最新刊期
卷 30 ， 期 11 ， 2011
- 摘要：Biosensors and bioanalysis based on nanomaterials are the frontlines of current bioanalytical research.Much attention has been drawn to nanoparticles in electrochemical biosensors and bioanalysis due to their advantages of enhancing the sensitivity of the biosensors.The applications of nanomaterials in electrochemical immunosensors and DNA biosensors are reviewed.The prospects of the multi-labed nanoparticals,which have been used for biomolecular recognition and enhancing signal,are discussed emphatically for the simultaneous multianalyte detection in bioanalysis.关键词：nanomaterial;electrochemistry;biosensor;bioelectroanalysis
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发布时间： - 摘要：Optical biosensors based on different optical phenomena have been used widely over the past decade to analyse biomolecular interactions.With the advent of the nanoparticle technology,the probing of individual living cells,and the measuring of chemical species in specific locations within the cell for living cell sensing have become possible.Optical biosensors based on nanoparticles offer high sensitivity,specificity and rapid detection in the study of cancer cell or biomarker.In this paper,the applications of nanoparticles-based optical biosensor for the specific identification of molecules on the cell membrane surface for the study of cancer cells,the research of enzyme molecule in cancer cells and intracellular and the reactive oxygen,glutathione and physiological pH value in the smallest environment are reviewed.The prospect of this novel technique is also discussed.关键词：cell-based biosensors;optical detection;nanoparticles;optical probe;cancer cells
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发布时间： - 摘要：In recent years,it is of great theoretical and practical value to make a research on electrochemical biosensors.People are paying more and more attention to the preparation of biosensors based on nanomaterials,and the nano-technology has provided infinite imagination space for the development of electrochemical biosensors.Nanomaterials not only have the excellent physical,chemical and electrocatalytic properties,but also show the quantum size effect and surface effect,which can improve the electrochemical biosensors obviously to a new and high level.Therefore,the electrochemical biosensors based on nanomateirals show many excellent performances,such as smaller volume,faster speed,higher sensitivity and better stability,etc.According to their structures,the nanomaterials can be divided into three categories,e.g.zero-dimentional,one-dimensional and two-dimensional nanomaterials.In this article,the development and application of electrochemical biosensors based on following nanomaterials,zero dimensional nanoparticles（such as metal nanoparticles,quantum dots,magnetic nanoparticles,etc.）,one-dimensional nanomaterials(nanotubes,nanowires and nanorodes) and two-dimensional nanostructured thin films（like graphene） were reviewed.78 related references were cited in this review.关键词：nanomaterials;zero-dimension;one-demension;two dimension;electrochemical biosensors;development
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发布时间： - 摘要：The magnetic relaxation switches（MRS）technology based on superparamagnetic nanoparticles（SMP） and their applications in biochemical analysis were introduced in this paper.In homogenous magnetic field of miniaturized nuclear magnetic,the dispersed and aggregated states of SMP produce local inhomogeneities in the applied magnetic field,resulting in the decrease or increase in the spin ± spin relaxation time（T2） of surrounding water molecules,which is called magnetic relaxation time（MRS） sensing effect.The magnetic particles binding with specific molecules can act as magnetic relaxation switches（MRS） when they coupled specially with target analytes.In MRS assays,the presence of an analyte causes the particles to transition between dispersed and clustered states and affects the T2 relaxation times of surrounding water molecules.Compared with the conventional immunological methods,MRS assay is more sensitive,simple and time-saving due to its combination of nanobiotechnology,nuclear magnetic resonance and immunoassay.Predictably,it has a remarkable application potential in the fields of medical diagnosis,environmental monitoring,food safety analysis,public healthy security and molecular interactions study,etc.关键词：superparamagnetic particle（SMP）;magnetic relaxation switches（MRS）;nano biological sensing;biochemical analysis
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发布时间： - 摘要：In pH 7.0 phosphate buffer solution，HAuCl4 was reduced by 3，5-dihydroxybenzonic acid（DBA） to form nanogold particles that exhibited a strong resonance scattering（RS） peak at 610 nm.However，in the presence of malemine（MA）， DBA would not reduce HAuCl4 but react with MA to form a stable complex by means of polyhydrogen bonds，which could result in the decrease of RS intensity.The decreased RS intensity was proportional to the MA concentration.Based on this，a RS method was developed for the detection of MA.Under the optimal conditions，the calibration curve was linear in the range of 5.0×10-6-4.0×10-5 mol?L-1 with correlation coefficient of 0.996 8.The method was applied in the determination of MA in milk with satisfactory result.关键词：malemine;polyhydrogen bonds complex;nanogold;resonance scattering method
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发布时间： - 摘要：An electrochemical sensing platform was developed based on the composite of ionic liquid（1-butyl-3-methylimidazolium dicyanamide,［BMIM］N（CN）2，IL）,multi-walled carbon nanotubes（MWCNTs） and polymeric matrix（chitosan,CS）.Scanning electron microscope images showed that MWCNTs had a good dispersibility in the MWCNTs-IL-CS composite and formed a relative smooth film with unique structure.Electrochemical studies indicated that the MWCNTs-IL-CS composite provided a synergistic improvement on the electrochemical oxidation of dopamine（DA）,uric acid（UA） and ascorbic acid（AA） by the decrease of their anodic over-potentials and the enhancement of their amperometric responses.The peak separations between UA and DA,DA and AA were 114 mV and 208 mV,respectively.Additionally,the MWCNTs-IL-CS composite modified glassy carbon electrode（MWCNTs-IL-CS/GCE） showed a good analytical performance in the simultaneous determination of DA,AA and UA.The calibration curves of 5.00-425 μmol/L,0.020-2.25 mmol/L and 0.050-10.0 mmol/L,and the detection limits（S/N=3） of 1.01,10.7 and 42.9 μmol/L were obtained for DA,AA and UA,respectively.With good selectivity and sensitivity,the present method is promising in the simultaneous determination of DA,AA and UA in real samples.关键词：ionic liquid;multi-walled carbon nanotube;chitosan;simultaneous voltammetric determination;dopamine
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发布时间： - 摘要：Water-soluble CdSe quantum dots（QDs） were synthesized in aqueous solution with thioglycollic acid as stabilizer.By using CdSe QDs as fluorescent probe,based on the enhancement of the fluorescence intensity of CdSe QDs by glycyrrhizin（GL）,a simple,rapid and sensitive method for the determination of GL was proposed and validated.Forthermore,the possible mechanism of interaction between CdSe QDs and GL was discussed.Effects of experimental conditions were investigated.The optimal conditions were as follows:buffer:pH 7.4 Na2HPO4-NaH2PO4 solution,concentration of quantum dots:2.4×10-4 mol/L,reaction time:10 min.Under the optimal conditions,a good linearity was obtained between fluorescence intensity and GL concentration in the range of 5.0×10-9-1.0×10-7 g/L with a correlation coefficient of 0.998 0.The obtained linear regression equation was:IF/I0F=1.337+0.014ρ（10-9 g/L） and the limit of detection was 4.8×10-9 g/L.The proposed method was successfully applied in the determination of GL in actual samples,and the results were in good agreement with that of the national standard method in Chinese Pharmacopoeia.The study indicated that the combination of QDs and GL produced a nice labelling effect,and it would be of considerable significance to the further investigation of GL targeted carrier system.关键词：CdSe quantum dots;glycyrrhizin;fluorescence enhancement
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发布时间： - 摘要：A method for measuring particle size distribution，density and concentration of nanometer suspension was proposed，and the measurement apparatus and system was designed.Meanwhile,the pulse echo mode was adopted to measure the attenuation spectrum of nano-antimony tin oxide（ATO）suspension at high frequencies.A wide-band ultrasonic transducer with a center frequency of 25 MHz（V324-SU，OLYMPUS） served as an emitter and a receiver simultaneously in the experiments.Then it can yield an ultrasonic spectrum over the frequency from 17 MHz to 26 MHz.The optimum regularization algorithm was applied to minimize the influence of ill-conditioned equation during the inversion of particle size distribution.The recovered median size D50 of nano-ATO was 22.07 nm which was in agreement with that of the sedimentation method with the error no more than 0.1%.At the same time，the multiple reflection approach was employed to obtain the ultrasonic impedance of the nanometer suspension.Several groups of superb ultrasonic signals consisting of more than 12 pluse-echoes in each one，were acquired with the same ultrasonic transducer.The ultrasonic velocity，overall density and concentration of the aqueous ATO suspensions can be determined based on the mathematical derivation and acoustic theory.Experimental results showed that the error of density and concentration was within 0.6% and 8%,respectively.Due to its avantages of reliable principle,simple apparatus and time-saving，the proposed method could provide an online monitoring for the particle size,density and concentration of nano-particle materials during the processing and preparation.关键词：ultrasound;two-phase flow;multi-parameter;particle size;concentration and density
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- 1
发布时间： - 摘要：Under ordinary pressure，3-D flower-like ZnO nanomaterials were successfully synthesized by two steps of sol-gel and chemical solution growth methods with three different substrates.The samples were characterized by means of X-ray diffraction（XRD）,scanning electron microscopy（SEM），transmission electron microscopy（TEM），selected-area electron diffraction（SAED），ultraviolet absorption spectroscopy and photoluminescence spectrum（PL）.The results indicated that the component units of flower-like ZnO were ZnO nanorods grown along the c-axis.The diameter and length of nanorods were approximately 100 nm and 2 μm,respectively.Different substrates had little effect on the morphology of flower-like ZnO and the solution pH value had great influence on the formation of flower-like ZnO.The ultraviolet absorption spectrum and photoluminescence spectrum of 3-D flower-like ZnO nanomaterials indicated that the nanomaterials produced a strong broadband absorption in ultraviolet area，a strong blue emission at 421 nm and two weak green emissions at 520 nm and 560 nm.Therefore，this flower-like ZnO could be used to make the blue light emitting devices.关键词：flower-like;ZnO;nanorod;photoluminescence spectrum
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发布时间： - 摘要：An electrochemical sensor based on graphene sheets（GS） and gold nano-particles（Au） composite nano-particles modified screen-printed carbon electrodes（SPCEs） was fabricated（SPCEs│GS/Au）,and an electrochemical method was developed for the determination of trace cadmium（Cd） in water by differential pulse stripping voltammetric（DPSV）method.Au preparation and the construction processes of SPCEs│GS/Au electrode were characterized by scanning electron micrography（SEM）,and the electrochemical properties of Cd2+ were investigated.Under the optimum conditions,a good linear relationship was obtained between peak current and Cd2+ concentration in the range of 2.5×10-7-2.5×10-5 g/L（r2=0.998 0） with a detection limit（3σ） of 1.8×10-7 g/L.The method was applied in the determination of Cd2+ concentration in real water samples with recoveries of 96%-107%.The analytical results were consistent with those of the graphite furnace atomic absorption spectrometric（GF-AAS） method.The SPCEs│GS/Au electrode showed a high response current and an enrichment ability due to the modification of composite nano-particles.Therefore,the electrode was suitable for the determination of Cd2+ in water with advantages of disposable design,little sample consumption and simple operation.关键词：graphene sheets;gold nano-particles;screen-printed carbon electrode;differential pulse stripping voltammetry;cadmium
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发布时间： - 摘要：Nano B2O3/TiO2 composite as a new sorbent was synthesized， and the characteristic of the synthesized material was studied by scanning electron microscope（SEM） and infrared spectrometry （IR）. By investigating the optimal conditions of adsorption and desorption of nano B2O3/TiO2 composite for Ag+， a new method for the determination of trace silver was proposed. After oscillated for 20 minutes at 22 ℃ and pH 4.3， silver could be quantitatively adsorbed by nano B2O3/TiO2 composite， and the adsorption capacity was obtained to be 11.72 mg/g. The adsorbed silver could be eluted from the surface of the absorbent with 0.1 mol/L HNO3-0.05 mol/L thiourea（1∶4）. Under the optimum experimental conditions， the calibration curve was linear over Ag+ concentration in the range of 0.01-4.00 mg/L， with a detection limit（3σ） of 2.01 μg/L.The RSD（n=11） for determination of 0.4 mg/L Ag+ was 1.8%. The spiked recoveries ranged from 95% to 105%. The method was applied in the determination of trace silver in slag samples with satisfactory results.关键词：nano B2O3/TiO2 composite;separation and preconcentration;flame atomic absorption spectrometry（FAAS）;silver
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发布时间： - 摘要：A new ［BMIM］PF6-GR-CHIT/GCE modified electrode was fabricated via the film formed by chitosan（CHIT）,and using graphene（GR）and ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate（［BMIM］PF6） as modifiers.In 0.1 mol/L PBS solution,the electrochemical behavior of p-aminophenol（PAP） at ［BMIM］PF6-GR-CHIT/GCE was investigated by cyclic voltammetry and differential pulse voltammetric method.The cyclic voltammetric curve of PAP at the ［BMIM］PF6-GR-CHIT/GCE electrode presented a pair of sensitive and reversible redox peaks.The peak current response at the proposed electrode was enhanced 2.2 folds as high as that at the GR-CHIT/GCE,and the peak potential difference was 0.045 V.The differential pulse voltammetric peak current of PAP at ［BMIM］PF6-GR-CHIT/GCE showed a good linear relationship in the concentration range of 5.0×10-6-5.0×10-4 mol/L,with a detection limit（S/N=3） of 3.0×10-7 mol/L.The method was used in the determination of p-aminophenol in water sample with satisfactory result．关键词：graphene;［BMIM］PF6;p-aminophenol;cyclic voltammetry;differential pulse voltammetry
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发布时间： - 摘要：ZnS nanoparticles was synthesized using zinc acetate and sodium sulfide as starting materials in water solution.The morphology and crystal phase of nano-ZnS were characterized by transmission electron microscopy（TEM） and powder X-ray diffraction（XRD）.The interaction of nanoparticles and bovine serum albumin（BSA） was investigated by fluorescence spectroscopy in pH 7.0 Tris-HCl buffer.The result showed that the interaction between BSA and ZnS nanoparticles could resulted in the endogenous fluorescence quenching of BSA,which belonged to a static quenching mechanism.The quenching rate constant was 1.88×1014 L?mol-1?s-1,the binding constant（Ka） and binding site（n） were 1.73×105 L?mol-1 and 0.83,respectively.关键词：Nano-ZnS;bovine serum albumin（BSA）;fluorescence spectroscopy;interaction;static quenching
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发布时间： - 摘要：A feasible approach for the analysis and identification of the complex components in mixed flavor was developed by moving window characteristic peak orthogonal projections resolution algorithm,GC-MS and the flavor database established.The analysis process was as follows:the compositions of mixed flavors containing five essential oils and three tinctures in unknown complex essence were firstly analyzed by GC-MS,and then moving window characteristic peak orthogonal projections resolution algorithm combined with the flavor database established was employed to distinguish the essential oils and tinctures in mixed flavors.Finally,the parameters related to the algorithm and the factors influencing the qualitative results were discussed in detail.The five essential oils and the three tinctures which were mixed into unknown complex essence were distinguished accurately by the presented method,and the obtained results indicated that the proposed approach was indeed a very effective and promising way for the analysis of complex components in mixed flavors.关键词：mixed flavors;moving window orthogonal projections resolution algorithm;GC-MS;flavor database;complex component analysis
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发布时间： - 摘要：Melamine was employed as an analogue template to prepare a molecularly imprinted monolithic column which presents the ability of selective recognition to trimethoprim（TMP） because of the similarity between melamine molecule and substructure of trimethoprim.Methacrylic acid was applied as a functional monomer and ethylene glycol dimethacrylate as a cross linker during the in-situ polymerization process.Under the optimal conditions,the imprinted monolithic column showed a selective recognition to TMP when using methanol-water（70∶30,by volume） as mobile phase,but not to other structurally similar compounds such as folic acid and methotrexate,et al.Melamine would not disturb the determination of TMP.The MIP monolithic column was applied in the determination of TMP in sulfamethoxazole and human serum.The result indicated that,for sulfamethoxazole,the linear range of TMP was in the range of 5.05-101 mg/L（r=0.999 6）,and the recoveries at two spiked concentrations of 37.9 mg/L and 50.5 mg/L were 104% and 90%,respectively.For human serum sample,the linear range of TMP was in the range of 5.05-60.7 mg/L（r=0.999 6）,and the recoveries of TMP at two spiked concentrations of 25.3 mg/L and 50.5 mg/L were 95% and 97%,respectively.关键词：trimethoprim;analogue template;molecularly imprinted polymer;monolithic column;HPLC
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发布时间： - 摘要：In alkaline conditions,4-（ 3-acryloxy-2-hydroxy ） propyloxy-β-cyclodextrin（ PCD ） was synthesized based on the reaction of 1-alklyloxy-2,3-epoxy propane（also named as allyl glycidyl ether,AGE） and β-cyclodextrin（β-CD）.A new type β-cyclodextrin polymer chiral monolithic column for CEC was prepared by using the in-situ polymerization of PCD and GMA as functional monomers in the capillary tube.The prepared monolithic column was evaluated by separating racemic mixtures of three amino acids and a chial drug（guguaifenesin） in capillary electrochromatography mode.The influences of organic modifier，buffer pH value and temperature on separation were investigated.Under the optimal CEC conditions,all of enantiomers were baseline separated in 8 min.Results showed that the novel PCD monolithic column had good chiral recognition ability,better reproducibility and easy operation.关键词：monolithic column;capillary electrochromatography(CEC);allyl glycidyl ether β-CD;DL-amino acid;enantiomer separation
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发布时间： - 摘要：A sensitive ultra-performance liquid chromatography-electrospray tandem mass spectrometric method（UPLC-MS/MS） combined with solid phase extraction（SPE） was established for the determination of eighteen steroid hormones，including prednisolone，prednisone，methylprednisolone，betamethasone，dexamethasone，trenbolone，prednisolone acetate，hydrocortisone acetate，nortestosterone，testosterone，stanozolol，norethindrone，hydroxyprogesterone，methyltestosterone，androstenedione，megestrol acetate，progesterone and medroxyprogesterone acetate in the influent and final effluent from wastewater treatment plant（WWTP）.The operation conditions influencing the SPE performance were optimized by single factor experiments and orthogonal test，and UPLC-MS/MS experimental parameters were also studied in detail.The results indicated that，under the optimal conditions， the calibration curves of eighteen steroid hormones were linear in the range of 1.0-200 μg?L-1 with their correlation coefficients（r2） not less than 0.997 6.The detection limits for the method ranged from 1.49 ng?L-1 to 10.59 ng?L-1.The recoveries of WWTP water samples at spiked levels of 20-100 ng?L-1 were between 67% and 109% with RSDs not more than 13.9%.The method was applied in the determination of steroid hormones in wastewater from four sewage treatment plants in Nanjing.Nortestosterone，androstenedione，testosterone，hydroxyprogesterone，prednisone and prednisolone were found in the influent of the four sewage treatment plants，in which the concentration of prednisone was the highest.A certain amount of steroid hormones were also found in the final effluent.关键词：steroid hormones;wastewater treatment plant;SPE;UPLC-MS/MS
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发布时间： - 摘要：An ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometric（UPLC-ESI MS/MS） method was developed for the simultaneous determination of six benzodiazepines,including diazepam,oxazepam,nitrazepam,triazolam,estazolam and midazoalm,in animal feeds.The benzodiazepines in the feeds were extracted with alkaline tert-butyl methyl ether followed by clean-up with Oasis MCX cartridge.The LC separation was performed on a Waters Acquity UPLC BEH C18 column（50 mm×2.1 mm,1.7 μm） by gradient elution using 0.1% formic acid and acetonitrile as mobile phase at a flow rate of 0.3 mL/min.The identification of six drugs was achieved by electrospray ionization tandem mass spectrometer under multiple reaction monitoring（MRM） mode and the quantification analysis was performed by the external standard method.The calibration curves showed good linearities in the range of 5-100 μg/L.The limits of detection（LOD） for the six drugs in feeds were 2 μg/kg and the limits of quantitation（LOQ） were 5 μg/kg.The average recoveries of the six drugs at three spiked levels of 5,20,100 μg/kg were between 68% and 94% with RSDs of 5.8%-127%.The method was rapid,accurate and sensitive,and could be applicable in the routine assay on benzodiazepines in animal feeds.关键词：benzodiazepines;ultra-performance liquid chromatography-tandem mass spectrometry;feeds
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发布时间： - 摘要：The electrochemical behavior of salicylic acid(SA) on an electro-activated glassy carbon electrode(EGCE) was studied by cyclic voltammetry(CV) and differential pulse voltammetry(DPV).The glassy carbon electrode(GCE) was activated in pH 7.0 PBS buffer for 400 s by potentiostatic method at+1.7 V.In 0.2 mol?L-1 NaOH solution,a well-defined oxidative peak of SA was observed at 0.602 V(vs.Ag/AgCl) on the activated electrode.The anodic peak current increased linearly with scan rate from 0.02 V?s-1 to 0.2 V?s-1,revealing that the reaction was a absorption-controlled process.The experimental parameters were optimized and the correlation between peak current(Ipa) and concentration was studied by differential pulse voltammetry.Under the optimal conditions,the linear range for SA was in the range of 5.0×10-6-2.0×10-3 mol?L-1 with a correlation coefficient of 0.986 3,and the detection limit(S/N=3) was 1.2×10-7 mol?L-1.The activated glassy carbon electrode showed the advantages of simple preparation procedure and good reproducibility,and was applied in the determination of salicylic acid in pharmaceutical drugs with satisfactory results.关键词：salicylic acid;electro-activated glassy carbon electrode;differential pulse voltammetry
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- 1
发布时间： -
Determination of Phenylalanine in Beverage by Using the Cu（Ⅱ）catalyzed Oscillating Chemical Reaction
摘要：The effects of D- and L-phenylalanine on the Cu（Ⅱ） catalyzed oscillating chemical reaction in an alkaline medium were investigated in this paper.The results showed that the changes of amplitude（ΔA） after adding D- and L-phenylalanine were different.The changes of the amplitude were linearly proportional to the negative logarithm concentration of D-phenylalanine in the range of 1.80×10-9-1.40×10-4 mol?L-1（r=0.996 3） with detection limit（LOD） of 2.69×10-11 mol?L-1,and for L-phenylalanine in the range of 1.80×10-6-1.80×10-4 mol?L-1（r=0.995 8） with detection limit of 2.61×10-7 mol?L-1.The proposed method was successfully used for the determination of L-phenylalanine in beverage and simulating water sample.The possible reaction mechanism was also discussed.关键词：phenylalanine;oscillating chemical reaction;beverage;determination- 2911
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发布时间： - 摘要：A novel enantioseparation method for amlodipine by high performance capillary electrophoresis with capacitively coupled contactless conductivity detection（C4D） using binary chiral selectors was developed.The enantiomers of amlodipine were baseline separated in 20 min with an uncoated fused silica capillary（50 μm i.d.×45 cm，leff=40 cm） under the following optimum conditions：18 mmol/L citric acid+6 mmol/L NH3?H2O+12 mg/L hydroxypropyl methyl cellulose（HPMC）+35 mmol/L hydroxypropyl-β-cyclodextrin（HP-β-CD）as background electrolyte,separation voltage:+15 kV,injection voltage:13 kV,injection time:10 s.The calibration curve of the enantiomers showed a good linearity in the range of 2.0-40 mg/L with correlation coefficient more than 0.995.The detection limit of the enantiomers was 0.5 mg/L.Effects of several factors on resolutions,such as composition of running buffer,pH value,separation voltage and injection method,were investigated.The efficacy of the HP-β-CD and HPMC were discussed.The results indicated that the proposed method was simple,low cost,rapid and reproducible,and was successfully applied to monitor the enantiomers of amlodipine in the commercial amlodipine tablets and levoamlodipine tablets.关键词：capacitively coupled contactless conductivity detection;capillary electrophoresis;chiral drugs analysis;binary chiral selectors;amlodipine
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发布时间： - 摘要：A high performance liquid chromatographic method was established for the simultaneous determination of 5 classes of antibiotics such as chloramphenicols,nitromidazoles,quinolones,sulfonamides and tetracyclines including 15 antibiotics residues in honey.The honey sample was dissolved in phosphoric acid solution at pH 2.0 and then purified and enriched directly with PCX solid phase extraction small column.The target compounds were separated on HPLC using acetonitrile-phosphoric acid solution（pH 2.5） as mobile phase by gradient elution,and detected with ultraviolet detector at 274 nm and 315 nm.The calibration curves of 15 antibiotics（chloramphenicol,metronidazole,ornidazole,oxytetracycline,chlorotetracycline,doxycycline,sulfapyridine,ciprofloxacin,lomefloxacin,ofloxacin,gatifloxacin,sparfloxacin,sulfadiazine,sulfamerazine,sulfamethoxazole） were linear in the range of 0.2-20.0 mg/L.The average spiked recoveries ranged from 60% to 105% with relative standard deviations of 1.3%-6.9%.The limits of detection of this method were in the range of 9.70-12.54 μg/kg and the limits of quantitation were 32.34-41.80 μg/kg.The method showed the advantages of simple sample preparation,good selectivity and high sensitivity,and was suitable for the simultaneous determination of antibiotics in honey.关键词：solid phase extraction;high performance liquid chromatography;antibiotics;honey;multi residues
- 1997
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- 1071
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- 6
发布时间： - 摘要：A method for the determination of seven trace inorganic anions（F-，NO-2，Cl-，Br-，NO-3，PO3-4，SO2-4） on the surface of printed circuit board（PCB） was established by ion chromatography combing with microwave preconcentration.The PCB samples were extracted by water,and preconcentrated with microwave oven.The IC separation was carried out on Ionpac AS23 analytical column using 4.5 mmol/L Na2CO3-0.8 mmol/L NaHCO3 as mobile phase at constant flow rate of 1.0 mL/min.Under the optimal conditions,seven anions were successfully separated within 23 min.The calibration curves of F-，NO-2，Cl-，Br-，NO-3，PO3-4，SO2-4 were linear in the ranges of 20-200,50-500,50-500,100-400,50-500,200-800, 50-500 μg/L,respectively.Their detection limits（S/N=3） ranged from 0.5 μg/L to 2.4 μg/L.The spiked recoveries were between 86% and 105%with relative standard deviations（RSDs） less than 5.0%.The method was simple,rapid,sensitive and reliable,and was suitable for the simultaneous determination of seven anions on the PCB.关键词：microwave preconcentration;ion chromatography;printed circuit board;inorganic anions
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发布时间：
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