最新刊期
卷 31 ， 期 3 ， 2012
- 摘要：The relationships between molecular structures of dietary flavonoids and their affinities for bovine serum albumin（BSA） were investigated by fluorescence titration analysis.The results indicated that the binding process with BSA was significantly affected by the molecular structures of flavonoids.The methylation of hydroxyl groups in flavonoids could enhance their binding affinities for BSA by 1 to 794 times.Hydroxylation on rings of A,B and C also strongly influenced the affinities for BSA.The glycosylation weakened the affinities for BSA by 1-2 orders of magnitude depending on the conjugation site and the class of sugar moiety.The hydrogenation of the C2‖C3 double bond slightly decreased the binding affinities.The galloylated catechins and pyrogallol type catechins exhibited higher binding affinities for BSA than the non-galloylated catechins and catechol-type catechins,respectively.The affinities for BSA increased with the increase of partition coefficients and decreased with the increase of hydrogen bond donor and acceptor numbers of flavonoids,which suggested that the binding interaction was mainly caused by hydrophobic forces.关键词：structure-affinity;flavonoids;BSA;protein binding;fluorescence titration
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发布时间： - 摘要：The toxicity of dauricine on daudi cell of B cell lymphoma was investigated by atomic force microscopy,CCK-8 assay and flow cytometer method.The results showed that dauricine could suppress the proliferation of daudi cells.By CCK-8 assay,it was found that cell viability was related with the reaction time and drug concentration.When 10-50 μmol/L dauricine was incubated with daudi cells for 24 h and 48 h,respectively,the cell viability declined from (89.8±4.3)% to (11.2±3.2)% and (68.9±2.6)% to (2.5±0.5)%,respectively.In addition,daudi cells were cultured with different concentrations of dauricine for 24 h,the result revealed that the apoptosis rate increased from 5.2% to 28.2% (60 μmol/L).AFM data showed that control cells were round and the surface was smooth.After treated with dauricine,daudi cell collapsed, the ultrastructure revealed that cell surface was rough and full of bumps and holes.Furthermore,daudi cells were treated with different concentrations of dauricine,the mitochondrial membrane potential of cell decreased with the increase of the dauricine concentration.Dauricine significantly inhibited the growth and proliferation of daudi cells.关键词：dauricine;atomic force microscope;cell toxicity;ultrasructure;daudi cell;cell apoptosis
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发布时间： - 摘要：Neutral fraction of cigarette particulate matter was investigated by comprehensive two-dimensional gas chromatography coupled with time of flight mass spectrometric(GC×GC-TOF MS) method.An HP-5MS(50 m×0.2 mm i.d.×0.33 μm) column was chosen as the first dimensional column and a DB-17MS(1.7 m×0.1 mm i.d.×0.1 μm) as the second dimensional column to separate and analyze the neutral constituents of smoke particulate matter of high-quality tobacco.Total of 1 464 compounds were tentatively identified by TOF MS software based on auto data processing combined with manual data processing.The structured related compounds such as ketones and aldehydes eluted in bands or clusters in the GC×GC chromatograph were investigated.The retention time for 36 flavor constituents in the first dimension and second dimension were discussed,and the characteristics of the aldehydes in the comprehensive two-dimensional gas chromatography were studied. The information and the interpretations of spectra characteristics will enhance the reliability of compound identification and be helpful in the study of tobacco smoke and other complex system.关键词：comprehensive two-dimensional gas chromatography(GC×GC);time of flight mass spectrometry(TOF MS);neutral constituents;cigarette particulate matter;spectra characteristics
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发布时间： - 摘要：A simultaneous determination method was developed for the reliable screening,quantification and confirmation of 24 allergens in cosmetics by gas chromatography-mass spectrometry（GC-MS）.The 24 allergens were extracted from cosmetics with methanol,then determined by GC-MS with the external standard method under the selected ion mode（SIM）.The calibration curves showed good linearities in the range of 0.2-100 mg/L with correlative coefficients (r2) larger than 0.995.The detection limits were in the range of 2-10 mg/kg,and the average recoveries were 80%-104% with relative standard deviations of 1.8%-9.3%.The method was rapid,accurate and sensitive.The positive detection rate of 24 allergens in 150 samples of 77 patients using cosmetics was 78%,and there was at least one allergen measured value above 10 mg/kg in 81.2% of the positive samples.24 allergens in the cosmetics used by 71 patients were detected out and the detection rate was 92.2%,which at least one allergen measured value above 10 mg/kg was 90.1%.24 allergens are the major allergens in cosmetic contact dermatitis.关键词：gas chromatography-mass spectrometry;cosmetics;allergen;contact dermatitis
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发布时间： - 摘要：The electrochemical behavior of interaction between salvianolic acid B (SalB) and bovine serum album in(BSA) was investigated by cyclic voltammetry and square wave voltammetry based on DNA-modified glass carbon electrode (GCE) in 0.01 mol/L phosphate buffer solution (pH 7.4).SalB generated a sensitive oxidation peak of 0-100 V at the DNA modified GCE.After addition of BSA into the SalB solution,the oxidation current decreased and the peak potential shifted positively.The electrochemical parameters,such as the charge-transfer coefficient α and the standard electron-transfer rate constant ks were also changed.The binding number m of 1.71 and the binding constant β of 1.00×108 L/mol were calculated according to the data of the oxidation current,which indicated that SalB could combine with BSA to generate a non-electric complexes with combination ratio of 2∶1.The results were in agreement with that provided by the fluorescence spectrometric method.关键词：salvianolic acid B(SalB);bovine serum albumin(BSA);DNA modified electrode;electrochemical method
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发布时间： - 摘要：A gold nanoparticles/multi-walled carbon nanotubes modified glassy carbon electrode（AuNPs-CNTs/GCE） was prepared,and the electrochemical behavior of 4-n-octylphenol（NP） on the modified electrode was investigated by cyclic voltammetry（CV） and linear sweep voltammetric（LSV） method.In BR buffer solution,a sensitive oxidation peak of NP was found at+0.51 V and the oxidation peak current was significantly enhanced by AuNPs-CNTs/GCE compared with those by bare glassy carbon electrode（GCE） and multi-walled carbon nanotubes modified glassy carbon electrode（CNTs/GCE）.Based on this,a simple and sensitive electroanalytical method was developed for the determination of NP.Factors such as pH,scan rate and accumulation time that influenced the detection processes were optimized.Under the optimal conditions,the oxidation peak current was proportional to NP concentration in wide linear ranges of 0.05-4 μmol/L and 6-14 μmol/L with correlation coefficients of 0.998 4 and 0.993 3,respectively.The low detection limit was 0.023 μmol/L.The spiked recoveries of the samples were in the range of 95%-104%.With the advantages of simple preparation,high sensitivity,low cost,excellent reproducibility and stability,the proposed method could be used in the determination of NP in environmental sample.关键词：multi-walled carbon nanotubes;4-n-nonylphenol（NP）;gold nanoparticles;voltammery
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发布时间： - 摘要：A high performance liquid chromatography-tandem mass spectrometric（HPLC-MS/MS）method was developed for the determination of nine PAEs,including bis（2-methoxyethyl） phthalate（DMEP）,diethyl phthalate（DEP）,benzyl butyl phthalate（BBP）,bis（2-n-butoxyethyl） phthalate（DBEP）,dipentyl phthalate（DPP）,bis-4-methyl-2-pentyl） phthalate（BMPP）,dihexyl phthalate（DHXP）,bis（2-ethyl-h exyl） phthalate（DEHP）and di-n-octyl phthalate（DNOP） residues in tilapia sample.The samples were extracted with ethyl acetate,and purified with LC-Si solid phase extraction column.Methanol and formic acid-ammonium acetate buffer were used as mobile phase by gradient elution.The analysis of target compounds was carried out by HPLC-MS/MS with positive electrospray ionization（ESI+） under multiple reaction monitoring（MRM） mode.A matrix matched external standard was used for the quantitative analysis.The calibration curves for nine PAEs were in good linearities between their peak areas and concentrations of 1.0-200.0 μg?L-1 with correlation coefficients not less than 0.991 8.The average spiked recoveries ranged from 75% to 107%.The relative standard deviations of intra-batch and inter-batch were in the ranges of 1.9%-11.8% and 3.6%-13.1%,respectively.The proposed method was simple,rapid,sensitive and accutate,and could meet the requirements for residue analysis.关键词：high performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS）;tilapia;PAEs;solid phase extraction;residues
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发布时间： - 摘要：A sweeping-micellar electrokinetic chromatographic（sweeping-MEKC） method was used for the simultaneous separation and determination of chlorphenamine maleate，caffeine and acetaminophen in compound paracetamol and amantadine hydrochloride capsules.Effects of sodium dodecyl sulfate（SDS） concentration,separation voltage,injection time of sample,composition and concentration of background buffer on separation efficiency were optimized.An optimal separation of three compounds was obtained on an uncoated fused silica capillary column（50 cm×50 μm,effective length 35 cm） by using background buffer containing 80 mmol/L SDS,20 mmol/L NaH2PO4 and 15% acetonitrile at pH 2.2 with a constant temperature of 25 ℃.The detection wavelength was set at 210 nm,the separation voltage at-20 kV and the sample injection time for 60 s.The result indicated that the separation of three compounds was performed within 25 min with relative standard deviation（RSDs） of their peak areas less than 4%.The calibration curves showed good linearities in the ranges of 2.45-39.17 mg/L for chlorphenamine,1.61-25.76 mg/L for caffeine and 1.58-25.28 mg/L for acetaminophen,with detection limits（S/N=3） of 139,34,24 μg/L,respectively.The spiked recoveries for acetaminophen,caffeine and chlorphenamine maleate were 96%-101%,98%-102% and 96%-102%,respectively.关键词：sweeping;MEKC;chlorphenamine maleate;caffeine;acetaminophen
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发布时间： - 摘要：Three extraction solvents such as ammonium acetate solution（used in No.1025-18-2008 Bulletin of the Ministry of Agriculture）,acetonitrile and acetonitrile-10% sodium carbonate solution were used to extract nine β-agonists residues in pig liver,respectively,and the extraction efficiencies of targeted compounds were compared.The experimental results revealed that the recovery of penbutolol increased to 79% and that for fenoterol was 32% when using acetonitrile as extraction solvent.The recoveries of the eight drugs（ractopamine,clenbuterol,salbutamol,terbutaline,cimaterol,clorprenaline,tulobuterol and penbutolol） were more than 80% except that 72% of recovery for fenoterol when using acetonitrile-10% sodium carbonate as extraction solvent.A liquid chromatography-tandem mass spectrometric method was established for the simultaneous determination of nine β-agonists residues in pig liver.Under the optimal conditions,the linear ranges of nine analytes were between 0.50 μg/kg and 25 μg/kg with correlation coefficients（r） more than 0.99.At the spiked levels of 0.50,2.0,10 μg/kg,the mean recoveries of nine β-agonists in pig liver ranged from 71% to 105%,with intra- and inter-RSD less than 15%.All the detection limits of nine β-agonists were 0.2 μg/kg.The method could meet the requirements for residue analysis on accuracy and precision.关键词：β-agonist;pretreatment;pig liver;high performance liquid chromatography-tandem mass spectrometry;comparison
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发布时间： - 摘要：A methodology regarding the preparation and certification of certified reference material (CRM) of allure red solution was presented.After the qualitative analysis on pure substance of allure red by liquid chromatography-mass spectrometry(LC-LTQ/MS) and 1H NMR spectrum,the purity of allure red was certified by high performance liquid chromatography(HPLC),the purity certification of allure red was performed at 240 nm with methanol and 0.1 mol/L ammonium acetate solution as mobile phase,and the Intersil ODS-C18 column(250 mm×4.6 mm,5 μm) was used for analysis.The certification purity of allure red was 99.61%.To verify the result，six certification labs were performed,at the same time,the water content and volatile impurity were determined by the total gravimetric analysis(TGA)．Allure red solution CRM was prepared by the gravity-volume method．After the tests of homogeneity and stability，the concentration of allure red solution CRM was certified and the uncertainty was evaluated．The certified result was 100 mg/L and the expanded relative uncertainty was 1.0%(k=2).The allure red solution CRM was approved as a national CRM and could be applied in food safety detection.关键词：allure red;solution certified reference material;high performance liquid chromatography;uncertainty evaluation
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发布时间： - 摘要：The extraction effects of fluoroquinolones(FQs) and tetracyclines (TCs) in manure were compared experimantally by using different extractions,and the method of mixed extractions of EDTA-McIlvaine and 50%Mg(NO3)2-2.5% NH3?H2O was developed.The proportion of two extractions was explored.The result indicated that when the volume ratio of EDTA-McIlvaine and 50% Mg(NO3)2-2.5% NH3?H2O was 3∶1,the extraction ratios for the six antibiotics,including tetracycline(TC),chlortetracy(CTC),enrofloxacin(ENR),pefloxacin(PEF),danofloxain(DAR) and sarafloxacin(SAR) were between 84% and 92%.Based on this,the methods of solid phase extraction and purification for the six residued drugs were optimized through the investigation on different elution-volume and extraction columns.At the same time,the concentration method was established by optimizing the conditions that using nitrogen concentration and rotation-evaporation.Eventually,the simultaneous extraction and determination of fluoroquinolones(FQs) and tetracyclines(TCs) in manure by high performance capillary electrophoresis(HPCE) was established.Under the optimal chromatographic conditions,the linear ranges were between 3.125 mg/L and 100 mg/L,the limit of quantitation for six antibiotics were less than 0.1 mg/kg.At the spiked concentrations of 10.0,20.0,40.0 mg/L，recoveries of six antibiotics in manure ranged from 54% to 93% with relative standard deviations(RSDs) of 6.3%-8.9%.This method was quite simple,rapid and low-cost,and was successfully used in the detection of six antibiotics in manure around the city of Hefei.关键词：manure;pretreatment;fluoroquinolones;tetracyclines;high performance capillary electrophoresis(HPCE);simultaneous extraction
- 2099
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发布时间： - 摘要：The separation of 2′-AMP，3′-AMP and 5′-AMP were investigated by a nonaqueous capillary electrophoresis（NACE) method.Effects of pH* value，nonaqueous solvent，different category buffer on the separation efficiency were studied.The optimum separation conditions are as follows:running medium:200 mmol?L-1 Tris-H3BO3 containing 50% acetonitrile，pH* value:10.0; applied electric field:25 kV; column temperature:25 ℃; detection wavelength:260 nm，and samples were injected from the cathodal end of the capillary by 50 mbar for 5 s.Under the optimal conditions，there are excellent linearities between peak heights and concentrations of the analytes in the concentration range of 1-100 mg/L.The spiked recoveries ranged from 88% to 106% with RSDs less than 4%.The method was applied in the determination of adenosine samples with satisfactory results.关键词：nonaqueous capillary electrophoresis(NACE);single phosporic acidic adenosine;nucleoside;separation
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- 1000
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发布时间： - 摘要：Using meso-terakis(4-methoxyl-3-sulfonatophenyl) porphyrin(T(4-Mop)PS4) as an electrochemical probe,a new electroanalytical method for the determination of bovine serum albumin (BSA) was established based on the interaction of BSA with T(4-Mop)PS4.A good linear relationship was obtained between the variation of peak current and concentration of BSA in the range of 2.0×10-6-1.0×10-5 mol?L-1.The limit of detection(LOD) was 1.2×10-6 mol?L-1 and the relative standard deviation(RSD,n=8) for 50×10-6 mol?L-1 BSA was 20%.The supramolecular complex of T(4-Mop)PS4 with BSA was studied by three different methods,including spectrophotometry,fluorometry and linear sweep voltammetric(LSV) methods.The binding ratio and binding constant of T(4-Mop)PS4 with BSA were obtained.The experimental data demonstrated that T(4-Mop)PS4 could form a 1∶1 stable supramolecular complex with BSA,and hydrophobic interaction is the main reaction between them.关键词：Meso-terakis(4-methoxyl-3-sulfonatophenyl)porphyrin(T(4-Mop)PS4);bovine-serum albumin(BSA);polargraphy;binding constant;binding ratio;interaction
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发布时间： - 摘要：A method based on solid-phase microextraction（SPME） technique followed by gas chromatography with mass spectrometry detector（GC-MS） was developed for the determination of 8 phthalic acid esters（PAEs） in liquid cosmetics.The parameters affecting the partitions of analytes such as fiber coating,extraction temperature,stirring speed and salt concentration were optimized.The final SPME method employed a 65 μm polydimethylsiloxane（PDMS）/divinylbenzene（DVB） coating fiber and the saturated sodium chloride solution at 90 ℃ under stir for 60 min，then the fiber was introduced into the GC injector port and the extract was desorbed at 250 ℃ for 4 min.The detection limits for the other 7 PAEs except for DPhP ranged from 0.7 μg?kg-1 to 13.6 μg?kg-1，and the recoveries for spiked samples were between 83% and 97% with RSDs（n=5）of 2.5%-10.0% .For its weak adsorption to fiber coating，the detection limit for DPhP was 75 μg?kg-1 ，and the recovery was 70% with RSD（n=5） of 13.9%．The method was applied in the determination of 8 PAEs in liquid samples with satisfactory results.关键词：solid-phase microextraction;gas chromatography-mass spectrometry;liquid cosmetics;phthalic acid esters;plasticizer
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发布时间： - 摘要：The fluorescence spectral characteristic of berberine hydrochloride（BER） was studied in the cucurbit（n=8）uril（Q［8］） aqueous medium.In this medium,Q［8］ and BER formed a supramolecular compound which resulted in the increase of BER fluorescence intensity.A good linear relationship between fluorescence intensity of the system and BER concentration was obtained.Based on this,a novel fluorimetric method was developed for the determination of BER concentration in the cucurbit（n=8）uril medium.Under the optimum conditions,the calibration curve was linear over BER concentration range of 1.90×10-8-1.00×10-5 mol?L-1,with a correlation coefficient（r） of 0.996 1 and a detection limit of 1.90×10-8 mol?L-1.The proposed method was simple,accurate,and could avoid using the toxic solvents and tedious solvent-extraction.And the method was applied in the determination of BER in tablets,serum and urine sample,and the result was in good consistence with those obtained by the pharmacopoeia method.关键词：cucurbit（n=8） uril;berberine hydrochloride;fluorescence
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发布时间： - 摘要：The relationships of solid waste autoclaved samples compressive strength and their crystallinity degrees，hydrate amounts were studied with dissolved amount difference and bound water amount measured with loss on ignition and acid digestion method.The results showed that the crystallinity degrees of autoclaved samples，such as fly ash，waste glass and waste concrete are in a low level except that the crystallinity degree of autoclaved steel slag sample is higher.The dissolved amount difference，bound water amount and crystallinity degree of the autoclaved samples were related to their hydrate types.The crystallinity degrees of autoclaved samples could be indirectly represented as the ratios of well-crystallized hydrate amounts to total hydrate amounts in the autoclaved samples，and used to determine the autoclaved schedule and guide the technology optimization for autoclaved products.There is a reasonable crystallinity degree range for the compressive strength of autoclaved samples.关键词：solid waste;autoclaved silicate products;bound water amount;dissolved amount difference;crystallinity degree;hydrate product
- 2005
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发布时间： - 摘要：CdTe quantum dots(QDs) modified with —COOH on its′surface were synthesized by using mercaptoacetic acid hydrothermal synthesis，and QDs were connected to the Fe3O4 nanoparticles to prepare CdTe/Fe3O4 magnetic quantum dots.The magnetic quantum dots could be modified on the graphite electrode surface by magnetic force.In pH 7.5 PBS buffer solution，ECL of CdTe quantum dots can be generated by promotion of H2O2.There was a good linear relationship between ECL intensity and H2O2 concentration in the range of 4-100 μmol/L with a detection limit of 0.24 μmol/L.Based on this，an ECL method for the determination of hydrogen peroxide was established.The method was successfully applied in the determination of hydrogen peroxide concentration in Leersia hexandra Swartz extracting juice.With the aid of nano-Fe3O4 magnetic particles，the sensor could easily form and renewal the sensitive membrane by magnetic controlling.The experimental operation was simplified and the ECL intensity was improved significantly.关键词：magnetic quantum dots;modified electrode;hydrogen peroxide;electrochemiluminescence
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发布时间： - 摘要：A new kind of modified amorphous silica materials HTS-n（s） containing both acidic and basic centers was synthesized.Both large BET surface area and 3-4 nm micropores of the composites were obtained after they were soaked with alkaline solution.This new material can selectively adsorb and remove the industry dyes infectants such as malachite green（MG） and crystal violet（CV） in culture water.After the centrifugation to separate the solution and the solid,the amounts of residual dye in solution were analyzed by liquid chromatography-tandem mass spectrometry（LC-MS/MS）.These modified silicas exhibited a much better adsorption capacity for industry dyes such as MG and CV than that of active carbon and zeolite NaY.关键词：modified amorphous silica;hydrotalcite;malachite green;crystal violet
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发布时间： - 摘要：After some pretreatments to the original spectra and using the frontal N coefficients of the fast Fourier transform(FFT) as the input variables of the artificial neural network(ANN)，a lot of useful information was assured to participate in modeling，and the advanced filter function of the FFT was also realized.After modeling the octane in gasoline and the calorific value in coal powder，the FFT-RBF(the radial basis function network) model was found to be good，for example，when using the frontal 20 coefficients of FFT，the root mean square error(RMSEP) of prediction of the octane is 0.152，and its correlation coefficient is 0.976，and when using the frontal 30 coefficients of FFT，the RMSEP of the Qgr-d of the coal powder is 0.256，and its correlation coefficient is 0.923 .The research illustrated that the ANN NIR quantitative analysis method based on the FFT，especially the FFT-RBF had the tremendous advantage in NIR prediction function.关键词：NIR;FT;ANN;quantitative analysis
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- 2
发布时间： -
Determination of N-Acyl-homoserine Lactones Signal Molecules by Gas Chromatography-Mass Spectrometry
摘要：Determination of N-Acyl-homoserine Lactones Signal Molecules by Gas Chromatography-Mass Spectrometry关键词：N-acyl-homoserine lactones;gas chromatography-mass spectrometry(GC-MS);quorum sensing signal molecule;bacteria- 2338
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发布时间： - 摘要：A new ultrasonic-assisted extraction followed by dispersive liquid-liquid micro-extraction（DLLME） and GC-MS analysis method was developed for the simultaneous determination of eight alkenylbenzenes and other flavor-related compounds including safrole,coumarin,6-methylcoumarin,7-metheoxycoumarin,estragole,methyleugenol,pulegone and thujone in tobacco additives.The different parameters affecting the whole process such as the type and volume of extraction and disperser solvents,the salt addition and the extraction time were studied.Under the optimum conditions,the enrichment factors（EF） ranged from 140 to 208.The linear relationships of eight alkenylbenzenes and other flavor-related compounds were obtained in the range of 0.4-928 μg/L,with correlation coefficients（r2） over 0.998 9.The limits of detection（LOD） and the limits of quantitation（LOQ） were in the ranges of 0.04-0.24 μg/L and 0.13-0.80 μg/L,respectively.The average recoveries were in the range of 90%-100% with relative standard deviations（RSDs） of 2.4%-6.7%.The method was successfully applied in the analysis of real tobacco flavor additive samples.Compared with the industry recommended standard method,lower concentrations of detection were achieved due to the high enrichment power of DLLME.Therefore,this method shows tremendous potential in trace analysis of alkenylbenzenes and other flavor-related compounds in real samples.关键词：alkenylbenzenes;dispersive liquid-liquid microextraction;GC-MS;tobacco additives
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发布时间： - 摘要：A high-performance liquid chromatography-mass spectrometric method was developed for the determination of L-carnitine in infant formula milk powder.After pretreatment procedure，the sample was separated on a C4 （4.6 mm×250 mm，5 μm） column using methanol-water （10∶90） as mobile phase with a flow rate of 1.0 mL?min-1，a column temperature of 25 ℃ and injection volume of 10 μL.The split ratio of post column was 1∶3.The target compound was detected under multiple reaction monitoring（MRM） mode with positive ion using m/z 162.2→103.1 as the quantitation ions.Each analysis was completed within 10 min.A good linear calibration for L-carnitine was obtained in the range of 0.40-10.0 mg?L-1 with a correlation coefficient of 0.999 3.The spiked recoveries were in the range of 87%-106%.The limit of detection（S/N=3） and limit of quantitation（S/N=10） of L-carnitine were 39.0 ng and 116.9 ng，respectively.The proposed method was simple，sensitive and reproducible，and was suitable for the determination of L-carnitine in infant formula food.关键词：L-carnitine;HPLC-MS;infant formula milk powder
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- 1995
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- 11
发布时间： - 摘要：As the third generation of genetic marker，the analysis of single nucleotide polymorphisms （SNPs） has a great significance for the pathogeny and early medical diagnosis of gene diseases，and has become a hotspot of analytical chemistry and life science research.In recent years，the electrochemical biosensors have been widely used in SNPs assay due to its advantages of high-sensitivity，simple-design，low-cost，easy miniaturization and automation.In this paper，the principle of SNPs typing，electrochemical biosensor technology and signal amplification methods for SNPs are introduced.Moreover，the current research progress on electrochemical detection for SNPs is summarized，and the future direction of SNPs electrochemical detection is discussed.关键词：single nucleotide polymorphisms;biosensor;electrochemical detection;signal amplification;research progress
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