最新刊期
卷 31 ， 期 5 ， 2012
- 摘要：A high performance liquid chromatography-tandem mass spectrometric(HPLC-MS/MS) method was developed for the simultaneous determination of ractopamine and clenbuterol in processed meats.A new cation exchange chromatographic column was utilized to separate target compounds and an improved pre-treatment method was uesed in this study.The eluent solution types and chromatographic parameters were optimized. The optimal conditions were as follows: using a flow rate of 0.4 mL?min-1，a injection volume of 10 μL and a column temperature of 40 ℃.The homogenized samples were extracted with 0.02 mol?L-1 ammonium acetate(pH 5.2)，hydrolyzed with 30 μL β-glucuronidase/arylsulfatase，centrifuged，and cleaned through solid phase extraction column. The calibration curves showed good linearities for two target compounds in the range of 0.1-100 μg?L-1.The limits of detection and quantitation of two target compounds were not more than 0.04 μg/kg and 0.15 μg/kg，respectively.The spiked recoveries for the processed meats ranged from 72% to 98% with RSDs less than 8.5%.This proposed method was simple and sensitive,and was suitable for the quantification of ractopamine and clenbuterol in processed meats.关键词：high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS);processed meat;processing method;ractopamine;clenbuterol
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发布时间： - 摘要：A silver-modified piezoelectric quartz crystal probe was involved in constructing piezoelectric biosensor for detection of hydrogen sulfide positive genus which releases hydrogen sulfide during metabolism. This biosensor was based on the special affinity of hydrogen sulfide on silver and the classic piezoelectric quartz crystal gas-mass response. The results indicated that this biosensor showed an excellent specificity to distinguish the hydrogen sulfide positive genus from the negative. The optimum concentration of cysteine in culture medium was obtained to be 0.05%. The biosensor avoided direct contact of the probe with culture medium，which could limited most influence in the liquid-mass response. This method would be expected to use in the automated detection of hydrogen sulfide positive genus during cultivation.关键词：hydrogen sulfide positive genus;piezoelectric;sensor
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发布时间： - 摘要：Volatile components of Cortex Magnoliae Officinalis leaves from Hunan were extracted by steam distillation and analyzed by gas chromatography-mass spectrometry combined with chemometrics methods，namely heuristic evolving latent projections and selective ion analysis.Temperature-programmed retention indices were used to improve the reliability of qualitative analysis.Total 54 compounds were identified，accounting for 84.95% of the total content of volatile ingredients of the studied sample.The major constituents are alpha-,beta- and gamma-eudesmol，which account for 13.10%,28.21% and 14.67%，respectively.In addition，there are seven compounds with relatively high contents，e.g.alpha-pinene（2.96%），linalool（1.71%），paeonol（1.88%），caryophyllene（2.04%），eremophilene（3.60%），alpha-selinene（3.84%） and 1,1,4,7-tetramethyl-1A,2,3,4,4A,5,6,7B-octahydro-1H-cyclopropa［E］azulene（1.34%）.The results indicated that employing chemometric methods in the analysis of the volatile chemical components in Chinese traditional medicines can greatly enhance the accuracy of qualitative analysis.The results obtained is helpful to the plant resources- exploitation and utilization of Cortex Magnoliae Officinalis.关键词：Cortex Magnoliae Officinalis leaves;essential oil;gas chromatography-mass spectrometry（GC-MS）;heuristic evolving latent projections;selective ion analysis
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发布时间： - 摘要：A reversed-phase ion-pair chromatographic method using direct conductivity detection was developed for the determination of hexafluorophosphate（PF-6） ionic liquid anion.Chromatographic separation was performed on a Diamonsil C18 reversed-phase column using ion-pair reagent-citric acid-acetonitrile as mobile phase.The effects of ion-pair reagent,volume fraction of acetonitrile,pH and column temperature on the retention factor and separation of PF-6 were investigated.The mechanism of retention in the separation was discussed.The optimized chromatographic conditions for the determination of PF-6 were using 0.05 mmol/L tetrabutylammonium hydroxide（TBAH）-0.038 mmol/L citric acid-35% acetonitrile（pH 5.5） as mobile phase,at a flow rate of 1.0 mL/min and a column temperature of 40 ℃.Under the optimal conditions,the retention time of PF-6 was less than 15 min and the baseline separation of PF-6 was achieved without any interference by other common anions（Cl-,NO-3,F-,Br-,SO2-4 and BF-4）.The detection limit（S/N=3） for PF-6 was 0.25 mg/L.The good linear relationship was obtained between chromatographic peak area and concentration of PF-6 in the range of 0.5-100.0 mg/L.The relative standard deviations （RSD,n=5） of chromatographic peak area and retention time were 0.17% and 0.15%,respectively.The proposed method was applied in the determination of PF-6 in ionic liquids of 1-butyl-3-methylimidazolium hexafluorophosphate and 1-propyl-2,3- dimethylimidazolium hexafluorophosphate.The spiked recoveries of PF-6 were 99% and 104%,respectively.The good linearity and repeatability of the method could meet the requirements for the quantitative analysis of PF-6 in ionic liquids.The method is simple,accurate,reliable and practical.关键词：Ion-pair chromatography;conductivity detection;ionic liquid;hexafluorophosphate
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发布时间： - 摘要：A method based on matrix solid-phase dispersion(MSPD) and high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) using isotope dilution technique was developed for the simultaneous determination of four β2-agonists，e.g.clenbuterol，ractopamine，salbutamol and terbutaline in sausage sample.The sausage samples were graphitized with C18 and eluted with methanol.After enzymolysis，the extracts was purified with solid phase extraction MCX cartridges.The separation of analytes was performed by HPLC，and the identification of target compounds was achieved under multiple-reaction monitoring mode with electrospray ionization in positive mode.Four β2-agonists were quantified by the internal standard method.The calibration curves showed good linearities for four β2-agonists in the range of 0.2-20.0 μg/L with correlation coefficients (r2) more than 0.990.The limits of detection were 0.10 μg/kg for salbutamol and clenbuterol,and 0.15 μg/kg for terbutaline and ractopamine.The spiked recoveries ranged from 80% to 109% with relative standard deviations less than 10%.The method showed the advantages of simplicity，sensitivity and less consumption of sample and organic solvents，and could meet the requirements for the determination of clenbuterol，ractopamine，salbutamol and terbutaline in sausage sample.关键词：sausage;matrix solid-phase dispersion;β2-agonists;high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)
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发布时间： - 摘要：Raman spectroscopy as a rapid，non-destructively testing technique has been widely used in many fields.In this study，49 spectra of gasoline samples were collected with portable Raman spectrometer.Adaptive iteratively reweighted penalized least squares was employed to remove the strong fluorescence background of the spectra.The partial least squares（PLS） calibration model was established in the optimal conditions to predict the content of MTBE.Correlation coefficient，fitting error of training set samples and correlation coefficient，prediction error of test set samples were used to evaluate the quality of the model.The best model showed the satisfactory predictions for the four values mentioned above：0.996 0，0.316 1 and 0.996 6，0.490 1.The results showed that the method was suitable for the fast and reliable determination of the MTBE in gasoline.关键词：Raman spectroscopy;MTBE;baseline correction;airPLS;chemometrics
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发布时间： - 摘要：In pH 4.2-4.8 Britton-Robinson（B-R) buffer solution，moxifloxacin（MXFX) and gatifloxacin（GTF) of fluoroquinolone antibiotics（FLQs) could react with Cu（Ⅱ) to form chelate cations，which further bind with tetrachlorotetraiodo-fluoresceindisodium salt（Tf ) to form FLQs∶Cu（Ⅱ)∶Tf （ 1∶1∶1) ion association complexes.The system reactions resulted in the great enhancement of resonance Rayleigh scattering（RRS) and new RRS spectra appeared.The reaction systems of two drugs had similar spectral characteristics，the maximum RRS wavelength situated at 373 nm，and one small scattering peak situated at 590 nm.The intensities of RRS at 373 nm are proportional to the concentrations of antibiotics drugs in the ranges of 0.031-7.8 mg/L for MXFX and 0.029-9.0 mg/L for GTF.Based on this，a new method was developed for the determination of FLQs in capsule and human urine samples.The reaction mechanism and the reasons for RRS enhancement of the system were also investigated.关键词：moxifloxacin;gatifloxacin;tetrachlorotetraiodo-fluoresceindisodium salt;Cu（Ⅱ);resonance Rayleigh scattering
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发布时间： - 摘要：A method was developed for the simultaneous determination of 72 veterinary residues in shrimps by QuEChERS and high performance liquid chromatography-tandem mass spectrometry.The sample was extracted with 5%acetic acid-acetonitrile,and the supernatant liquid was directly purified with C18,meanwhile,acetonitrile was used for the precipitation of protein.The extract was evaporated under nitrogen stream,and redissolved with 1 mL 0.1%formic acid-acetonitrile（4∶1）.Prior to the injection into LC-MS/MS,the sample was filtered through a 0.22 μm filter membrane.The HPLC separation was performed on ZORBAX SB-C18 column by gradient elution with acetonitrile and 0.1%formic acid as mobile phase.The analysis of target compounds was carried out with electrospray ionization（ESI） under multi reaction monitoring（MRM） mode.The external standard method was used for quantification. Under the optimal conditions,the correlation coefficients for 97.2%of the veterinaries were larger than 0.95 in the linear range of 0.1-1 840 μg/kg,the limits of quantitation ranged from 0.02 μg/kg to 33.58 μg/kg.The recoveries of 72 veterinary at three spiked levels were between 61%and 119%,except that for dibutylsuccinate,cefapirin,cefquinome,ceftiofur,lincomycin ane diazinon were between 38%and 58%,and their relative standard deviations were in the range of 1.6%-20%.The established method was used for the screening and determination of real samples（pteris shrimp,freshwater shrimp and sea shrimp） bought from supermarket.It was shown that no residue was detected in the sea shrimp and pteris shrimp samples,and 4.0 μg/kg of sulfadiazine as well as 2.2 μg/kg of sulfamethoxazole were found in freshwater shrimp sample,but the concentrations were all lower than the MRLs.关键词：QuEChERS;LC-MS/MS;multi-residues;veterinary drugs;shrimp;determination
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发布时间： - 摘要：A method for the determination of chlormequat and mepiquat residues in samples from seeding cultivation products was established by accelerated solvent extraction-solid-phase extraction coupled with ultra-performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）.The samples were extracted with ASE 200 system and cleaned up with weak cation exchange（CBA） column.The identifications of chlormequat and mepiquat were performed on a HILIC column packed with 5 μm particles under isocratic LC conditions by using 0.1% formic acid in 20 mmol/L ammonium acetate（A） and acetonitrile（B）（ VA∶VB=40∶60）.The quantification of analytes was achieved by using electrospray ionization under positive ion mode（ESI+） with multiple reaction monitoring（MRM）.The result indicated that the calibration curves were linear in the range of 0.2-10 μg/kg for both compounds.The average recoveries at spiked concentration levels of 2，5,10 μg/kg ranged from 77% to 111% with relative standard deviations of 5.6%-21.7%.The limits of detection were 0.02 μg/kg and the limits of quantitation were 0.1 μg/kg for both compounds.The established method was simple，rapid，sensitive and specific，and was suitable for the identification and quantification of chlormequat and mepiquat residues in seeding cultivation.关键词：seeding cultivation;solid-phase extraction;accelerated solvent extraction;chlormequat;mepiquat;ultra-performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）
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发布时间： - 摘要：Water soluble L cysteine modified ZnS∶Mn2+ quantum dots（QDs） were prepared in aqueous solution under the room temperature,and characterized by infrared spectrometry,ultraviolet-visible spectrometry,fluorescence spectrometry and X-ray diffraction spectrometry.Based on the fluorescence quenching of ZnS∶Mn2+ QDs caused by folic acid（FA） ,the prepared QDs were evaluated as a fluorescence probe for FA detection.Factors affecting the fluorescence detection on FA were studied.Under the optimal conditions,the quenched fluorescence intensity was linear with FA concentration in the range of 1.0×10-6-7.0×10-5 mol?L-1 with correlation coefficient of 0.994.The limit of detection for FA was 9.6×10-7 mol?L-1.The proposed method was applied in the determination of folic acid in folic acid tablet and urine samples with satisfactory results.The mechanism for detection of FA was also investigated.关键词：folic acid;Mn-doped ZnS quantum dots;fluorescence determination;L-cysteine
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发布时间： - 摘要：A novel and easy method was developed for the separation of 5 nucleosides by capillary electrophoresis in co-electroosmotic mode using a polymeric ionic liquid(PIL)，poly(1-vinyl-3-ethylimidazolium bromide) as background electrolyte modifier.The polymeric ionic liquid，as a cationic polymer，was electrostatically attached to the negatively charged surface of the fused-silica capillary，generating a reversed electroosmotic flow.Effects of polymeric ionic liquid concentration and pH on the electroosmotic flow were studied.Effects of several factors such as background electrolytes(BGES) concentration and pH value on separation were also investigated.Under the optimized conditions，good separation of 5 nucleosides was achieved with high column efficiency and excellent reproducibility in 3.1 min.Meanwhile，the method was compared with capillary electrophoresis background electrolyte system without or with ionic liquid(IL or PIL)as additive.The results showed that the separation time of 5 nucleosides was reduced sharply and the separation efficiency was improved after adding PIL.The highest column efficiency was up to 950 000 plates/m.RSDs(n=5) of the migration time for the analytes were all no more than 0.38%.The method is simple，efficient and excellently reproducible and has a good application prospect.关键词：capillary electrophoresis;polymeric ionic liquid;co-electroosmotic mode;nucleosides
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发布时间： - 摘要：A high-performance liquid chromatography（HPLC） method for the determination of glucosamine in glucosamine sulfate potassium chloride capsules was developed.The separation of analyte was performed on a Hedera NH2 column （250 mm ×4.6 mm,5 μm） with acetonitrile and phosphate buffer （65∶35） as mobile phase,at a flow rate of 1.0 mL/min.The variable wavelength detector（VWD） was set at 195 nm.In the above chromatographic conditions,the calibration curve was linear over glucosamine concentration in the range of 1.6-2.4 g/L.The limit of detection（LOD） of glucosamine was 7.81 mg/L. The RSD（n=6） for the accuracy was 0.53% and the average recovery was 100%with RSD of 1.1%.This method is simple,accurate and with no need of derivation,and is suitable for the determination of glucosamine.关键词：glucosamine sulfate potassium chloride capsules;glucosamine;high-performance liquid chromatography（HPLC）;determination
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发布时间： - 摘要：An on-line removing matrix method with pre-concentration of the analytes was developed for the simultaneous determination of impurity anions（e.g.chloride,sulfate） in ink dye by ion chromatography（IC）.The sample was diluted with de-ionized water,filtrated by 0.22 μm nylon membrane and then injected into the IC system directly without any further pretreatment.The sample solution in the loop was delivered by de-ionized water,and then filtrated on line by DIONEX OnGuard II P column and IonPac NG1 column for pre-removing of dyestuff and hydrophobic components.The analytes flowing out in the dead time were concentrated in the high capacity anion-exchange guard column IonPac AG11-HC.The concentrator then stepped in the IC system when the valve switched to injection mode.The chloride and sulfate were separated on a DIONEX IonPac AS23（4 mm×250 mm） column by using 4.5 mmol/L Na2CO3 -0.8 mmol/L NaHCO3 as the eluent at a flow rate of 1.2 mL/min.The analytes were detected with a Dionex DS6 conductive detector and quantitively analyzed by the external standard method.The results indicated that the linear ranges of Cl－and SO2-4 were 0.05-5.0 mg/L（r=0.999 8） and 0.1-10 mg/L（r=0.999 7）,respectively.The average recoveries were in the range of 94%-103% with relative standard deviations（RSDs） no more than 1.0%.The detection limits（S/N=3） were 0.02 mg/L for Cl- and 0.05 mg/L for SO2-4.The method was applied in the determination of chloride and sulfate in ink dye samples with satisfactory results.关键词：ion chromatography;ink dye;chloride;sulfate;on line removing matrix method
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发布时间： - 摘要：Electrocatalytic oxidation behaviors and electrochemical kinetics of methocarbamol （MET） were investigated at ［BnMIM］PF6 modified carbon paste electrode （［BnMIM］PF6/CPE）.The experimental results indicated that MET electrochemical behavior exhibits an irreversible electrochemical oxidation process at ［BnMIM］PF6/CPE.The electrochemical kinetic parameters were determined by cyclic voltammetry（CV） and chronoamperometry（CA） at ［BnMIM］PF6/CPE.The catalytic oxidation peak current of MET versus its concentration had a good linear relationship in the concentration range of 3.0×10-5-1.0×10-2 mol?L-1 with a detection limit（S/N=3）of 3.3 ×10-6 mol?L-1 by square wave voltammetry（SWV）.The proposed method was successfully applied in the determination of MET contents in commercial tablet samples，with their relative standard deviations of 1.5% -2.5% and recoveries of 98% -99%.关键词：methocarbamol;carbon paste electrode;ionic liquid;electrocatalytic oxidation
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发布时间： - 摘要：Using paracetamol（PCT） as template and methylacrylic acid as functional monomer, a molecular imprinted polymer film was synthesized on the surface of glassy carbon electrode（GCE） through in-situ polymerization by UV irradiation.After the template was removed with methanol and formic acid mixture solution, a paracetamol imprinted polymer film modified glassy carbon electrode（MIP-GCE） was prepared, and a method for the determination of PCT was developed with MIP-GCE.The sensor exhibited a good selectivity and sensitivity.The calibration curve was linear in the range of 5.0×10-5-1.0×10-3 mol?L-1 with a detection limit of 1.4×10-6 mol?L-1.The method was applied in the determination of PCT in drugs, with recoveries of 96%-105%.关键词：paracetamol;molecular imprinted film;glassy carbon electrode;electrochemistry;in-situ polymerization;UV irradiation
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发布时间： - 摘要：A high performance liquid chromatography-tandem mass spectrometryic（HPLC-MS/MS） method was established for the simultaneous determination of urea,biruet and dicyandiamide in foods.Samples were soaked and mixed in water,then removed proteins by adding acetonitrile and frozen centrifuged to remove fat.The clear liquid was evaporated to dryness,and the residue was dissolved in 1 mL 70% ACN solution,and filtrated with membrane.The analytes were identified by HPLC-MS/MS with the positive electrospray ionization（ESI+） under multiple reaction monitoring（MRM） mode,and analyzed quantitatively by the external standard method.The calibration curves were linear in the concentration range of 0.1-20.0 mg/L for three compounds with correlation coefficients（r2） more than 0.995.The limits of detection（LODs） of urea,biruet and dicyandiamide were 0.03,0.05,0.01 mg/L,respectively,and their limits of quantitation（LOQs） were 0.08,0.10,0.03 mg/L,respectively.The average recoveries for urea,biruet and dicyandiamide at spiked concentration levels of 5.0,10.0,20.0 mg/kg were in the range of 70%-99% with relative standard derivations（RSDs） of 0.42%-8.0%.The method was simple,sensitive and accurate,and was suitable for the determination of urea,biruet and dicyandiamide residue in food samples.关键词：HPLC-MS/MS;urea;biruet;dicyandiamide;food
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发布时间： - 摘要：Based on the molecular alcohol aqueous two-phase system and the ionic liquid aqueous two-phase system,the new method of using n-propanol and hydrophilic ionic liquid（1-butyl-3-methylimidazolium tetrafluoroborate,［Bmim］BF4 ） with （NH4）2SO4 binary aqueous two phase system for the extraction of doxycycline hydrochloride was developed.The influence factors on partition behaviors of doxycycline hydrochloride were studied,including concentration of （NH4）2SO4,n-propanol consumption,pH value,concentration of ionic liquid and doxycycline hydrochloride.The results showed that when using pH value of 4.0-5.0,（NH4）2SO4 concentration of 34% and doxycycline hydrochloride concentration between 25-95 mg/L,the extraction rate and distribution coefficient of doxycycline hydrochloride will be up to 90.26%-95.71% and 62.452-149.401,respectively.关键词：ionic liquid;n-propanol;ammonium sulphate;doxycycline hydrochloride;aqueous two phase extraction
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发布时间： - 摘要：A method based on on-line enrichment technique and diffuse reflection near infrared spectroscopy(DRNIRS) was developed to detect rapidly trace plasticizer diisooctylphthalate(DEHP) in drink.DEHP solutions were passed through and concentrated with the polyethersulfone(PES) membrane and then the surface of the membrane was detected directly to collect diffuse reflection NIR(DRNIR) spectra.The wavenumber regions of 4 420-4 060,4 700-4 540,6 040-5 600 cm-1 were selected to build calibration models according to the transmission NIR spectrum of DEHP.The original spectral data were pretreated by multiplicative scattering correction(MSC),first derivative,second derivative,multiplicative scattering correction combined with first derivative and multiplicative scattering correction combined with second derivative，respectively.Meanwhile，partial least squares(PLS) calibration models with leave-one-out cross validation were established，and samples in the prediction dataset were predicted by the calibration models.The results demonstrated that the predictive results of the PLS calibration models were the best when the spectral data were pretreated by first derivative，and the latent variable number was 7.The root mean squared error of calibration(RMSEC) for the calibration samples was 0.188 7 mg/L，and the root mean squared error of prediction(RMSEP) for the prediction samples was 0.232 4 mg/L with mean relative error(MRE) of 6.29% in the DEHP mass concentration range of 0.5-5.0 mg/L.关键词：near infared spectroscopy;polyethersulfone membrane;diffuse reflection;diisooctylphthalate;drink;membrane enrichment technique
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发布时间： - 摘要：A fluorescence reagent quinoxaline-2,3-dicarboxaldehyde was firstly applied in the separation of amino acids by high performance liquid chromatography(HPLC).The reaction of primary amine amino acids with fluorescence reagent was studied in detail.The best conditions for the reaction:buffer:pH 9.5 100 mmol/L borate,a mole ratio of 2 mercapto ethanol,fluorescence reagent and amino acid:9∶3∶1,reaction time:5 min at room temperature.Under the optimal conditions,seventeen derivatives were detected with fluorescence detector after separation on a C18 column by gradient elution.The calibration curves were linear over the range of 0.01-1.00 mmol/L for all derivatives,with detection limits of 0.02-0.07 μg/L.This method was simple,rapid and sensitive,and was used for the measurement of the concentration of amino acid in ophiopogon of the Chinese traditional medicines with satisfactory results.关键词：Quinoxaline-2,3-dicarboxaldehyde;fluorescence-reagent;amino-acids;high performance liquid chromatography;fluorescent derivation
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发布时间： - 摘要：A fingerprint analysis method was developed for the quality control of Wanglaoji Guangdong herbal tea granule(GHTG)by ultra high performance liquid chromatography(UHPLC).The samples were extracted for 30 min by ultrasonic extraction using methanol as solvent.UHPLC separation was performed on a Waters ACQUITY HSS T3 C18(3.0 mm× 150 mm，1.8 μm) column by gradient elution with 0.5% formic acid-acetonitrile as mobile phase，at the temperature of 35 ℃ and a flow rate of 0.8 mL/min.A good separation of 28 common peaks was achieved within 18 min，and 4 of them were confirmed by reference substances.Similarity evaluation was performed by a professional software named Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(Version 2004A)，and the similarity among 23 batches of samples was no less than 0.95.The principal component analysis(PCA)also showed that the 23 batches of samples were located in one area.The results of similarity evaluation and PCA confirmed that the quality of Wanglaoji GHTG was stable，and the developed fingerprint analysis was fast，efficient and robust for the quality control of Wanglaoji GHTG.关键词：ultra high performance liquid chromatography;fingerprint;similarity evaluation;principal component analysis;Guangdong herbal tea granule;quality control
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发布时间： - 摘要：To investigate the role of iASPP in human ovarian cancer progression,the expression levels of iASPP in 56 pairs of ovarian cancer tissues and the matched tissues were examined using quantitative real-time PCR.Receiver operating characteristic(ROC) analysis was performed to further evaluate the clinical value of iASPP mRNA expression for the prediction of ovarian cancer.The iASPP gene expression could be firstly silenced by an iASPP-siRNA interference method in vitro.Then,the biological impact was investigated by Hoechst 33342 and CCK-8 assay in ovarian cell line OVCA420.Comparing with the adjacent tissues,it showed an over expressed iASPP in human ovarian cancer tissues.Down regulation of siRNA mediated by iASPP resulted in inhibited proliferation and increased apoptosis of ovarian cancer cell line OVCA420.According to the results,iASPP,which showed over-expression in the progression of ovarian cancer,could be considered as a target for ovarian cancer therapy.Moreover,iASPP mRNA could be a candidate marker for the diagnosis of ovarian cancer.关键词：iASPP;ovarian cancer;RT-PCR;RNA interference
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发布时间： - 摘要：Nanoparticle-based colorimetric sensing assays have recently attracted considerable attention in diagnostic application due to their simplicity and versatility.The key to establish nanoparticle-based colorimetric sensing assay is the control of nanoparticle dispersion and aggregation by using analytes of interest.Consequently，the color of the solution is the central in the design of such systems.This paper introduced briefly the physical phenomenon (i.e.colors) associated with nanoparticles and their aggregation， discussed the interparticle forces of nanoparticles，and described the modulation of nanoparticle stability and aggregation，which utilized both interparticle crosslinking and noncrosslinking aggregation mechanisms.The applications of nanoparticle-based colorimetric sensing assay in detecting heavy metal ions and biomolecules were reviewed，and its prospect was put forward.关键词：nanoparticles;colorimetric;heavy metal ions;biomolecules;chemical sensing;biological detection;review
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发布时间： - 摘要：Time-of-flight mass spectrometry（TOF-MS） is a new mass spectrometric technology，with the advantages of wide mass range，high sensitivity，high resolution，accurate mass analysis and high analysis speed.This artical introduces the basic principles and performance characteristics of TOF-MS，and summarizes the application progress of TOF-MS in the high-throughput screening and confirmatory analysis of food contaminants and their metabolites.关键词：chromatography;time-of-flight mass spectrometry（TOF-MS）;food;contaminant;trace analysis;application progress
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