1.ProteinsareTCAprecipitatedandwashedwithacetone,thendried.2.TheCNBrshouldbebroughttoroomtemperatureinthehoodandusedONLYinthehood.Extremelytoxic!3.DissolveasmallamountofCNBrin70%TFA,theexactamountisnotcritical.Oneortwocrystalsshouldbefine,althoughweighingthisreagentisNOTrecommended.PlacetheutensilusedindilutebleachtoneutralizetheresidualCNBr.4.Redissolvetheprecipitatedproteinin100microlitersofCNBr/TFAsolution,closetube.5.Digestionoftheproteinwilltakeabout36to72hoursatroomtemperature.6.DrythesamplesbySpeedvacwithheatforanhour.BeverycarefuloflingeringfumeswhenremovingsamplesfromtheSpeedvac.7.Redissolvethedigestedproteininwaterorotherbuffer.Thesesamplesaresomewhatacidicandshouldbeneutralizedwith1MTris8.0beforeloADIngtoSDSPAGE.