描述
Labeleddextransarehydrophilicpolysaccharidesmostcommonlyusedinmicroscopystudiestomonitorcelldivision,trackthemovementoflivecells,andtoreportthehydrodynamicpropertiesofthecytoplasmicmatrix.Thelabeleddextraniscommonlyintroducedintothecellsviamicroinjection.
DextranSpecifications:
• Label(Ex/Em):Tetramethylrhodamine(555/580)
• Size:70,000MW
• Charge:Anionic
• Fixable:FixableviaLysine
HighManufacturingStandardsofMolecularprobes®Dextrans
Weoffermorethan50fluorescentandbiotinylateddextranconjugatesinseveralmolecularweightranges.Dextransarehydrophilicpolysaccharidescharacterizedbytheirmoderate-to-highmolecularweight,goodwatersolubility,andlowtoxicity.Theyalsogenerallyexhibitlowimmunogeniticy.DextransareBIOLOGicallyinertduetotheiruncommonpoly-(α-D-1,6-glucose)linkages,whichrenderthemresistanttocleavagebymostendogenouscellularglycosidases.
Inmostcases,MolecularProbes®fluorescentdextransaremuchbrighterandhavehighernegativechargethandextransavailablefromothersources.FurThermore,weuserigorousmethodsforremovingasmuchunconjugateddyeaspractical,andthenassayourdextranconjugatesbythin-layerchromatographytohelpensuretheabsenceoflowmolecularweightcontaminants.
AWideSelectionofSubstituentsandMolecularWeights
MolecularProbes®dextransareconjugatedtobiotinorawidevarietyoffluorophores,includingsevenofourAlexaFluor®dyes(MolecularProbesdextranconjugates–Table14.4)andareavailableinthesenominalmolecularweights(MW):3,000;10,000;40,000;70,000;500,000;and2,000,000daltons.
DextranNetChargeandFixABIlity
Weemploysuccinimidylcouplingofourdyestothedextranmolecule,which,inmostcases,resultsinaneutraloranionicdextran.ThereactionusedtoproducetheRhodamineGreen™andAlexaFluor® 488dextransresultsinthefinalproductbeingneutral,anionic,orcationic.TheAlexaFluor®,CascadeBlue®,luciferyellow,fluorescein,andOregonGreen® dextransareintrinsicallyanionic,whereasmostofthedextranslabeledwiththezwitterionicrhodamineB,tetramethylrhodamine,andTexasRed® dyesareessentiallyneutral.Toproducemorehighlyanionicdextrans,wehavedevelopedaproprietaryprocedureforaddingnegativelychargedgroupstothedextrancarriers;theseproductsaredesignated"polyanionic"dextrans.
Someapplicationsrequirethatthedextrantracerbetreatedwithformaldehydeorglutaraldehydeforsubsequentanalysis.Fortheseapplications,weoffer"lysine-fixable"versionsofmostofourdextranconjugatesoffluorophoresorbiotin.Thesedextranshavecovalentlyboundlysineresiduesthatpermitdextrantracerstobeconjugatedtosurroundingbiomoleculesbyaldehyde-mediatedfixationforsubsequentdetectionbyimmunohistochemicalandultrastructuraltechniques.Wehavealsoshownthatallofour10,000MWAlexaFluor®dextranconjugatescanbefixedwithaldehyde-basedfixatives.
KeyApplicationsUsingLabeledDextrans
Thereareamultitudeofcitationsdescribingtheuseoflabeleddextrans.Someofthemostcommonusesinclude:
• Neuronaltracing(anterogradeandretrograde)inlivecells
• Celllineagetracinginlivecells
• Neuroanatomicaltracing
• Examiningintercellularcommunications(e.g.,ingapjunctions,duringwoundhealing,andduringembryonicdevelopment)
• Investigatingvascularpermeabilityandblood–brainbarrierintegrity
• Trackingendocytosis
• Monitoringacidification(somedextran–dyeconjugatesarepH-sensitive)
• Studyingthehydrodynamicpropertiesofthecytoplasmicmatrix
ForResearchUseOnly.Notintendedforanyanimalorhumantherapeuticordiagnosticuse.
ForResearchUseOnly.Notforuseindiagnosticprocedures.
规格
ProductSize: | 25mg |
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ShippingCondition: | RoomTemperature |
内容及储存
Storeinfreezer(-5to-30°C)andprotectfromlight.