最新刊期
卷 33 ， 期 2 ， 2014
- 摘要：With the strong support from Chinese government,lots of new researchers on traditional Chinese medicines(TCMs) from different aspects have been developing in order to explore the working mechanism of Chinese medicines.The analysis and quality control of Chinese medicines are steadily moving towards an integrative and comprehensive direction,in order to better address the inherent holistic nature of TCMs with the help of new analytical techniques,including chemical and biological ones.The new techniques in analysis of traditional Chinese medicines and their quality control are firstly reviewed briefly in the paper.Several techniques for quality control of Chinese medicines are discussed in some detail.It is illustrated that the quality of Chinese medicines could be efficiently controlled with the help of modern analytical techniques.关键词：Chinese medicines;quality control;new analytical techniques
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发布时间： - 摘要：The aim of this research is to provide a scientific basis for quality control of Houttuynia cordata Thunb through the analysis of the volatile components under different light intensities by gas chromatograph-mass spectrometry(GC-MS) combined with chemometric methods.The volatile oils were extracted by steam distillation and analyzed by GC-MS.The similarities and differences among volatiles under different light intensities were analyzed by chromatographic fingerprint,principle component analysis and similarity evaluation.The overlapping chromatographic peaks were deconvoluted by heuristic evolving latent projections(HELP) method.The qualitative and quantitative analysis were performed by NIST standard mass spectral library combined with relevant literature and peak area normalization method.T-test was used to compare the differences of volatile constituent contents among different groups.There were some similarities and differences in volatile oil fingerprint among 3 groups under different light intensities.Totally,33 compounds were identified in the volatile oil from 3 groups,of which 26 components were common to all materials.The content of monoterpenoids had the positive correlation with light intensity,and the content of non-terpenoids had the negative correlation with light intensity.The content of sesquiterpenes had no relation with light intensity.The t-test results indicated that there was significant difference in the content of some common compositions.The content of decanoyl acetaldehyde and 2-undecanone in group with full light were significantly lower than the other two groups with shading.The results suggested that moderate shading was beneficial to the improvement of content of effective components in Houttuynia cordata Thunb volatile.The type and content of volatile components in Houttuynia cordata Thunb were closely related to the growth conditions.关键词：gas chromatograph-mass spectrometry(GC-MS);light intensity;volatile components in Houttuynia cordata Thunb;fingerprint
- 2154
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- 1055
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发布时间： - 摘要：Hydrophilic interaction liquid chromatography(HILIC) was selected to separate glucosides according to their structure characteristics.The insufficient of selectivity of reversed-phase chromatography(RPLC) would be made up.Firstly,the separation effects of 14 glucosides by both HILIC and RPLC columns were compared.The orthogonality was evaluated.Then the 2-D RPLC/HILIC system was used to separate American ginseng extract.The results showed that the glucosides were well reserved on both HILIC and RPLC columns.But the sequence of peaks was very different.Ginsenoside Rg1 and Re could not be separated with RPLC column,but they could be separated absolutely with HILIC column.The RPLC and HILIC modes had a high orthogonality.The peak capacity and separation ability were well increased for analyzing American ginseng extract by this 2-D RPLC/HILIC system.It was beneficial to the discovery of new compounds.This method was simple,and the mobile phase was compatible with both chromatographic modes.It could be used as the effective means for separation and preparation of glucosides.Also,it could provide a reference for the analysis of other complex traditional Chinese medicines.关键词：glucoside;saponin;hydrophilic interaction liquid chromatography(HILIC);2D-liquid chromatography
- 2340
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- 1157
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- 10
发布时间： - 摘要：In three-dimensional(3D) fluorescence spectra,both arctiin and arctigenin presented two fluorescence peaks with excitation wavelengths（λex） of 230 nm and 280 nm,separately,and all peaks with emission wavelength（λem） of 310 nm.The fluorescence intensity of arctiin was much stronger than that of arctigenin.Acidity possesses great influence on fluorescence intensities of arctiin and arctigenin.When pH was larger than 13.0,the fluorescence of arctiin was enhanced,but the fluorescence of arctigenin was quenched.The 3D fluorescence spectrum and the thin layer fluorescence chromatogram of Arctii Fructus(AF) crude drugs revealed that the fluorescent component of AF was mainly arctiin,whereas arctigenin and other components had no interference with the fluorescence of arctiin in strong alkaline condition.Accordingly,methanol was used as solvent to extract arctiin from AF sample,and the extraction solution was diluted properly with water and adjusted to pH 13.0.Then,the content of arctiin was determined at wavelengths of λex/λemequal to 280 nm/310 nm.The calibration curve for arctiin was linear in the concentration range of 0.014 5-2.03 mg?L-1,the regression equation was IF=2.7+148.7ρ(mg?L-1),with correlation coefficient(r) of 0.999.The method was applied in the analysis of arctiin in an AF control medicinal materials,with a content of 6.01% and a spiked recovery of 98.1%.The method was verified by a thin layer chromatography-fluorescence scanning method,and the results demonstrated that this method was reliable,and could be used for the quality evaluation of AF crude drugs.关键词：arctiin;arctigenin;Arctii Fructus（AF）;fluorimetric analysis;3D fluorescence
- 2340
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- 1155
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- 1
发布时间： - 摘要：A high performance liquid chromatography time-of-flight mass spectrometry(HPLC-TOF-MS) and high performance liquid chromatography ion trap mass spectrometric(HPLC-IT-MS) method were used for the identification of constituents of “Huangzhenlong(HZL)” and “Pingantang(PAT)” Bansha herbal tea(BHT).The results showed that HZL and PAT BHT contained 40 major chemical constituents.By comparing the mass spectrometric data of each constituent with those of literature,17 of the 40 constituents were identified.Among them,13 were confirmed by the comparison of their retention time and MS data with those of reference substances.In addition,chemical fingerprints of HZL and PAT BHT were established by HPLC-IT-MS,and principal component analysis(PCA) was performed to evaluate the quality consistency and stability of 41 batches of BHT samples.PCA results showed that HZL and PAT BHT samples were significantly different,indicating their formulas and the production processes were different.The developed fingerprinting method was fast,efficient and robust for the quality control of BHT products.关键词：Bansha herbal tea;chemical constituents;fingerprint;quality control;high performance liquid chromatography coupled with mass spectrometry
- 2257
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- 1160
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- 7
发布时间： - 摘要：The electrochemical behaviors and electrochemical kinetic of paeonol(PN) at 3-aminopropyltriethoxysilane and ［BnMIM］PF6 modified carbon paste electrode (APTS-［BnMIM］PF6/CPE) were investigated.The electrochemical kinetic parameters of PN at APTS ［BnMIM］PF6/CPE were determined by cyclic voltammetry(CV) and chronoamperometry(CA).The experimental results indicated that PN electrochemical behavior exhibits an irreversible electrochemical oxidation process at APTS-［BnMIM］PF6/CPE.The oxidation peak current of PN versus its concentration had a good linear relationship in the concentration ranges of 9.0×10-7-2.0×10-4 mol?L-1,3.0×10-4-1.5×10-3 mol?L-1 with a detection limit(LOD,S/N=3) of 3.5×10-8 mol?L-1 and a limit of quantitation(LOQ,S/N=10) of 1.2×10-7 mol?L-1.The proposed method was successfully applied in the determination of PN contents in injection samples with their relative standard deviations of 0.58%-2.4% and recoveries of 96.0%-102.0%.关键词：paeonol;3-aminopropyltriethoxysilane;［BnMIM］PF6;modified carbon paste electrode;electrochemical method
- 1995
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- 1022
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- 3
发布时间： - 摘要：A high performance liquid chromatographic(HPLC)method was developed for the simultaneous determination of monomethyl fumarate(MMF)and dimethyl fumarate(DMF)in Chinese herbal medicine.Samples were extracted with ethyl acetate，purified with NH2-carb solid phase extraction column，separated with C18 column，and determined with diode array detector(DAD).The results showed that there were good linear relationships between peak areas and concentrations of MMF and DMF in the range of 0.025-5.0 μg/mL，with limits of detection(LODs)of 0.015 and 0.020 mg/kg，and limits of quantitation(LOQs)of 0.05 mg/kg and 0.06 mg/kg，respectively.The mean recoveries of MMF and DMF at spiked levels of 0.1，0.2，0.5 mg/kg were in the range of 78.9%-97.3%，with relative standard deviations(RSDs，n=6)of 1.7%-6.0%.This method is sensitive and reliable，and could meet the requirements for simultaneous detections of MMF and DMF in Chinese herbal medicine.关键词：high performance liquid chromatography(HPLC);Chinese herbal medicine;monomethyl fumarate;dimethyl fumarate;residual detection
- 2463
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- 1168
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- 2
发布时间： - 摘要：A sensitive,label-free electrochemical immunosensor based on the combination of polythionine/methylene blue(PTH/MB)and gold nanoparticles(GNPs)amplification was proposed for the determination of okadaic acid(OA).A gold electrode was firstly modified with an electropolymerized film of PTH/MB,which not only provided a stable sensing matrix with abundant amino-groups,but also improved the conductivity of the interface.Subsequently,gold nanoparticle monolayer was assembled onto the resulting surface.Making use of the unique properties of GNPs,antibodies can be self-assembled onto the surface-confined GNPs via amine-Au affinity with a high loading amount and reserve high immunological activity.Due to its ionizable carboxylic and phenolic moieties,OA could offer additional negative charge upon binding to anti-OA.After the introduction of OA,the anion forms of antibody-antigen complex formed on the sensing interface can efficiently block the electron transfer between the redox species and the electrode surface,resulting in a decrease of redox peak current.The current reduction is proportional to amount of analyte.The electrochemical characteristics of the immunosensor were studied by cyclic voltammetry(CV)，electrochemical impedance spectroscopy(EIS) and differential pulse voltammetry(DPV).The factors influencing the performance of the immunosensor were investigated.Under the optimized experimental conditions,the proposed sensing strategy provides a linear dynamic range from 0.2 μg/L to 100 μg/L and the regression equation was ΔI=1.721 7+1.083 6lgρ with a correlation coefficient of 0.992 0.The detection limit was estimated to be 0.1 μg/L.With excellent selectivity and reproducibility,the proposed immunosensor was applied in the determination of OA in real shellfish samples with spiked recoveries of 85.3%-112%.关键词：label-free electrochemical immunosensor;okadaic acid;thionine;methylene blue;gold nanoparticles
- 2263
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- 1260
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发布时间： - 摘要：A method was developed for the determination of fumonisin B1(FB1) and fumonisin B2(FB2) in cereals by high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS).The sample was extracted with methanol-water-acetic acid(74∶25∶1),and cleaned up by strong anion exchange column(SAX).FB1 and FB2 were completely separated on a ZORBAX Extend-C18 column(150 mm×2.1 mm，1.8 μm) with gradient elution by using 0.1% acetic acid water solution-acetonitrile as mobile phase,and detected by positive ion electrospray ionization mass spectrometry(ESI-MS) under select reaction monitoring(SRM) mode.The results showed that the linearities of FB1 and FB2 were in the concentration ranges of 2.5-1 000 μg/L,5.0-1 000 μg/L,respectively,with correlation coefficients of 0.999 5 and 0.999 7,respectively.The average recoveries of FB1 and FB2 from four kind of blank matries at three spiked levels of 0.02,0.50,2.00 mg/kg were in the range of 67.5%-90.5%and 70.5%-95.3%,respectively, with relative standard deviations(RSDs,n=5) of 1.3%-11.4% and 1.5%-10.6%,respectively.The limits of detection were 2.00 μg/kg for FB1and 4.00 μg/kg for FB2.This method was stable,reliable,and could be used for detection of FB1 and FB2 in cereals simultaneously.关键词：fumonisins;cereals;extract solvents;liquid chromatography-tandem mass spectrometry
- 2331
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- 1021
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发布时间： - 摘要：Manganese dioxide nanotubes possessing oxidase-like catalytic properties was synthesized by simple hydrothermal method.Influences of solution pH，temperature and catalyst dose on the catalytic performance of the nanotubes on the oxidation of 3，3'，5，5'-tetramethylbenzidine(TMB) were evaluated by measuring the UV-visible absorbance of the oxidation product of TMB.The optimum reaction conditions were as follows:concentration of manganese dioxide was 0.015 mg/mL，the reaction was conducted in pH 4.0 acetic acid-sodium acetate buffer solution at room temperature for 10 min. The influences of common metal ions on the enzyme-like catalytic performance of the manganese dioxide nanotubes were also investigated. The results indicated that lead(Ⅱ)ions revealed the most remarkable inhibition effect on the catalytic activity of manganese dioxide nanotubes. Based on this inhibition effect，a novel，highly sensitive and rapid colorimetric method for lead ions was developed.The calibration curve was linear over lead concentration in the range of 1.0×10-7-1.0×10-3 mol/L,and the detection limit was 3.0×10-8 mol/L.关键词：manganese dioxide nanotubes;hydrothermal method;enzyme mimetics;catalytic oxidation;inhibition
- 1832
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- 1038
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- 2
发布时间： - 摘要：The interaction between 2,3,3′-trichloro biphenyl(PCB-20) and human serum albumin(HSA) was investigated by molecular docking，molecular dynamics(MD) simulation，fluorescence spectroscopy，ultraviolet spectrum and synchronous fluorescence.The intrinsic fluorescence quenching of HSA by PCB-20 was a result of the formation of PCB20-HSA complex，and the quenching reasons were both static quenching and non-radiation energy transfer，which was consistent with the molecular docking.Molecular docking studies and thermodynamic analysis revealed that the binding behavior was mainly governed by hydrophobic force.MD and synchronous fluorescence revealed that HSA does have a slight conformational change when it binds with PCB-20.MD simulation also provided a support that the stability of HSA-PCB20 complex are better than that of free protein with PCB-20.Excellent agreement was found between the experimental and theoretical results.关键词：2,3,3′-trichloro biphenyl(PCB-20);HSA;molecular docking;molecular dynamics simulation;spectroscopy
- 1907
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- 1094
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- 0
发布时间： - 摘要：Low temperature enrichment coupled with GC-MS was established for the identification of fruit compounds in Nanfeng Oranges via optimization of solvent selection，frozen temperature and frozen time of sample pretreatment.The optimized conditions were as the follows:extraction solvent:n-hexane， frozen temperature:-40 ℃，frozen time:1 h.Under the optimal conditions， 64 main compounds，including esters，terpenes，alcohols and alkanes compounds were identified with the help of retention indices.Compared with the results of traditional ambient liquid-liquid extraction and reported，the established method could present a selective enrichment for substances with polarity,poor thermal stabilitiy and difficult volatility.关键词：low temperature enrichment;Nanfeng Oranges;GC-MS;retention indices;fruit compounds
- 2007
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- 998
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- 2
发布时间： - 摘要：A gas chromatographic method for the determination of pyrethroid pesticide residues(e.g.cyfluthrin，cypermethrin，deltamethrin and fenvalerate) in cabbage was developed using dispersive solid-phase extraction and dispersive liquid-liquid microextraction as sample preparation methods.The samples were extracted with acetonitrile，purified with primary secondary amine as sorbents，and concentrated into 50 μL dimethyl benzene by dispersive liquid-liquid microextraction.The analytes were analyzed by gas chromatography with electron capture detector.Factors affecting the extraction efficiency such as type and volume of extraction solvent，volume of dispersive solvent and salt effect，were investigated.Under the optimized conditions，the enrichment factors(EF)for four pyrethroid pesticides ranged from 100 to 297．The calibration curves were linear in the range of 0.01-0.1 mg/L for cyfluthrin，and 0.01-5 mg/L for the rest of targeted compounds，with correlation coefficients of 0.997 9-0.999 2.The limits of detection for cyfluthrin，cypermethrin，fenvalerate and deltamethrin were 0.03，0.02，0.01，0.01 μg/kg，and the limits of quantitation were 0.10，0.06，0.04，0. 04 μg/kg，respectively.Except of cyfluthrin,the recoveries of other three compounds at spiked levels of 0.02- 0.5 μg/g ranged from 81.9% to 93.5%，with RSDs of 9.5%-20.7%.With the advantage of quickness，low toxicity and high enrichment factors，the proposed method is applicable for the analysis of pyrethroid pesticide residues in cabbage samples.关键词：dispersive liquid-liquid microextraction;dispersive solid-phase extraction;gas chromatography;pesticide residue;cabbage
- 2160
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- 1198
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- 11
发布时间： - 摘要：A new multi-residue analytical method was developed for the determination of 27 carbamate pesticides and their metabolites residues in ginger by liquid chromatography-tandem mass spectrometry(LC-MS/MS).The samples were homogeneously extracted with acetonitrile,desalted with NaCl,and then cleaned with NH2 solid-phase extraction column.The extracts were redissolved in a mixture of acetonitrile-water(1∶1),separated on an Agilent Eclipse Plus C18 column and analyzed by LC-MS/MS under multiple reaction monitoring mode via positive electrospray ionization.The quantitation was carried out by the matrix-matched external standard calibrations.The method showed excellent linearities(r2＞099) for all compounds in a certain concentration range.The limits of detection and the limits of quantitation were in the ranges of 0.05-2.0 μg/kg and 0.2-5.0 μg/kg,respectively.The recoveries at three spiked levels of 10,30,100 μg/kg ranged from 70.9% to 119.1% with relative standard deviations of 1.0%-10.8%.The method showed the advantages of simplicity,rapidness and sensitivity,and could meet the requirements for the determination of carbamates and their metabolites residues in ginger.关键词：liquid chromatography-tandem mass spectrometry(LC-MS/MS);pesticide residue analysis;carbamates and their metabolites;ginger
- 2636
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- 1085
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- 10
发布时间： - 摘要：A novel analytical method was developed for the determination of aliphatic amines(e.g.methylamine，ethylamine and propylamine) without ultraviolet absorption by high performance liquid chromatography-indirect ultraviolet detection.Chromatographic separation was performed on a reversed-phase C18 column using 4 aminophenol hydrochloride-organic solvent as mobile phase.Effects of the background ultraviolet absorption reagents，organic solvents and 4-aminophenol hydrochloride on separation and determination of aliphatic amines were investigated.The retention rules of aliphatic amines under different chromatographic conditions were formulated.The successful separation of three aliphatic amines was achieved in 14 min by using 0.5 mmol/L 4-aminophenol hydrochloride (pH 4.0)-methanol(80∶20) as mobile phase at a flow rate of 1.0 mL/min and a column temperature of 30 ℃.The detection limits of three aliphatic amines were 0.38，0.59,0.81 mg/L，respectively.The method was successfully applied in the determination of environmental water samples with recoveries of 97.8%-99.1% and relative standard deviations no more than 1.8%.The method was simple，accurate and reliable.关键词：high performance liquid chromatography;aliphatic amine;indirect ultraviolet detection;4-aminophenol hydrochloride
- 2025
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- 1065
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- 5
发布时间： - 摘要：A liquid chromatography-tandem mass spectrometric(LC-MS/MS) method was developed for the simultaneous determination of four spice,including vanillin,methyl vanillin,ethyl vanillin and coumarin in infant formula sample.The infant formula sample was extracted by ultraphonic extraction with methanol-water(1∶1),centrifuged and diluted with water,then cleaned up with HLB solid phase extraction.The separation was performed on a Xselect HSS T3 column(150 mm×2.1 mm,3.5 μm) using a gradient elution program with mobile phase of 0.1% formic acid solution and acetonitrile.The qualitative analysis was based on retention times and characteristic ion pairs consisting of one parent ion and two fragment ions of the analyte,and the quantitative analysis was performed by the internal standard method.The results indicated that a good separation of four compounds was obtained in 7 min.The calibration curves were linear in the range of 1.0-50.0 ng?mL-1 for vanillin,and 0.5-50.0 ng?mL-1 for rest of analytes,with correlation coefficients not less than 0.999 3.The limits of quantitation(LOQs) were 10.0 μg?kg-1 for vanillin and 5.0 μg?kg-1 for methyl vanillin,ethyl vanillin and coumarin.The average recoveries at three spiked levels ranged from 85.2% to 107.4% with RSDs not more than 5.7%.This method is simple,reliable and sensitive,and is suitable for the analysis of four spices in infant formula sample.关键词：infant formula;spices;liquid chromatography-tandem mass spectrometry(LC-MS/MS)
- 2144
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- 1097
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- 3
发布时间： - 摘要：Based on the enhancement of ECL intensity of Ru(bpy)2+3 in the presence of chlorpromazine hydrochloride，a new ECL method was established for the determination of chlorpromazine hydrochloride at the glassy carbon electrode modified with composite film of graphene and nafion．Under the optimal experimental conditions，the relative ECL intensity had a good linear relationship with concentration of chlorpromazine hydrochloride in the range of 8.0×10-7 -1.2×10-4 mol/L (r=0.998 8),and the detection limit(S/N=3)was 4.0×10-7 mol/L．The RSD for 4.0×10-6 mol/L chlorpromazine hydrochloride (n=11) was 1.4%．The results indicated that the graphene/nafion modified glassy carbon electrode had a good repeatability and sensitivity.The recoveries were in the range of 93%-104%，with RSD (n=5)of 4.1%.The proposed method was applied in the analysis of chlorpromazine hydrochloride tablet with satisfactory results．关键词：graphene;modified electrode;electrochemiluminescence;chlorpromazine hydrochloride;Ru(bpy)2+3
- 2345
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- 1039
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- 8
发布时间： - 摘要：A label-free and sensitive aptasensor array for the determination of thrombin was developed based on thrombin binding aptamer(TBA) and the integrated gold film three-electrode array.A stable integrated gold film three-electrode array,including three gold working electrodes,a gold counter electrode and a thick-film Ag/AgCl reference electrode,was fabricated on FR-4 glass fiber substrate by the method of polyethylene adhesive masking and the gold sputtering technology.The aptasensor array was fabricated by self assembling thiolated TBA onto the surfaces of three gold working electrodes.The interaction between TBA and thrombin was monitored by the cyclic voltammetry and square wave voltammetry(SWV) using K3Fe(CN)6 as probe.When thrombin interacted with TBA,the current decreased due to the interference of bound thrombin with the transfer of K3Fe(CN)6.The oxidation peak current of K3Fe(CN)6 using SWV was linear in the range of 1.52-63 nmol/L for thrombin with a detection limit(S/N=3) of 0.92 nmol/L.The fabricated aptasensor array shows a high sensitivity,good selectivity and satisfactory regeneration.关键词：multielectrode;aptamer;thrombin;lable free;electrochemical biosensor
- 2193
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- 1172
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- 2
发布时间： - 摘要：The step by step seeding approach for preparation of gold nanoflowers was investigated systematically,in which 20 nm gold nanoparticles were used as the seeds and a mixture of HAuCl4 and ascorbic acid as growth solution.In this seeding approach,ascorbic acid promoted the rapid reduction of HAuCl4 and the rapid formation of small Au particles in the growth solution.The attachment of the small particles on the seed surface contributed to the growth of the nanoflowers.Ascorbic acid promoted the rapid reduction of HAuCl4 in this seeding approach.In the first two steps，the size of the seeds increased with isotropic growth,and in the last two steps,some branches on the seeds surface grew through the secondary nucleation.Finally,a uniform and controllable gold nanoflower formed by this seeding method.Gold nanoflower showed good properties on the surface enhanced fluorescence spectroscopy due to its larger surface roughness and special electromagnetic fields of the branch.关键词：gold nanoflower;seeding approach;UV-Vis spectrum;fluorescence enhancement
- 2094
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- 996
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- 4
发布时间： - 摘要：A method was developed for the determination of benzoquanmine in liquid products of milk by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).The conditions of extraction and parameters of LC-MS were optimized.The sample was enriched and purified with an LC-C18 SPE cartridge，then separated on a ZORBAX Eclipse Plus C18 column using a mixture of acetonitrile-water(15∶85) as mobile phase at a flow rate of 0.3 mL/min.The detection of benzoquanmine was performed by mass spectrometry(ESI-MS) under positive-ion electrospray ionization mode.The two precursor-product ion pairs，m/z 104.1 and m/z 146.0，were used as the quantitative and qualificative ions，respectively.The external standard method was used for quantitative analysis.The results showed that a good linearity for benzoquanmine existed in the range of 2-100 μg/L with a correlation coefficient of 0.999 1.The limits of detection(LODs) and limits of quantitation(LOQs) were 1.0 μg/kg and 3.0 μg/kg，respectively.The average recoveries of benzoquanmine at three spiked levels were in the range of 77%-105%，with relative standard deviations(RSDs) of 2.3%-5.0%.The proposed method was simple and accurate,and was suitable for the determination of benzoquanmine in liquid products of milk.关键词：benzoquanmine;high performance liquid chromatography-tandem mass spectrometry(LC-MS/MS);milk
- 2063
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- 1138
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- 2
发布时间： - 摘要：Heavy metal ion pollution has become one of the most serious environmental problems today.The development of reliable methods for the removal and determination of heavy metals in environment is of particular significance.Magnetic nanoparticles(MNPs),a new kind of nanometer-sized material,are widely used in different fields.Besides their extremely small size,high surface area,and great amount of activity sites,MNPs have the intrinsical magnetic properties which improved their unique applications in the field of separation science.Without complex centrifugation and filtration process,MNPs can be easily separated from a sample system by applying an external magnetic field.In recent years,MNPs have obtained much attention in environmental analysis,especially in treatment of heavy metal ions.In this review,the common synthetic methods developed for the preparation of MNPs,such as co-precipitation method,microemulsion method,solvothermal and thermal decomposition method are discussed.This review focuses on the applications of MNPs dealing with heavy metal ions,such as Cu(Ⅱ),Pb(Ⅱ),Cr(Ⅵ),Hg(Ⅱ),Cd(Ⅱ) and Ni(Ⅱ).Finally,the future trends and developments in this research area are prospected.关键词：magnetic nanoparticles;heavy metal ions;review
- 2026
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- 1228
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- 7
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