
Description:

Rapid,sensitiveandpreciseprobe-basedqPCRdetectionandquantitationoftargetDNAandCDNAsequences.
Probe-basedquantitativePCR(qPCR)usesreal-timefluorescencereleasedupon5´→3´exonucleasecleavageofaquenched,target-specificprobetomeasureDNAamplificationateachcycleofaPCR.Atapointwherethefluorescencesignalissignificantlydetectableoverthebackgroundfluorescence,aquantificationcycleorCqvaluecanbedetermined.Cqvaluescanbeusedtoevaluaterelativetargetabundancebetweentwoormoresamplesortocalculateabsolutetargetquantitiesinreferencetoanappropriatestandardcurve,derivedfromaseriesofknowndilutions.
TheNEBLunaUniversalProbeqPCRMasterMixisa2Xreactionmixoptimizedforreal-timeqPCRdetectionandquantitationoftargetDNAsequencesusinghydrolysisprobes.ItcontainsHotStartTaqDNAPolymeraseandhasbeenformulatedwithauniquepassivereferencedyethatiscompatIBLeacrossavarietyofinstrumentplatforms(includingthosethatrequireahighorlowROXreferencesignal).ItalsofeaturesdUTPforcarryoverpreventionandanon-fluorescent,visibledyetomonitorreactionsetup.ThisdyedoesnotspectrallyoverlapfluorophorescommonlyusedforqPCRandwillnotinterferewithreal-timedetection.
Themastermixformulationissuppliedat2XconcentrationandcontainsallPCRcomponentsrequiredforamplificationandquantitationofDNAexceptprimers/probesandDNAtemplate.GenomicDNAorcDNAofinterestcanbequantitatedwithLunaqPCRandexistingaswellascommercialqPCRassayprimer/probesequencescanbeused.



LearnmoreaboutourcomprehensiveqPCR/RT-qPCRtestingand“dotsinboxes”datavisualization
Notes:
AssayDesignTheuseofqPCRprimerdesignsoftware(e.g.,Primer3)maximizesthelikelihoodofamplificationsuccesswhileminimizingnonspecificamplificationandprimerdimers.TargetswithbalancedGC/ATcontent(40–60%)tendtoamplifyefficiently.Wherepossible,entersufficientsequencearoundtheareaofinteresttopermitrobustprimerdesignandusesearchcriteriathatpermitcross-referenceagainstrelevantsequencedatabases(toavoidpotentialoff-targetamplification).ForcDNAtargets,itisadvisabletodesignprimersacrossknownsplicingsitesinordertopreventamplificationfromgenomicDNA.Conversely,primersdesignedtotargetintronicregionscanensureamplificationexclusivelyfromgenomicDNA.PrimerandProbeConcentrationFormosttargets,afinalconcentrationof400nMforeachprimerwillprovideoptimumperformance.Ifneeded,primerconcentrationscanbeoptimizedbetween200–900nM.Probeshouldbeincludedat200nMforbestresults.Probeconcentrationcanbeoptimizedintherangeof100–500nMifoptimizationofperformanceortargetfluorescencelevelisdesired.MultiplexingTodetectorquantitatemultipletargetsinthesameLunareaction,selectdifferentfluorophorescorrespondingtoseparatedetectionchannelsofthereal-timeinstrument.Include400nMofforwardandreverseprimerand200nMprobeforeachtargettobedetectedinthereaction,andadjustconcentrationsifnecessarybasedonperformance(primer200–900nM,probe100–500nM).WhenloADIngqPCRprotocolontothereal-timeinstrument,besuretoselecttheappropriateopticalchannels,assomeinstrumentshaveasinglechannelrecordingmodethatwouldpreventmultiplexdatacollectionandanalysis.ForROX-dependentinstruments,avoidROX-labeledprobes.Thefunctionalityoftheprimerandprobesetsshouldbetestedindividuallybeforeattemptingamultiplexreaction.Whendeterminingwhichfluorophorestoincludeinamultiplexreaction,besuretochoosecompatiblereporterdyesandquenchersthathavewellseparatedfluorescencespectraorexhibitminimaloverlap.AmpliconLengthToensuresuccessfulandconsistentqPCRresults,itisimportanttomaximizePCRefficiency.AnimportantaspectofthisisthedesignofshortPCRamplicons(typically70–200bp).Someoptimizationmayberequired(includingtheuseoflongerextensiontimes),fortargetsthatexceedthatrange.TemplatePreparationandConcentrationLunaqPCRiscompatiblewithDNAsamplespreparedthroughtypicalnucleicacidpurificationmethods.PreparedDNAshouldbestoredinanEDTA-containingbuffer(e.g.,1XTE)forlong-termstability,anddilutionsshouldbefreshlypreparedforaqPCRexperimentbydilutionintoeitherTEorwater.Generally,ausefulconcentrationofstandardandunknownmaterialwillbeintherangeof106copiesto1copy.ForgDNAsamplesfromlargegenomes(e.g.,human,mouse)arangeof50ng–1pgofgDNAistypical.Forsmallgenomes,adjustasnecessaryusing106 –1copyinputasanapproximaterange.Notethatforsinglecopydilutions,somesampleswillcontainmultiplecopiesandsomewillhavenone,asdefinedbythePoissondistribution.ForcDNA,usetheproductofareactioncontaining1μg–0.1pgstartingRNA.cDNAdoesnotneedtobepurifiedbeforeadditiontotheLunareactionbutshouldbedilutedatleast1:10intotheqPCR.ROXReferenceDyeSomereal-timeinstrumentsrecommendtheuseofapassivereferencedye(typicallyROX)toovercomewell-to-wellvariationsthatcouldbecausedbybubbles,smalldifferencesinvolume,andautofluorescencefromdustorparticulatesinthereaction.TheLunaUniversalProbeqPCRMasterMixisformulatedwithauniversalreferencedyethatiscompatiblewithavarietyofqPCRinstrumenttypes,includingthosethatusenopassivereferencenormalizationandthosethatusealoworhighconcentrationofpassivereferencedye(ROX).Therefore,noadditionalcomponentsarerequiredtoensurecompatibilitywiththeseinstruments.CarryoverContaminationPreventionqPCRisanextremelysensitivemethod,andcontaminationinnewqPCRassayswithproductsfrompreviousamplificationreactionscancauseavarietyofissuessuchasfalsepositiveresultsandadecreaseinsensitivity.Thebestwaytopreventthis“carryover”contaminationistopracticegoodlaboratoryproceduresandavoidopeningthereactionvesselpostamplification.However,toaccommodatesituationswhereadditionalanti-contaminationmeasuresaredesired,theLunaUniversalProbeqPCRMasterMixcontainsamixtureofdUTP/dTTPthatresultsintheincorporationofdUintotheDNAproductduringamplification.PretreatmentofqPCRexperimentswithuracilDNAglycosylase(UDG)willeliminatepreviously-amplifieduracil-containingproductsbyexcisingtheuracilbasetoproduceanon-amplifiableDNAproduct.TheuseofaThermolabileUDGisimportant,ascompleteinactivationoftheUDGisrequiredtopreventdestructionofnewlysynthesizedqPCRproducts.Toenablecarryoverprevention,0.025units/μlAntarcticThermolabileUDG(NEB#M0372)shouldbeaddedtothereactionmix.Tomaximizeeliminationofcontaminatingproducts,setuptheqPCRexperimentsatroomtemperatureorincludea10minuteincubationstepat25°Cbeforetheinitialdenaturationstep.ReactionSetupandCyclingConditionsDuetothehotstartnatureofthepolymerase,itisnotnecessarytopreheatthethermocyclerpriortouseorsetupreactionsonice.For96-wellplates,werecommendafinalreactionvolumeof20μl.For384-wellplates,afinalreactionvolumeof10μlisrecommended.Whenprogramminginstrumentcyclingconditions,ensureaplatereadisincludedattheendoftheextensionstep,andadenaturation(melt)curveaftercyclingiscompletetoanalyzeproductspecificity.Amplificationfor40cyclesissufficientformostapplications,butforverylowinputsamples45cyclesmaybeused.ebiomall.com






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制备抗体都需要进行纯化处理
多抗,稀释度更大,特异性相对较差,容易出现多条带。
兔的单克隆抗体和鼠的单克隆抗体在使用上不会有什么区别。
用来很多抗体,许多时候觉得单抗多抗也未必是理论上那样的。单抗做不好的也有,多抗条带唯一且清晰的也有。
而且很多蛋白的抗体未必有那么多的选择。
1.单克隆抗体的优点:
(1)杂交瘤可以在体外“永久”地存活并传代,只要不发生细胞株的基因突变,就可以不断的生产高特异性、高均一性的抗体.
(2)可以用相对不纯的抗原,获得大量高度特异的、均一的抗体.
(3)由于可能得到“无限量”的均一性抗体,所以适用于以标记抗体为特点的免疫学分析方法,如IRMA和ELISA等.
(4)由于单克隆抗体的高特异性和单一生物学功能,可用于体内的放射免疫显像和免疫导向治疗.
2.单克隆抗体的局限性:
(1)单克隆抗体固定的亲和性和局限的生物活性限制了它的应用范围.由于单克隆抗体不能进行沉淀和凝集反应,所以很多检测方法不能用单克隆抗体完成.
(2)单克隆抗体的反应强度不如多克隆抗体.
(3)制备技术复杂,而且费时费工,所以单克隆抗体的价格也较高.
说得简单点就是,细胞核是原封不动的,没有重组过,而细胞核外的东西是很多别的细胞中提取出来的并组合起来的。这样的混合体淋巴细胞产生的抗体具有很强的嵌合能力,针对性比一般的抗体强,但是它的来源没变,所以称之为混合单克隆抗体

