad skin extract.关键词：bufadienolides;arenobufagin;sulfated bufogenins;solid phase extraction
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发布时间： - 摘要：Two 8-hydroxyquinoline derivatives of（E）-2-［2-（2,4,6-trifluorophenyl）vinyl］-8-hydroxylquinoline（B）,（E）-5-［2-（2,4,6-trifluorophenyl） imino］-8-hydroxyquinoline（C） and their zinc complexes D and E were designed and synthesized,and identified by NMR，IR，MS spectra and elemental analysis.The aggregation behaviors of Zn（AcO）2 and the ligands B and C were investigated by UV-vis spectrum in methyl solution.The luminescence properties of the compounds B and C were investigated by fluorescence spectra in methol solution at room temperature.The results showed that the fluorenscence peaks of compounds D and E were 599 nm and 572 nm，respectively.Their fluorescence properties showed that the luminescence wavelengths of 5-substitued-8-hydroxyquinoline derivatives and 2-substitued-8-hydroxyquinoline derivatives shift to red compared with that of 8-hydroxyquinoline.Meanwhile，the results for determination of solid fluorescence lifetime showed that the complex of D had a long fluorescence lifetime.关键词：8-hydroxyquinoline;zinc complexes;1H NMR tradition;UV-vis spectrum;fluorescence spectrum
- 2021
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发布时间： - 摘要：19 pesticide residues in substrates of different pigments including apple,tomato,ginger and leek,were determined by UPLC-MS/MS.Through comparing four kinds of purification methods,the best detection method was selected.The samples were purified by solid phase extraction（SPE） and dispersed solid phase extraction（QuEChERS）.The SPE columns included TPS column,PC/NH2 column and NH2 column.The absorbent of QuEChERS was the mixture of PSA（N-Propyl ethylenediamine） and C18.The detection was performed in multiple reaction monitoring mode,and quantified by the external standard method．The results indicated that the calibration curves of 19 pesticides were linear in the range of 5-100 μg/kg with correlation coefficients more then 0.99．The adsorption effect of TPS column on pigment is best,while the worst one is PSA+C18.The average recoveries for all pesticides in the four substrates purified with TPS column,NH2 column and PSA+C18 were in the range of 72%-107%,71%-110% and 72%-108%,respectively.The recoveries of carbendazim in gingers and leek purified with PC/NH2 column were very low,while those were even zero in apples and tomatoes.The recoveries of the other 18 pesticides were in the range of 71%-110%.The RSDs of phoxim were generally higher than the others,and those of the other pesticides were less than 20% after cleaned up with TPS column,PC/NH2 column,NH2 column and PSA+C18.The limits of detection（LOD ） were in the range of 0.001-3,0.007-3,0.02-4 and 0.02-2 μg/kg for 19 pesticides,with limits of quantitation（LOQ） of 0.003-10，0.02-10，0.06-15 and 0.05-8 μg/kg,respectively.The study provided a reliable basis for accurate,efficient and economical detection of targeted analytes.关键词：UPLC-MS/MS;solid phase extraction;dispersive solid phase extraction;pigment;pesticide residues
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发布时间： - 摘要：A high sensitive performance liquid chromatography-electrospray ion trap-mass spectrometric（LC-MSn） method was developed for the determination of the major methyl protodioscin metabolites（MPD） in rat’s plasma，urine，bile and feces in order to discover its in vivo metabolism pathway.The Sprague-Dawley rats were given a single intravenous injection of 40 mg/kg MPD，and 30 min blood sample，24 hour bile sample，48 hour urine sample and feces samples after administration were collected.The in vivo samples were extracted by solid phase extraction（SPE）.The extracted samples were separated with Phenomenex Gemini C18 column，using methanol（B）-water（A） as mobile phase by elution gradient.The flow rate was set at 1.0 mL/min.The column temperature was 30 ℃.Total of fourteen metabolites in rat biosamples were detected under negative and positive modes .Six of them were identified by comparing HPLC retention times and mass spectra with those of authentic standards.They were protodioscin（M3），26-O-β-D-glucopyrannosyl-（25R）-furan-5-ene-3β,22α,26-trihydroxy-3-O-α-L-rhamnopyranosyl-（1→2 or 4）-β-D-glucopyranoside（M5），MPD（M0），Pseudoprotodioscin（M7），26-O-β-D-glucopyrannosyl（25R）-furan-5-ene-3β,26-dihydroxy-22-methoxy-3-O-α-L-rhamnopyranosyl-（1→ 4）-β-D-glucopyranoside（M9） ，26-O-β-D-glucopyrannosyl（25R）-furan-5-ene-3β,26-dihydroxy-22-methoxy-3-O-α-L-rhamnopyranosyl-（1→2）-β-D-glucopyranoside（M10） and dioscin（M11）.Five of them were proposed based on the MS fragmentation characteristics of metabolite contrast.The results indicated that protodioscin and dioscin were two primary metabolites，and the formation routes of these two metabolites were the major metabolic pathways of MPD in rat.Deglycosylation was found to be the primary reaction.Most of the metabolites belong to phase I,except 2-metabolites belong to phaseⅡreaction and most of the structure changes took place in sugar part rather than in mother nucleus.关键词：methyl protodioscin;LC-MSn;rat;intravenous administration;metabolites in vivo
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发布时间： - 摘要：An electrode-modified by gold nanoparticles(AuNPs) and polymerized film of melamine(PMel)(PMel/Au/GCE) was fabricated.Electrochemical impedance spectroscopy(EIS) was used for analyzing the modified electrode.The electrochemical behavior of rutin was investigated by cyclic voltammetry(CV)，and a couple of sensitive and reversible redox peaks were obtained with an oxidation peak at 0.422 V and a reduction peak at 0.374 V.It was found that the oxidation peak current(Ipa) and the reductive peak(Ipc) current at PMel/Au/GCE were obviously larger than those at bare glassy carbon electrode(GCE) and the electrode modified by polymerized film of melamine(PMel/GCE)，which indicated that the sensitivity for detection of rutin was improved.Experimental parameters，including pH value of buffer solution，electro-deposited time of AuNPs，electro polymerized time of PMel and scan rate were optimized.The differential pulse voltammetry(DPV) was used for the quantitative analysis on rutin.Good linear relationships between current intensities and rutin concentrations were obtained in the ranges of 7.8×10-9 -1.2×10-6 mol/L and 1.2×10-6-1.5×10-5 mol/L，with correlation coefficients(r2) of 0.997 and 0.993，respectively.The detection limit(S/N=3) was 5.5×10-9 mol/L.The modified electrode was applied in the determination of rutin in rutin tablets with recoveries of 96.4%-101.8%.关键词：poly-(melamine);gold nonoparticles;rutin;differential pulse voltammetry
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发布时间： - 摘要：A novel analytical method was developed for the determination of alkyl sulfonates by high performance liquid chromatography-indirect ultraviolet detection using imidazolium ionic liquid as the background ultraviolet absorption reagent without ultraviolet absorption.Chromatographic separation was performed on a reversed-phase C18 column using imidazolium ionic liquid-organic solvent as mobile phase.Effects of detection wavelength,kinds and concentrations of organic solvents and imidazolium ionic liquids,and other parameters on the separation and determination of alkyl sulfonates were investigated.The retention rules of the alkyl sulfonates under different chromatographic conditions were discussed and the chromatographic conditions were optimized.The successful separation and detection of two alkyl sulfonates(sodium pentanesulfonate and sodium heptanesulfonate) were achieved using the optimized mobile phase of 0.7 mmol/L 1-ethyl-3-methyl-imidazolium tetrafluoroborate(pH 3.0,adjusted with 2 mmol/L monosodium phosphate-phosphoric acid)-methanol(55∶45) at a flow rate of 1.0 mL/min,a detection wavelength of 210 nm and a column temperature of 30 ℃.Under the optimal conditions, two alkyl sulfonates could be successfully separated in 10 min.The calibration curves showed good linearities in the ranges of 0.8-200 mg/L and 2.5-200 mg/L for two alkyl sulfonates,respectively,with correlation coefficients above 0.999.The detection limits of two alkyl sulfonates were 0.24 mg/L and 0.75 mg/L,respectively.The method was applied in the determination of environmental water samples,with spiked recoveries of 98.3%–99.1% and relative standard deviations less than 1.5%.The method was simple,accurate and reliable,and could meet the requirements for quantitative analysis.关键词：high performance liquid chromatography;indirect ultraviolet detection;alkyl sulfonates;imidazolium ionic liquids
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发布时间： - 摘要：A sample pretreatment coupled to high performance liquid chromatography with fluorescent detector(HPLC/FLD) method was developed for the determination of 7 anionic fluorescent whitening agents(FWAs)，including fluorescent brightener 353(MST)，2,2′-(1,2-ethenediyl)bis(5-((4-(bis(2-hydroxyethyl)amino)-6-((4-sulfophenyl)amino)-1,3,5-triazin-2-yl)amino)-benzenesulfonicacitetrasodiumsalt(ABP)，disodium 4,4′-bis［(4-anilino-6-hydroxyethylamino-1,3,5-triazin-2-yl)amino］stilbene-2,2′-disulphonate(VBL)，2,2′-((1,1′-biphenyl)-4,4′-diyldi-2,1-ethenediyl)bis-benzenesulfonicaci(4BK)，2,5-bis(5-tertbutyl-2-benzoxazlyl)phiophene(CBS)，disodium 4,4′-bis［(4-anilino-6-morpholino-1,3,5-triazin-2-yl)amino］stilbene-2,2′-disulphonate(CXT) and sodium 4-［3-(4-chlorophenyl)-4,5-dihydro-5-phenyl-1H-pyrazol-1-yl］benzenesulphonate(WG) in textile.The samples were extracted with water-methanol(25∶75)，and directly qualitatively and quantitatively analyzed by HPLC/FLD.The separation of target compounds was performed on a Phenomenex Gemini 5u C18(150 mm×4.6 mm，5 μm) column by gradient elution using acetonitrile-water(containing 2.5 mmol/L ammonium acetate) as mobile phase.The calibration curves of 7 anionic FWAs showed good linearities with correlation coefficients not less than 0.999 6.The limits of quantitation(LOQs，S/N=10) were in the range of 0.1-5.0 mg/kg.The recoveries of 7 anionic FWAs in negative cotton and wool at three spiked levels ranged from 89.5% to 98.9% with relative standard deviations(RSDs) of 2.4%-4.7%.With the advantages of simplicity，high sensitivity and time-saving，this metsod has a certain practical value.关键词：anionic;fluorescent whitening agents(FWAs);high performance liquid chromatography/fluorescent detector(HPLC/FLD);textile
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发布时间： - 摘要：A simple，rapid and effective method for the quantitative analysis of quercetin in Gynostemma pentaphyllum was established by using excitation-emission matrix (EEM) fluorescence coupled with second-order calibration based on Parallel factor analysis(PARAFAC) algorithm，alternating trilinear decomposition (ATLD) algorithm and self weighted alternating trilinear decomposition (SWATLD) algorithm.Al(Ⅲ) was used as fluorescence sensitizer to increase the quercetin fluorescence intensity.The core-consistency diagnostic(CORCONDIA) test indicated the number of components should be two，one of the components corresponds to the quercetin，and the other is related to a coexistence component of traditional Chinese medicine.The content of quercetin by PARAFAC，ATLD，SWATLD with component number N=2 are 0.274 9%,0.272 9% and 0.272 7%，and the average recoveries were 96.3%，103.1% and 96.8%，respectively.The resolved quercetin spectra overlap almost completely with real spectra.The experimental results showed that the chemometrics “second order correction” method was simple，rapid，high efficient and low cost，and could be used for complex component qualitative and quantitative analysis.In addition，the influence of the inner filter effect on fluorescence intensity was discussed，and the results revealed that ultraviolet correction could effectively improve the accuracy of quantitative analysis.关键词：second-order calibration;3D fluorescence;inner filter effects;absorbance correction;quercetin
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发布时间： - 摘要：The modification of cordierite honeycomb ceramics surface by acid corrosion and coating method was mainly studied in this paper.The cordierite honeycomb ceramics carrier surface modification effect was detected by BET,SEM,XRD and EDS,respectively.The results showed that the cordierite honeycomb ceramics coating modified alumina sol after 800 ℃ calcination was beneficial to increase the quantity of cordierite honeycomb ceramics mesoporous，so as to improve the surface performance of cordierite honeycomb ceramics.关键词：catalyst carrier;cordierite honeycomb ceramics;acid corrosion;coating method
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发布时间： - 摘要：A rapid and high-throughput analytical method was developed for the determination of vitamin K1 using photo-induced chemiluminescence(PICL) detection.This method is based on ultraviolet irradiation(254 nm/15 W) of vitamin K1 to produce a fluorescent product which could be determined by peroxideoxalate chemiluminescence system using chemiluminescence detector.Influence of imidazole on photochemical product structure and chemiluminescence mechanism were studied.Under the optimum conditions，a good linear relationship between chemiluminescence intensity and concentration of VK1 over the range of 0.007-3.333 μg?mL-1 was obtained.The detection limit(S/N=3) for vitamin K1 was 2.2 ng?mL-1，and the relative standard deviation(c=01 μg?mL-1 ，n=11) was 2.7%.The method could be used to analyze 96 samples in 10 min,and was successfully applied in the determination of vitamin K1 in injection and human serum by standard addition calibration，with recoveries of 96.0%-104.0%.The results showed that the PICL method was rapid，high-throughput，simple，sensitive and selective,and was especially suitable for the analysis of a large number of samples.关键词：vitamin K1;high-throughput;ultraviolet irradiation;chemiluminescence;human serum
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发布时间： - 摘要：A gas chromatographic method coupled with solid phase microextraction（SPME/GC） was developed for the determination of 13 chlorinated anilines residues in water.The instrumental parameters were optimized.The impact factors of extraction efficiency such as fiber type,extraction temperature,absorption time,pH value,ionic strength and desorption time were also studied.Under the optimized conditions,the calibration curves were linear in certain concentrations.The detection limits were 0.05-0.34 μg/L.The spiked recoveries of analytes in actual sample ranged from 76.0% to 121% with relative standard deviations of 0.3%-17.2%.The proposed method is suitable for the quick determination of trace level of 13 chlorinated anilines residues in water.关键词：solid-phase microextraction;quick determination;water;chlorinated anilines
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发布时间： - 摘要：A simple，rapid，and low cost method based on dispersive liquid-liquid microextraction(DLLME) and fluorescence enhancement spectrophotometry was developed to detect aflatoxin M1(AFM1) in dairy products.Methylene chloride(CH2Cl2) and acetonitrile were used as extracting agent and dispersant，respectively.The extract was detected by fluorescence spectrophotometry.Under the optimum conditions，good linear relationships were obtained for AFM1 in the concentration range of 0.05-2.00 μg/L with correlation coefficients(r) of 0.995 6(milk) and 0.998 9(milk powder).The limits of detection(LOD) were 0.023 μg/L for milk and 0.039 μg/L for milk powder.The spiked recoveries were in the range of 76.7%-95.7%with relative standard deviations(n=6) lower than 5%.The method could be applied in fast detection of aflatoxin M1 in dairy products,and there is no significant difference between this method and the national standard method.关键词：dispersive-liquid-liquid-microextraction(DLLME);fluorospectrophotometry;dairy products;aflatoxin M1
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发布时间： - 摘要：Bleomycins（BLMs）,a family of glycopeptides-derived antibiotics,are widely used as available chemotherapeutic agents against a variety of cancers.In the presence of Fe（Ⅱ） ions,BLM form a binary BLM?Fe（Ⅱ）complex that can activate molecular oxygen.Herein,it is demonstrate for the first time that BLM?Fe（Ⅱ） complex may possess an intrinsic peroxidase-like activity and could catalyze 2,2’-azino-bis（3-ethylbenzthiazoline-6-sulfonic acid）（ABTS） into colored product in the presence of hydrogen peroxide.Experimental results revealed that the catalytic activity of BLM?Fe（Ⅱ） complex is strongly dependent on pH value and temperature,which is similar to natural enzymes such as horseradish peroxidase.The conditions for maximum catalytic efficiency were determined to be pH 6.0 and 30 ℃.Taking advantage of the color reaction of ABTS catalyzed by BLM?Fe（Ⅱ） complex,a simple and rapid colorimetric method for the detection of BLM was thus established.Under the optimal conditions,a good linear relationship was obtained over BLM concentration in the range of 0.1-2.5 μmol/L with a detection limit of 14.1 nmol/L.With the advantages of good reproducibility and high selectivity,the method is anticipated to have a practical potential for BLM analysis in clinical applications.关键词：bleomycin;peroxidase mimetic;UV-Vis spectrum;colorimetric detection
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发布时间： - 摘要：An extraction method of heliotrine was developed by focused microwave-assisted extraction(FMAE).Orthogonal design was used to optimize the experimental conditions.The optimum extraction conditions were as follows: 60 mesh size of material，solvent-materail ratio:1∶35，microwave power:420 W and extraction time:50 min.The analyte was determined by HPLC using methanol -0.05%triethylamine(pH 7.5 )(30∶70) as mobile phase with a detection wavelength of 220 nm.The linear range of heliotrine was in the range of 52-1 040 mg/L(r=0.999 9)，with a detection limit of 0.040 2 mg/L.The recoveries for heliotrine were in the range of 97.5%-103%with RSDs of 2.4%.The method was simple and highly sensitive.关键词：focused microwave-assisted extraction;Cynoglossum amabile Stapf et Drumm;heliotrine;high performance liquid chromatography(HPLC)
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发布时间： - 摘要：Phosphorus concentration with aluminum(Al) compound is a pretreatment method for the dissolved phosphorus analysis by 31P-NMR.In order to apply this method to concentrating phosphorus in freshwater of Lake Taihu，experiment conditions of this method were analyzed，including pH of water during Al precipitating dissolved phosphorus，amount of Al compound，volume of water and type of extractant.The results showed that the amount of Al compound needed in the phosphorus enrichment is related to not only the phosphorus concentration in freshwater，but also the volume of water.The best experiment conditions and procedures to concentrate phosphorus for 31P-NMR analysis were selecting 20 L filtration water from Lake Taihu，and adding 3 g AlCl3?6H2O in the water (keeping pH value of 6.0).After overnight，Al floc containing phosphorus was collected and then redissolved in 0.5 mol?L-1 NaOH+0.1 mol?L-1 EDTA.关键词：concentration of phosphorus;water;Lake Taihu;31P nuclear magnetic resonance (31P-NMR)
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发布时间： - 摘要：A high performance liquid chromatographic（HPLC） methord was developed for the simultaneous determination of 14 forbidden colorants（Metanil Yellow,Solvent Blue 35,Solvent Red 49,Acid Violet 49,Tetramethylpararosaniline Chloride（TMPC）,Pigment Orange 5,Pigment Red 53,Pentamethyltriphenylmethane（PMTPE）,Sudan Red Ⅱ,Hexamethylenepararosaniline Chloride（HMPC）,Solvent Red 24,Rhodamine B,Disperse Yellow 3,Sudan Red Ⅰ） in cosmetics.Cosmetic samples were extracted and dispersed with tetrahydrofuran,and some matrixes were precipitated out after additon of ammonium acetate solution and methanol.After centrifuged and filtered，the extract was separated on an Agilent poroshell 120 EC-C18 column（2.7 μm，3.0 mm×100 mm） by a gradient elution with 10 mmol/L ammonium acetate-acetonitrile as mobile phase.Detection wavelengths were set at 416,514,590 nm,respectively.The qualitative analysis was based on chromatographic retention time and UV spectrum,and the quantitative analysis was performed by the standard curve method of peak area.The linear ranges of 14 analytes were in the range of 0.2-20 μg/mL,with correlation coefficients more than 0.999.The limits of quantitation（LOQs） were in the range of 3-10 μg/g.The average recoveries at three spiked levels ranged from 91.3% to 110.9% with RSDs less than 10%.This method was accurate,simple,sensitive and reliable,and could be used for the analysis of 14 forbidden colorants in cosmetics.关键词：forbidden colorants;cosmetics;high performance liquid chromatography（HPLC）
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发布时间： - 摘要：Plasmid DNA，a common tool of genetic engineering containing the independent genetic structure of the replication,is widely used in basic research of molecular biology，genetically modified detection，medical diagnosis and gene therapy- Plasmid DNA conformations are generally divided into three types：supercoiled，open circle and linear.Crude plasmid DNA often mixes with three configurations，and the amount of protein，RNA，endotoxin with the host genome DNA.These impurities need to be further refined as they affect subsequent applications.The new applications of plasmid DNA,refined technologies and products based on chromatography system，and quality analysis of purified plasmid DNA is reviewed in this paper.Finally，the trends of technology of high purity plasmid DNA and analysis of refined product are presented.关键词：supercoiled plasmid DNA;fine purification;chromatography;digital PCR;review
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