最新刊期
卷 32 ， 期 11 ， 2013
- 摘要：In view of the detection of trace impurity elements in gutter oils,a gas chromatography-mass spectrometric(GC-MS) method was proposed for the analysis of the chemical compositions in condiment.The experimental results revealed that acetic acid derives from vinegar,3-butene nitrile from pickles sauce,allyisothiocyanate from mustard,furfural derived from soy sauce,anethole from star anise and zingiberene from ginger.Eat hutch waste oil could be identified by confirming the existance of these characteristic compositions in oil samples.In this paper,headspace solid phase microextraction(SPME) was applied to enrich the trace exogenous impurity elements,and a dedicated gas chromatographic column was also developed.Six-ingredients,including acetic acid,3-butene nitrile,furfural,allyisothiocyanate,anethole and zingiberene were determined by this GC-MS technique.If one or more these trace elements were detected in the sample,it could be identified as eat hutch waste oil.关键词：solid-phase microextraction(SPME);gas-chromatography-mass spectrometry(GC-MS);gutter oils;eat hutch waste oil;characteristic compositions;condiments;identification
- 3005
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- 1133
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- 6
发布时间： - 摘要：Based on the fact that 6-propy-2-thiouracile（PTU） could strongly enhance the electrochemiluminescence（ECL） of tris（2,2’-bipyridine） ruthenium（Ⅱ）（Ru（bpy）2+3）,a new flow injection analysis method with a homemade electrochemiluminescence（FI-ECL） detector was proposed for the first time.The experimental parameters those may influence the ECL intensity of the Ru（bpy）2+3/PTU system（such as voltage signal mode and applied potential,pH of buffer solution,flow rate of the carrier solution,and concentration of Ru（bpy）2+3solution ） were investigated.The optimum conditions for the FI-ECL detection of PTU were obtained and the possible mechanism of the ECL system was suggested.The results showed that in 0.1 mol?L-1 pH 12.0 H3PO4-NaOH buffer solution,when the carrier solution’s flow rate was setted at 1.5 mL?min-1,the strongest ECL intensity enhancement could be realized at potential of +1.50 V in the present of 1.0×10-4 mol/L Ru（bpy）2+3.Under this optimal condition,the linear range of PTU was 2.0×10-7-1.0×10-4 mol/L with a correlation coefficient of 0.998 6 and a detection limit(S/N=3) of 1.3×10-8 mol/L.The relative standard deviation（RSD,n=3） for 1.0×10-6 mol/L PTU standard solution was 1.2%.The method was simple,rapid and sensitive,and was successfully applied in the determination of PTU in spiked animal feeds.关键词：flow-injection;electrochemiluminescence;6-propy-2-thiouracile;tris（2,2’-bipyridine） ruthenium（Ⅱ）
- 2023
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- 1028
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- 2
发布时间： - 摘要：A method was developed for the determination of 12 kinds of estrogenic and progesterone hormones in infant formula milk powder using ultra fast liquid chromatography-ion trap-time of flight mass spectrometry（UFLC-IT-TOF-MS）.The milk powder was dissolved in warm water,and extracted with ethyl acetate after enzymatic hydrolysis.The extract was cleaned up on an HLB cartridge.The estrogenic and progesterone hormones were separated on Shim pack XR-ODSⅡand HSS T3 columns,and then analyzed in ESI- mode for estrogens and ESI+ mode for progesterones.The calibration curves of the target compounds were linear in the range of 1.0-200 μg/L with correlation coefficients greater than 0.998.The average spiked recoveries were in the range of 79.9%-110.4% with relative standard deviations of 2.8%-8.0%.The limits of detection（LODs） ranged from 0.3 μg/kg to 0.6 μg/kg and the limits of quantitation（LOQ） ranged from 0.9 μg/kg to 1.8 μg/kg.The mass errors between theoretical and experimental masses were obtained for deprotonated molecule of 12 estrogenic and progesterone hormones,and the main possible fragmentation pathway of estrone was verified.关键词：ultra fast liquid chromatography-ion trap-time of flight mass spectrometry（UFLC-IT-TOF-MS）;estrogenic and progesterone hormones;infant formula milk powder
- 2008
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- 982
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- 4
发布时间： - 摘要：Copper hexacyanoferrate(CuHCF) redox probes were fabricated on the gold electrode surface through electrodeposition.Through the strong interaction of Au-CN bond between CN-(CuHCF) and gold nanoparticles(GNPs)，GNPs were assembled on the CuHCF modified electrode.Then，thiolated adenosine aptamers(APT) was assembled on the electrode surface with Au-S bond for the fabrication of highly sensitive label-free aptamer biosensor used for the determination of adenosine(AD).Electrochemical impedance spectroscopy was used to monitor the self assembly process of the aptamer biosensor.The electrochemical behavior of the aptamer biosensor was studied by cyclic voltammetry(CV) and differential pulse voltammetry(DPV).Effects of the supporting electrolytes and scan rates on the response of aptamer biosensor were investigated.The biosensor showed a good linear relationship for adenosine in the range of 100 fg/mL-50.0 ng/mL，with a correlation coefficient(r) of 0.998 and a detection limit of 45.0 fg/mL.关键词：copper hexacyanoferrate;gold nanoparticles;aptamer biosensor;adenosine
- 2152
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- 1243
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- 3
发布时间： - 摘要：Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF MS） was used to analyze the end-group distribution of poly（p-phenylene terephthalamide）（PPTA）.Samples were prepared by the evaporation-grinding（E-G） method.In order to improve the grinding of PPTA，the samples were treated with concentrated sulfuric acid until they became soft before the sample preparation.3-Aminoquinoline was employed as the matrix material with potassium trifluoroacetate as the cationizing agent.The ratio of matrix-to-polymer was optimized in order to achieve higher signal-to-noise ratio.The MALDI-TOF MS spectrum of the sample with residual sulfuric acid was compared with the MS spectra of the sample without residual sulfuric acid，the influence of residual traces of sulfuric acid on the MALDI-TOF MS spectra was analyzed.The results showed that a relatively higher signal-to-noise ratio was obtained at the matrix-to-polymer mixing ratio of 20∶1 in the reflection mode.The peak splitting from hydrogen/sodium and hydrogen/potassium exchange，the amino-group fragment loss and decarboxylation probability were also reduced by the residual traces of sulfuric acid in the samples，which could improve the signal-to-noise ratio and reliability.关键词：poly（p-phenylene terephthalamide）;end-group distribution;MALDI-TOF MS;matrix-to-polymer ratio;residual traces of sulfuric acid
- 1853
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- 912
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- 0
发布时间： - 摘要：A gas chromatographic method was established for the simultaneous determination of 20 kinds of organophosphorus pesticide residues，including dichlorvos，methamidophos，acephate，cadusafos，phorate，omethoate，fonofos，dimethoate，pirimiphos-methyl，chlorpyrifos，malathion，fenthion，isofenphos methyl，fenitrothion，parathion，isocarbophos，profenofos，fenamiphos，triazophos and pyridaphenthion，in Fruit traditional Chinese medicines(Dried tangerine peel，Foeniculum vulgare，Jave amonum fruit，Fructus arctii，Lycium chinense，Dried red dates).The factors affecting the extraction，purification，detection efficiency were optimized，and the optimal conditions were as the following:the samples were extracted with ethyl acetate，and the elution fractions of gel permeation chromatography was collected at 9-15 min，then purified with ENVI-Carb solid phase extraction column.The separation of target compounds were performed on a film thickness of DB-1701 capillary column(30 m×0.25 mm×0.25 μm)，and the quantitative analysis of organophosphorus pesticides was carried out by gas chromatography with flame photometric detector and the external standard method.Under the optimized conditions，the calibration curves of 20 organophosphorus pesticides were linear in the range of 0.01-2.0 mg/L with correlation coefficients of 0.996 6- 0.999 5.The detection limits(S/N=3) were in the range of 0.66-5.78 μg/kg.The recoveries of the pesticides in various Fruit traditional Chinese medicines at three spiked levels ranged from 80.2% to 109.9%，with relative standard deviations of 2.3%-13%.With the advantages of easy operation，accuracy and sensitivity，the method is applicable in the simultaneous determination of 20 kinds of organophosphorus pesticide residues in Fruit traditional Chinese medicines.关键词：organophosphorus;pesticide residues;gel permeation chromatography;solid phase extraction;gas chromatography;Fruit traditional Chinese medicines
- 2081
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- 1082
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- 11
发布时间： -
Study on the Analysis Methods and Distribution of Basic Nitrogen Compounds in Coal Liquefaction Oils
摘要：Basic nitrogen compounds in coal liquefaction oil were extracted by acid extraction method and analyzed by gas chromatography-mass spectrometry（GC-MS）and gas chromatography-nitrogen chemiluminescence detection（GC-NCD）.It can be seen from the analysis that basic nitrogen compounds were clean separated out from the oil sample through acid extraction.38 kinds of basic nitrogen compounds in the full range of coal liquefied oil were determined by GC-MS,and they were mostly pyridine class,aniline class and quinoline class.18 kinds of basic nitrogen compounds were quantified by GC/NCD and the content accounted for 88.9% of total basic nitrogen compounds,in which the pyridine class accounted for 24.48% of total basic nitrogen compounds,aniline class accounted for 37.98%,and quinoline class accounted for 26.48%.关键词：coal liquefaction oils;nitrogen compounds;liquid-liquid extraction- 1864
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- 1020
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- 4
发布时间： - 摘要：Using pig collagen and titanium sulfate as raw material，by tanning reaction with high temperature calcination，the nanometer titanium dioxide was prepared.Then，fixing the nanometer titanium dioxide-chitosan（Cs） nanocomposites on gold electrodes through electrostatic adsorption，using abundant amino in Cs to absorb gold nano particles and lastly absorb alpha-fetoprotein antibodies,an AFP immunosensor was successfully fabricated.The techniques of UV-vis spectroscopy(UV-Vis)，infrared spectroscopy(FT-IR)，X ray diffraction(XRD) and transmission electron microscopy were used to characterize the nanometer titanium dioxide.Under the optimal conditions，the immune sensor showed a good linear relationship for AFP in the range of 0.01-100 ng/mL，with a correlation coefficient of 0.998 2 and a detection limit of 0.003 ng/mL.关键词：collagen;stencil;nano titanium dioxide;chitosan;gold nanoparticles;α-fetoprotein(AFP);immunosensor
- 1768
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- 955
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- 5
发布时间： - 摘要：A rapid analytical method based on C18 solid phase extraction disk followed by high performance liquid chromatography(HPLC) for the determination of six trace sulfonylurea herbicides,including tribenuron,metsulfuron-methyl,chlorsulfuron,bensulfuron-methyl,ethametsulfuron,chlorimuron-ethyl in water was developed.Chromatographic conditions were optimized，and the factors that influence the extraction,including type and volume of desorption solvent,pH value of sample and amount of salt addition were investigated.Experimental results showed that,the extraction efficiencies for 6 sulfonylurea herbicides in water were the highest by C18 SPE disk adsorption when the water samples were adjusted to pH 3.0,and the target compounds adsorped on C18 were eluted with 10 mL of methanol.Under the optimal conditions,good linear relationships(r2≥0.999 0) were obtained between peak areas and concentrations of 6 sulfonylurea herbicides in the ranges of 0.10-20.0 μg/L for tribenuron and 0.05-20 μg/L for the rest of the target compounds.The detection limits were in the range of 0.019-0.037 μg/L.The recoveries of 6 sulfonylurea herbicides in spiked water sample and seawater sample were in the ranges of 92.6%-105.7% and 89.8%-108.7%,with relative standard deviations (RSDs) of 0.7%-7.1% and 0.5%-4.0%,respectively.The method was simple,rapid,accurate and sensitive,and could provide a new option for the determination of sulfonylurea herbicides in environmental water.关键词：solid phase extraction disk;high performance liquid chromatography(HPLC);sulfonylurea herbicides;surface water;seawater
- 2018
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- 1124
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- 5
发布时间： - 摘要：In this paper,the silver nanoparticles were prepared through green chemical reduction of silver sulfate in the liquid phase using vitamin E(VE) as a reducing agent,and starch as a stabilizer.Yellow silver nanoparticles with different sizes were obtained by changing pH value of solution and reaction time.The silver nanoparticles were characterized by transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR),ultraviolet-visible spectroscopy(UV-vis),scanning electron microscopy(SEM) and electrochemical method.The results indicated that VE molecules in the solution were oxidized to benzoquinone,and the synthesized silver nanoparticles were spherical with a diameter range of 8-25 nm.And in strong alkaline condition,the silver nanoparticles were smaller,distributing more uniformly with an average diameter of about 10 nm.The strong absorption bands at 417,411,409,408 nm appeared in the UV-vis spectra for different silver particle solutions,which could attribute to the excitation of surface plasmons in the nanoparticles.The silver nanoparticles also exhibited excellent electrochemical property and good electrocatalytic activity for the electrochemical behavior of L-cysteine.关键词：silver nanoparticles;vitamin E;green reduction;characterization
- 2635
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- 1094
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- 3
发布时间： - 摘要：The azo benzene(Azo) doped polyvinylpyrrolidone(PVP) composite film was immobilized on the surface of potassium ion(K+) exchanged glass optical waveguide(OWG) by spin coating method.An Azo-PVP compound thin film/K+ exchange glass optical waveguide gas sensor was developed and its gas sensibility was investigated.The experimental results showed that the present gas sensor has a good sensibility to low concentration of styrene vapor at room temperature,and its response time and recovery time for 1.0×10-8 volume fraction of styrene gas were 9 s and 24 s,respectively.A good linear relationship was obtained between the output light intensity and volume concentration in the range of 1.0×10-8-1.0×10-3.The Azo-PVP composite film optical waveguide gas sensor has a short response time,high sensitivity,simple structure and easy farication.关键词：optical waveguide gas sensor;PVP;azo benzene;styrene
- 1974
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- 933
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- 2
发布时间： - 摘要：A chlortoluron molecularly imprinted sensor was prepared on the surface of platinum oxide electrode through chemical polymerization.Gate’s change in the quantity of “gate-controlled” was utilized for manipulation of catalytic performance，combining with the catalytic amplification effect of platinum oxide on hydrogen peroxide.The sensitivity of sensor was improved effectively and the detection method for chlortoluron residue in environment was developed.In addition，the catalytic effect of platinum oxide electrode to hydrogen peroxide and the polymerization ratio of molecular imprinted membrane were studied.The hydrogen peroxide concentration,elution time and the re-adsorption time were optimized.Under the optimal conditions，the concentration of chlortoluron was negatively correlated with intensity of the catalytic current of platinum oxide electrode in the range of 1.0×10-8-8.0×10-6 mol/L，and the detection limit was 5.4×10-9 mol/L.The sensor was successfully applied in the detection of farmland water with recoveries of 98.5%-102.0%.关键词：molecularly imprinted sensor;gate control;chlortoluron;catalysis
- 2669
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- 1188
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- 6
发布时间： - 摘要：A simple,sensitive and accurate method consisted of ultrasound assisted extraction （UAE） coupled with QuEChERS and high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS） was developed for the determination of quinocetone （QCT） in liver tissue of fish.The extraction solvent,extraction time and solid sorbent were optimized.The liver tissues were extracted with ethyl acetate,and purified by the mixture of primary secondary amine（PSA） and graphitized carbon blacks（GCB）.The identification of QCT were achieved by using electrospray ionization in positive ion mode （ESI+） under multiple reaction monitoring（MRM） mode.The analysis of QCT was performed by the external standard method.The calibration curve was linear in the range of 5-100 μg/L with a correlation coefficient of 0.998 8.The limit of detection（LOD,S/N=3） was 5 μg/kg and the limit of quantitation（LOQ,S/N=10） was 10 μg/kg.The method was applied in the determination of QCT in the hybrid snakehead liver tissues,and the recoveries at three spiked levels of 10,25,100 μg/kg ranged from 98.6% to 110.0% with relative standard deviations （RSDs,n=3） of 5.9%-10.1%.The proposed method was applied in the final residue detection after feeding Hybrid Snakehead with feed containing 75 mg/kg QCT for 60 consecutive days.The result showed that QCT was depleted quite fast in hybrid snakehead,and the elimination half life time of snakehead was 2.31 h.Therefore,it could be concluded that QCT was safe in feeding Hybrid Snakehead.关键词：ultrasound-assisted extraction（UAE）;QuEChERS;HPLC-MS/MS;liver tissue;quinocetone（QCT）
- 2154
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- 1030
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- 3
发布时间： - 摘要：An on-line gel permeation chromatography combined with gas chromatography-mass spectrometric(GPC/GC-MS) method was developed for the determination of eighteen organochlorine pesticides in atmospheric dust.The sample was simplified by QuEChERS method,extracted with acetonitrile and cleaned with graphitized carbon black(GCB)，then filtrated by one step of centrifugation before detection.By this method,8-10 samples can be treated within 30 min，and after coupled with GPC purification，the analysis time could be shortened，and the working efficiency and the accuracy of results could be improved.The result indicated that the calibration curves were liner in the range of 0.025-2.0 mg/L， with correlation coefficients of 0.991 9-0.999 6.The limits of detection for the sample were in the range of 3.2-14.6 μg/kg and the limits of quantitation were 10.7-48.7 μg/kg.The mean recoveries of eighteen organochlorine pesticides at spiked levels of 0.2，1.0 mg/kg were in the range of 78.6%-117.3%，with relative standard deviations(RSDs，n=5) of 1.3%-5.1%.关键词：pesticide residues;GPC/GC-MS;QuEChERS method
- 3079
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- 1012
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- 4
发布时间： - 摘要：To improve the precision and robustness of the model for the chlorpyrifos active ingredient in pesticide EC by near infrared spectroscopy,synergy interval PLS(siPLS) combined with genetic algorithm(GA) was implemented to optimize the feature variables,and cross-validation method was used to select the optimal PLS factors and the variables.The results showed that the optimal model was achieved with R2p of 0.972,root mean square error of prediction(RMSEP) of 0.353% in the prediction set when 81 variables and 11 PLS factors were included.Experimental results showed that siPLS combined with GA could eliminate a large margin of the redundant information and irrelevant information in pesticide EC spectroscopy,and reduce the complexity of the developed model.The precision and robustness of the model were also improved.关键词：near infrared(NIR) spectroscopy;synergy interval PLS(siPLS);genetic algorithm(GA);pesticide formulation;chlorpyrifos
- 2082
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- 1126
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- 6
发布时间： - 摘要：A capillary electrophoresis(CE) method for the determination of alendronate was developed by using 4-methoxybenzenesulfonyl chlorine(MOBS-Cl) as a pre-column derivatization reagent.The derivative reaction conditions were investigated,and the optimal derivative conditions were as follows:the alendronate reacted with MOBS-Cl in 20 mmol/L borate buffer solution(pH 11.5),and the molar ratio of alendronate to MOBS-Cl was 1∶10.The temperature for the derivatization reaction was 50 ℃ and the reaction time was 10 min.The separation of the derivatives was achieved on capillary column by using 20 mmol/L borate buffer solution(pH 9.3) at a temperature of 25 ℃ and a separation voltage of 20 kV.The injection was carried out under the pressure of 0.5 psi for 5 s,and the detecting wavelength of diode array(DAD) was 233 nm.The calibration curves were linear in the range of 1.0-400 μg/mL,and the limits of detection were 0.5-1.0 μg/mL.This proposed method was applied in the determination of alendronate in pharmaceutical preparations and urine samples with satisfactory results.关键词：capillary electrophoresis;4-methoxybenzenesulfonyl chlorine;alendronate;pre column derivatization
- 1826
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- 1177
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- 0
发布时间： - 摘要：A new sample purification method was developed for the determination of low levels of DDTs in soils.The tested soil was extracted with a mixture of hexane-acetone(1∶1) by ultrasonic method.The soil extracts was purified with a patented four-channel purification chromatograph before analysis by gas chromatography with electron capture detector(GC/ECD).Effects of different column packs and elution solvents on recoveries of DDTs were investigated.The results showed that by using ultrasonic extraction，new mixed filling material for the chromatogram column and elution with dichloromethane-n-hexane(4∶1)，the recoveries of DDTs were between 83.5% and 90.3%，and the method detection limits were between 2.0 ng?g-1 and 5.4 ng?g-1，implying that the method can be used for the determination of low levels of DDTs in soils.In addition，the spiked recoveries of DDTs based on the ultrasonic extraction and Soxhlet extraction were compared under the optimal purification conditions.The results showed that the recovery of the Soxhlet extraction method is higher than that of the ultrasonic extraction method，but the the former need consume more time.关键词：four-channel purification chromatography;sample pre-treatment;soil;DDTs;GC/ECD
- 1974
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- 963
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- 5
发布时间： - 摘要：The metallothionein-like(MT-like) was separated and purified by using a high-pressure gel column,then a new hyphenated technique of high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry(HPLC-ICP-MS) was established based on the protein ultraviolet absorption and the metal element combined,and with Tris-acetate buffer solution(20 mmol/L,pH 7.5) as mobile phase at a flow rate of 0.5 mL/min.The separation effect and reproducibility of bovine serum protein from Rabbit Liver Zn-Metallothionein(Zn-MTs) fraction were studied,and the linear relationship,detection limit and correlation of UV and ICP-MS were also investigated.The experimental results indicated that it had a good reproducibility on Zn-MTs group separation with RSD(n=6) less than 5%,and Zn signal had a good quantity relationship with UV absorption in Zn-MTs with a linear correlation coefficient of 0.999 5.The detection limit of Zn-MTs protein was relatively low that was based on Zn detected by ICP-MS.关键词：high performance liquid chromatography-inductively coupled plasma mass spectrometry;metallothionein-like;heavy metals induction
- 1937
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- 881
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- 1
发布时间： - 摘要：A method was established for the simultaneous determination of para red，sudan Ⅰ，sudanⅡ，sudan Ⅲ，and sudan Ⅳ residues in eggs by dispersive solid phase extraction(dSPE) combined with high performance liquid chromatography(HPLC).The samples were extracted with n-hexane by ultrasonic technique，and then enriched and cleaned up with Diol silica gel absorbent.The separation of the target compounds were performed on a Phenomenex Luna C18 column(50 mm×2.0 mm，5 μm) by using acetonitrile-water as mobile phase by gradient elution.The detection of the target compounds was performed with an ultraviolet-visible(UV-vis) detector at 500 nm and quantified by the external standard method.The results showed that the linear ranges of para red and four sudan dyes were between 0.1 mg?L-1and 10.0 mg?L-1 with correlation coefficients more than 0.999.The average recoveries at three spiked levels ranged from 81.2% to 94.2% with relative standard deviations(RSDs) of 3.4%-5.3%.The limits of detection(LODs) were in the range of 0.018-0.030 mg?kg-1，and the limits of quantitation(LOQs) were 0.06-0.10 mg?kg-1.The developed method is simple，rapid and sensitive,and is suitable for the determination of trace dyes residues in eggs.关键词：dispersive solid phase extraction(dSPE);Para red;sudan dyes;egg;high performance liquid chromatography(HPLC)
- 2002
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- 1167
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- 8
发布时间： - 摘要：An ultrasound-assisted ion chromatographic method was developed for the determinination of hexavalent chromium in the chromium contaminated sites.Using 0.3 mol/L KCl solution as extractant,12 soil samples were treated by ultrasonic assisted extraction for 20 min.The sample was analyzed on a Metrosep A Supp 4-250（250 mm×4.0 mm） anion separation column,using a mixture of 4 mmol/L Na2CO3-1 mmol/L NaHCO3 as eluent.The method showed a good linearity（r2=0.999 8） in the range of 0.01-20 mg/L for the hexavalent chromium.The detection limit was 0.003 mg/L,the spiked recoveries were in the range of 96.4%-106.8% with RSDs（n=3） of 0.56%.The method was simple,rapid and accurate,and was suitable for the investigation on the chromium contaminated sites.关键词：ion chromatography;chromium pollution;hexavalent chromium;soil
- 2501
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- 1014
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- 19
发布时间： - 摘要：In the present study,a reference material of kepone in dichloromethane was developed.The qualitative analysis of the raw material of kepone was conducted by gas chromatography coupled with mass spectrometry（GC-MS）,as well as infrared spectroscopy（IR）,and its purity was characterized to be 99.9% by multi-lab certification with gas chromatography equipped with fire ionization detector（GC/FID）.In （20 ± 4） ℃,the solution of kepone in dichloromethane was prepared by weight capacity method,and then followed by the assessment of homogeneity,stability,quantity value.The uncertainties caused in the whole producing processes of the reference material were analyzed and evaluated.关键词：kepone;reference material;characterization;uncertainty evaluation
- 2131
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- 974
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- 0
发布时间： - 摘要：Biogenic monoamine is known as an important series of neurotransmitters.They are involved in a variety of biological activities，such as mental activity，stress and emotion controlling，learning，physical movement，etc.The determination of monoamine neurotransmitters and their metabolites is significant for the diagnosis and control of many diseases，drug development and the neurological fundamental research.However，trace-level of basal monoamine and complex matrix of biological sample make their efficient separation and accuracy quantification extremely difficult.In this paper，the methods for the sample preparation of monoamine neurotransmitters in biological sample were reviewed，and the new progress in analysis of monoamine neurotransmitters was introduced.The future trends of monoamine neurotransmitters analysis was also prospected.关键词：monoamine neurotransmitters;sample preparation;analysis;review
- 2084
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- 1224
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- 3
发布时间： - 摘要：As one of the most important researches of electrochemical sensors，molecular imprinted sensors have obtained great achievements over the past 10 years.Several procedures are used to prepare molecularly imprinted polymer(MIP) films on transducer surfaces，including drop-coating or spin-coating of a solution on a pre-prepared polymer，in situ chemical polymerization and electropolymerization.In comparison with other procedures of MIP film preparation，the MIP films prepared by electropolymerization have superior properties with respect to adherence to the transducer surface，simplicity and speed of preparation，easy control of the film thickness and high reproducibility.This review describes a class of polymers prepared by electropolymerization that employs the concept of molecular imprinting for chemical sensing.The choice of functional monomers and the removal of templates in the electrosynthesized preparation of MIP films are discussed.An evaluation of literatures on these molecularly imprinted polymers(MIPs) applied as recognition elements of several types of chemical sensors is described.The possibilities for routine work in the near future are presented.关键词：molecular imprinted polymer;electropolymerization;sensor;review
- 2887
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- 1339
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- 7
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