Acetoxymethyl (AM) and Acetate Esters.pdfVIP免费

MAN0001771Revised:24–May–2010|G002Table1.Contentsandstorageinformation.ProductAmountConcentrationStorageStabilityPleaserefertoproductlabel•≤–20°C•Desiccated•Protectedfromlightor•≤–20°C•Desiccated(seethelabel)Whenstoredasdirected,productisstablefor6months.Acetoxymethyl(AM)andAcetateEstersIntroductionTheacetoxymethyl(AM)esterderivativesoffluorescentindicatorsandchelatorsmakeuponeofthemostusefulgroupsofcompoundsforthestudyoflivecells.Modificationofcarbox­ylicacidswithAMestergroupsresultsinanunchargedmoleculethatcanpermeatecellmembranes.Onceinsidethecell,thelipophilicblockinggroupsarecleavedbynonspecificesterases,resultinginachargedformthatleaksoutofcellsfarmoreslowlythanitsparentcompound.Frequently,hydrolysisoftheesterifiedgroupsisessentialforbindingofthetargetion.Insomecases(e.g.,calceinAM),theAMesteriscolorlessandnonfluorescentuntilhydrolyzed.Thispropertyisusefulindiagnosingspontaneoushydrolysisduringstorage.Acetategroups,usedonmanyfluorescentindicators,areanalogoustoAMestergroupsandshouldbetreatedsimilarly.GuidelinesforUsePreparingtheStockSolutionsAMoracetateestersshouldbereconstitutedonlyasrequiredusinghigh­quality,anhydrousdimethylsulfoxide(DMSO).Reagent­gradeDMSOshouldbestoredwellsealedunderargonornitrogen,anddesiccated;desiccantbeads(e.g.,molecularsieves)canbeusedforshort­termstorage.DissolutionofthepureAMoracetateestersinDMSOmaybeslow(particularlyinthe1mgsizes).Onceprepared,DMSOstocksolutionsofAMoracetateestersshouldpreferablybeusedwithinashorttimeperiodforoneseriesofexperiments.DMSOstocksolutionsmustbekeptanhydrous,sincethesolventwillreadilytakeupmoisture,leadingtodecompositionofthedye.Thesestocksolutionsshouldbestoredwellsealed,frozen,anddesiccated.ManyofourAMandacetateestersareavailableinsmallaliquots.Useoftheprealiquotedproductisstronglyrecommended.ItisadvisabletokeeptheAMesteroracetateesterinasconcentratedastockaspossiblesothatminimalamounts(ideally≤0.1%)ofDMSOarepresentintheloadingsolution.Acetoxymethyl(AM)andAcetateEsters|2UsingPluro...