PAGE膠濃度交聯(lián)度與分子大小

產品信息產品名稱產品編號規(guī)格價格（元）40%Acr-Bis(19:1)20303ES76500ml220.0040%Acr-Bis(29:1)20304ES76500ml220.0040%Acr-Bis(37.5:1)20305ES76500ml220.00產品描述Acr-Bis常用于配制丙烯酰胺凝膠（PAGE交），包括SDS交等，可以用于蛋白或核酸的分離。聚丙烯酰胺凝膠是由丙烯酰胺（acrylamide，簡稱Acr）和交聯(lián)劑甲叉雙丙烯酰胺（N,N-methylenebisacrylamide、簡稱Bis）在催化劑的作用下，通過自由基引發(fā)聚合反應，形成不帶電荷、且具有分子篩性質的網狀結構。其孔徑大小由聚合鏈的長度和交聯(lián)度（交叉連接的程度）所決定。聚合鏈的長度與丙烯酰胺的濃度有尖，交聯(lián)度由 Acr與Bis的相對比例決定，調節(jié)單體丙烯酰胺與交聯(lián)劑（Bis）的濃度比例，可形成具有不同交聯(lián)度的網狀聚合物。其中 Bis的濃度愈低，凝膠的孔徑愈大，適用于分離較大的分子；Bis的濃度愈高，網孔越小，分辨率越高，越有利于分離較小的分子。40%Acr-Bis(19:1) 即為含40%acrylamide-bisacrylamide的水溶液，其中acrylamide和bisacrylamide的比例為19:1°40%Acr-Bis(29:1) 即為含40%acrylamide-bisacrylamide的水溶液，其中acrylamide和bisacrylamide的比例為29:1°40%Acr-Bis(37.5:1)即為含40%acrylamide-bisacrylamide的水溶液，其中acrylamide和bisacrylamide的比例為37.5:1。運輸與保存方法冰袋(wetice)運輸。4°C避光保存。注意事項1)Acr-Bis具有一定神經毒」性，使用時請注意適當防護。2） 為了您的安全和健康，請穿實驗服并戴一次性手套操作。ThePolyacrylamideMatrixAmflWfliurnPtt&u-rlias*FAcrylanwleTh*Thepolymerizationofapolyacrylamidematrixwithmethylenebisacrylamidecross-1inking.Polyacrylamidegelsareformedbythepolymerizationofacrylamideinaqueoussolutioninthepreseneeofsmallamountsofabifunctionalcrosslinker.Thecrosslinkerisusuallymethylene:bisacrylamide(bis,orMBA)?Thecopolymerizationofacrylamidewithmethylenebisacrylamideproducesamesh-likenetworkinthreedimensions,consistingofacrylamidechainswithinterconnectionsformedfromthemethylenebisacrylamide.Avarietyofcrosslinkersareavailableinadditiontobis.Theseineludepiperazinediacrylate(PDA),N,N'-bisacrylylcystamine(BAC),andN,N'-diallyltartardiamide(DATD).PDAisusedtoreducesilverstainbackgroundsinSDSgels.BACandDATDarebothdisruptablecross-linkerswhichenablegelstobesolubilized.HOOFiN?dtaldyllalardlamicleV-/PiperazinedkacryUleilPDAiHOOFiN?dtaldyllalardlamicleV-/PiperazinedkacryUleilPDAiBAC,DATD,andPiperazinediacrylatearesometimesused

asthecross-1inkersinpolyacrylamidegelstovarythe

physicalorchemicalpropertiesofthegel.Fordiscussionsofthecompositionofpolyacrylamidegels,astandardnomenclaturehasbeenwidelyadopted.Inthisnomenclature,Trepresentsthetotalpercentageconcerntration(w/v)ofmonomer(acrylamidepluscrosslinker)inthegel.ThetermCreferstothepercentageofthetotalmonomerrepresentedbythecrosslinker.Forexample,an8%,19:1(acrylamide/bisacrylamide)gelwouldhaveaTvalueof8%andaCvalueof5%.Upontheintroductionofcatalyst,thepolymerizationofacrylamideandmethylenebisacrylamideproceedsviaafree-radicalmechanism.ThemostcommonsystemofcatalyticinitiationinvolvestheproductionoffreeoxygenradicalsbyammoniumpersulfateinthepreseneeofthetertiaryaliphaticamineN^N^N^N'-tetramethylethylenediamine(TEMED) .AnothercatalyticsysteminvolvesthegenerationoffreeradicalsviaaphotochemicalprocessusingaverysmallamountofriboflavininthepreseneeofTEMED.Inbothcatalyticsystems,thepreseneeofexcessoxygenwillinhibitthepolymerizationelongationprocessandcanleadtoshorteraveragechainlength.Forthisreason,ifthecastingsolutionhasbeenexcessivelyagitated,deaerationundervacuumwithamagneticstirrerissuggestedpriortoadditionofinitiators.Forcertainapplications,polyacrylamidehasdefiniteadvantagescomparedtoagarose.Inanagarosegel,theporesizeislarge,somolecularsieving,i.e.separationbysize,willnotoccurforsmallerDNAfragmentsandmostproteins.Additionally,byalteringthetotalconcentrationofmonomerinthegelandtheratioofacrylamidetobis,theporesizewithapolyacrylamidegelcanbealteredinareproduciblemanner.Thesmallandreproducibleporesizeinpolyacrylamidegelsresultsinsuperiorresolution:a0.1%differeneeinsize(1basediffereneeina1kbmolecule)canbedetected.Also,becauseacrylamideandbisaresyntheticchemicals,therearevirtuallynobatchtobatchdifferences(Itshouldbementionedthatbatchtobatchdifferenceswithagaroseareovercomewiththehighestqualityagaroses,suchasNationalDiagnosties'AquaPoragaroses).ControloftheporesizeofapolyacrylamidegelisaccomplishedbychangingtheTandCvalues.WithincreasingT,theporesizedecreasesinanearlylinearrelationship.Higherpercentagegels(higherT),withsmallerpores,areusedtoseparatesmallermolecules.TherelationshipofCtoporesizeismorecomplex.Generally,theminimumporesizeoccurswhenCisabout5%(a19:1gel)?DecreasingCresultsinamoreopenporestructurebecausetherearefewercrosslinkermolecules.IncreasingCbeyond5%alsoincreasestheporesize.Thisappearstobebecauseofnonhomogeneousbundlingofstrandsinthegel.ResearchershavesettledonCvaluesof5.0%(19:1acrylamide/bis)formostformsofdenataringDNAandRNAelectrophoresisand3.3%(29:1)formostnativeDNAandRNAgels.ForSDSelectrophoresisofproteins,thestandardCvaluethathasbeenadoptedis2.6%(37.5:1)?Thetablebelowgivesrecommendedacrylamide/bisratiosandgelpercentagesfordifferentmolecularsizeranges.PolyacrylamideGelSolutionsRecommendedappplicationsforeachf