简介:Thispaperreportsthedevelopmentandvalidationofanassayforthedeterminationofacetonitrileintherecycledmobilephaseusinghighperformanceliquidchromatography(HPLC).Themethodisbasedonthattheretentioninreversed-phaseliquidchromatographyincreaseswithdecreasingconcentrationoforganicphaseinthemobilephase.Thenaturallogarithmofthecapacityratioforagivensoluteislinearlyrelatedtothevolumefractionoftheorganicmodifierinthemobilephase.Fordimethylphthalateanddiethylphthalate,thelinearityrangeis30%―60%,andforbiphenylandterphenyl,therangeis60%―95%.Precisionvalues(RSD)wereboth<1%andtheaccuracy(RE)wasintherangeof±1%.Theassaywassuccessfullyappliedtothedeterminationofacetonitrileconcentrationofrecycledmobilephaseafterthedistillationofthecolumneluentinourlaboratory.
简介:TheroleplayedbyDNAinmolecularbiologyisclearlyrecognizedtobevitaltolifeonthisplanet.8-oxo-7,8-dihydro-2deoxyguanosine(=8-OHdG),isprobablythemostimportantproductof"oxidativestress”inDNA.ItsconcentrationinDNAis,infact.aquantitativeanalysisofthedegreeofDNAdamagethatanorganismhasundergone.Duetotheimportanceof8-OHdGofnucleicacidginmutagenesis,carcinogenesisandaging,numerouschemicalandbiologicalinvestigationshavebeenmadeonthissubjectinthepasttime.Kuchinoandco-workershavefoundthat8-OHdGresidueinDNAismisreadingduringtheprocessofDNAreplication.Recently,somereportshavebeenpresentedonhigh8-OHdGlevelsinpatientssufferingfromvariousdiseasessuchaschronichepatitis,Fanconisanemia,diabetesmellitusandHelicobacterpyloriinfections.Asaresult,8-OHdGisausefulmarkerforthestudyofDNAdamagearisingfromreactiveoxygenspeciesandisofgreatsignificanceforcancerresearch.The8-OHdGlevelsinDNAcanhelpunderstandthemechanismofcarcinogensandleadtomoreeffectivetreatmentsformanydifferenttypesofcancer.Forthesereasons,ananalysisof8-OHdGwithquickness,lowcostandhighaccuracyisrequired.
简介:Arapidandeffectivemethod,solidphaseextractioncoupledwithhighperformanceliquidchromatography(SPE-HPLC),wasappliedtotheseparationandanalysisofginsenosides.WatersOASISHLBwasusedforconcentratingandpurifyingsamplesandAlltimaC_(18)(53mm×7mm,3μm)chromatographycolumnwasusedforseparatingginsenosideRg_1,Re,Rb_1,Rc,Rb_2andRd.Theseginsenosideswereanalyzedwithin20mininourgradientelutionprocessandtheequilibriumtimeofthechromatographycolumncostonly5min.Moreover,therewasnoobviousbaselinedriftinourexperiment.Thismethodwasusedtoanalyzethecontentsofginsenosidesindifferentginsengproductsforqualitycontrol.Fourginsengproductswerestudied,includingtwokindsofcapsules,onekindoftabletandonekindofinjection.Theresultsshowthatthemethoddevelopedinthispaperhadgoodaccuracy,linearityandprecision.Therefore,thismethodcouldbeappliedinqualitycontrolofginsengproducts.
简介:本文将一个关于两个不交国的单点粘合的图的LPlaCe谱的受控定理推广到了两个国的多点粘合何形;同时证明了相同的结果对目的Q一回也成立。
简介:Apartiallysubstitutedβ-cyclodextrinchiralstationaryphasewaspreparedbythereactionofphenylisocyanate.TheenantiomersofaseriesofO,O-diethyl(p-methylbenzenesulfonamido)-aryl(oralkyl)-methylphos-.phonateswerestudiedonthepreparedphenylcarbamatederivativeβ-cyclodextrinbondedphaseandacommercial(S)-(.+)-l-(l-naphthyl)ethylcarbamatederivativeβ-cyclodextrinbondedphaseonnormalphasechromato-graphiccondition.Resultsshowthatthepreparedphenylcarbamatederivativeβ-cyclodextrinbondedphasehasbetterenantiomericselectivitytotheseriesofcompounds.Achiralrecognitionmechanismwassuggestedfortheseparationofthesenovelorganicphosphorusenantiomers.
简介:建立了多反应监测法测定化妆品中α-萘酚和β-萘酚2种禁用着色剂的高效液相色谱-二级质谱联用(HPLC-MS/MS)的分析方法.针对几类美妆用品进行了样品前处理、色谱分离条件和二级质谱条件的研究.色谱条件经优化后确定:以常用的反相键合的十八烷基为固定相,以乙腈和水的二元流动相进行梯度洗脱,以配有电喷雾离子源的二级质谱为检测器等.考察了膏霜类、油状液体类和水类不同基质化妆品中两种萘酚异构体的加标回收率,标准偏差和变异系数.在0.05-10.0mg/L的范围内,2种目标物均有良好的线性关系,检测限(S/N≥10)均为0.2ng/g.6个样品的高、中、低3个标准添加水平下,回收率为81.95%-98.30%,相对标准偏差为0.0015%-0.078%,变异系数为0.83%-8.2%.样品中均未发现禁用着色剂萘酚的2种异构体.该方法可用于化妆品中α-萘酚和β-萘酚的检测.
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简介:AnHPLCmethodforquantitativedeterminationofadrenalinehydrochlorideinjectionandnoradrenalinebitartrateinjectionwasestablishedandvalidatedwithasubstituteforthereferencesubstance.Phenylephrinehydrochloridewasselectedasthesubstituteforthereferencesubstanceofadrenalineandnoradrenalinebitartrate.Thecorrectionfactorofphenylephrinehydrochloridewithrespecttothereferencesubstanceofadrenalineandnoradrenalinebitartratewasdeterminedunderdefinedconditions.Adrenalinehydrochlorideinjectionandnoradrenalinebitartrateinjectionwerequantifiedbyassayingphenylephrinehydrochlorideandacorrectfactor.TheresultsindicatethattheHPLCmethodwiththesubstituteforreferencesubstancewasreliableandfeasibleforquantitativedeterminationofdrugs.
简介:Fivechiralstationaryphases(CSPs)wereusedtoseparatetheenantiomersofaseriesofO,O-diethyl(p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates.Achiralrecognitionmechanismwaspresentedtoexplaintheresolutionofthesecompounds.ResultsshowthatCSPwithstrongπ-acceptor3,5-dinitrobenzoylgroupandhighsterichindrancehasthebestresolutionabilityinchiralseparationofO,O-diethyi(p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates.WhenaCSPhasjustastrongπ-acceptor3,5-dinitrobenzoylorhighsterichindranceitdoesnothavegoodchiralresolutionability.ThechiralrecognitionismoredifficultwhentheCSPhasmorethanoneasymmetriccenter.
简介:Thesynthesisandspectrophotometricpropertiesof2-(6-methyl-2-benzothiazolylazo)-5-diethylaminophenol(MBTAE),andtheuseofitasaprecolumnderivatizingreagenttoseparateCo(Ⅱ),Ni(Ⅱ),Rh(Ⅲ)andIr(Ⅳ)complexesbyHPLCarediscussed.Whenthemobilephaseconsistsofmethanol/water(90/10Ⅴ/Ⅴ),acetatebufferwithpH4.0and5×10-5mol/LEDTAsolution,thefourcomplexesCanbeseparatedwithin9minonODScolumn.Thedetectionlimits(20μLsamplesize)are0.059ppb,0.062ppb,0.053ppband0.049ppbforCo(Ⅱ),Rh(Ⅲ),Ni(Ⅱ)andlr(Ⅳ)respectivelyatasignal-to-noiseratioof3.
简介:Aretentionpredictionsystem(RPS)ofsevenO-ethylN-isopropylphosphoro(thioureido)-thioatesinreversedphaseHPLCwasinvestigated.Thesystemisbasedonthesolventselectivitytriangleconcept.Threemolecularstructureparameters(hydrophobicityⅡ,substituentlengthL,andsubstituentmaximumwidthB5)wereusedtodescribethequantitativestructure-retentionrelation-ships.Withthesequantitativerelationships,theretentionbehavioursofothereighthomologsfordifferentmobilephasecompositionwerepredicted.Thepredictedvalueswereconsistentwiththemeasuredvalueswithinrelativeerrorof10%,whichmeansthatitispossibletoapplythereportedmethodtopredictretentionvaluesforqualitativepurposesfordifferentmobilephasecompositions.
简介:采用液相色谱-蒸气发生-原子荧光光谱联用技术(HPLC-HG-AFS,以下简称LC-AFS)对水产动植物样品中无机砷进行测定。藻类中以紫菜、海带、羊栖菜为研究对象,水产动物中以贝类、鱼类、虾类为研究对象,实验中研究了流动相的种类和浓度、提取剂的种类和浓度,并通过正交实验法确定了最佳提取温度、提取时间、氧化时间。在最优的实验条件下运用等度洗脱的方式测定了样品中无机砷的含量,并对方法的有效性进行了验证,结果表明,三价砷、五价砷、一甲基砷和二甲基砷在5-100μg/L范围内线性关系良好;同时对不同海产品进行加标回收实验,结果表明,各组分的加标回收率在80%-105%。平行样品测定结果的相对标准偏差在2%-6%。说明液相色谱-原子荧光光谱联用法很好地解决了水产品中砷形态测定的问题,尤其对无机砷的测定提供了非常有效的方法。方法简便、准确、设备价格低廉,完全可用于水产动植物产品中无机砷的测定。