Biocare Medical/4plus HRP Universal Detection/HP504 US/1000-slides

Streptavidinisaproteinthathassimilarbindingpropertiestoeggwhiteavidin.Itisisolatedfromstreptomycesavidinii.Streptavidinhasamolecularweightof60KDandhas4subunits.Eachsubunitcanbindonemoleculeofbiotin.Biotinisawatersolublevitamin.Streptavidinhasanextremelyhighbindingaffinity(Kd=10-15)forbiotin.Ithasprovenusefulinthedetectionofantigenscoupledwithbiotinylatedsecondaryantibodies.Thereareseveraladvantageswhenusingstreptavidinversusanavidincomplex(ABC).Incontrasttoavidin,streptavidinisnotglycosylatedandisthereforeunchargedatneutralpH(6.5versus10).Thislowersnonspecificbackgroundstaining.Streptavidinalsolackscarbohydratesidechainsthatmaybeanothercauseofnon-specificbackground.Anotherkeyadvantageofstreptavidinisthesignificantincreaseinsensitivity(probablyduetolesssterichindrance),thusfacilitatinganincreaseinoverallbindingcapacity.Finally,streptavidin-enzymeconjugatesaremuchmorestablethananABCcomplex.TheABCcomplexmustbefreshlymade30minutespriortouseandisstableonlyforafewdays.Incontrast,astreptavidin-conjugatecanbestoredforupto1-2years.Thereagentcomesinaready-to-useformat,thussavingtimeandpotentialmistakes.BIOCARE’S4plus™detectionsystemhasbeendevelopedtoprovideasignificantincreaseinstainingsensitivity.Thevastmajorityofprimaryantibodiescanbedilutedtwo-foldcomparedtoothercommerciallyavailabledetectionsystems.4plus™UniversalDetectionsystemcanbeusedwithbothmouseandrabbitprimaryantibodies.Afterlabelingtheantigenwithaprimaryantibody,auniversal,affinitypurified,biotinylatedsecondaryantibodyisaddedtobindtotheprimaryantibody.HorserADIshperoxidase(HRP)labeled-streptavidinisthenaddedtobindtothebiotinylatedsecondaryantibody.Achromogen/substrateisthenappliedandreactswithaspecificenzymetoproduceanintensecolorsignal.4plus™detectionsystemsworkwellwithparaffin-embeddedtissues,frozensectionsandcellpreparations.