b'Protein quantitationDetermining your samples protein concentrationbased on the compatibility with common substances in Protein quantitation is a necessary step before conductingthe sample (detergents, reducing agents, inhibitors, salts, analysis that compares one sample to another and tochaotropic agents) and the sensitivity needed. See the prevent under- or overloading of the gel. The choicetable below for the recommend assay based on common of which method to use for protein quantitation will belysis buffers.Recommended assays based on common lysis buffers If adding reducing agents or metal chelators Lysis/extraction bufferRecommended protein assay(e.g., DTT above 1 mM, EDTA above 10 mM) RIPA Lysis and Extraction BufferBCA protein assay Pierce BCA Protein Assay KitReducing (25 mM Tris-HCl, pH 7.6, 150 mM NaCl,Agent Compatible1% NP-40, 1% sodium deoxycholate, 0.1% SDS)Invitrogen Lysis Buffer Pierce BCA Protein Assay KitReducingPierce BCA Protein AssayReducing Agent (10 mM Tris, pH 7.4, 100 mM NaCl, 1 mM EDTA,Agent Compatible Compatible1 mM EGTA, 1 mM NaF, 20 mM Na4P2O7, 2 mM Na3VO4, 1% Triton X-100, 10% glycerol, 0.1% SDS, 0.5% deoxycholate)M-PER Mammalian ProteinBCA protein assay Pierce Coomassie Plus (Bradford) Assay KitExtraction ReagentB-PER Bacterial Protein Extraction Reagents BCA protein assay Pierce BCA Protein Assay KitReducing Agent CompatibleNE-PER Nuclear and CytoplasmicBCA protein assay Pierce Coomassie Plus (Bradford) Assay KitExtraction ReagentsGood to know TipBCA protein assays have a unique advantage overFor quantitation of low-volume or very dilute samples, Coomassie dyebased assays (Bradford assays), asfluorescent assays can provide working ranges down they are compatible with samples that contain up toto 10 ng/mL compared to 500 ng/mL for enhanced 5% surfactants (detergents), and are affected muchcolorimetric assays and 2,000 ng/mL for standard less by protein compositional differences, providingcolorimetric protocols.greater protein-to-protein uniformity and accuracy.Protein assay guide Thermo ScientificThermo ScientificThermo Scientific PierceThermo Scientific Pierce Rapid GoldPierce BCA ProteinBCA Protein AssayReducingPierce Coomassie Plus BCA Protein Assay Kit Assay Kit Agent Compatible Kit (Bradford) Assay KitOverview 5 min room-temperatureStandard BCA assay withReducing agentcompatibleImproved Bradford assay BCA assay large linear response BCA assay with linear responseMinimum sample volume 10 L 25 L 25 L 10 LWorking range 1252,000 g/mL 202,000 g/mL 1252,000 g/mL 1001,500 g/mLCompatibility Detergents Detergents Detergents and reducing agents Reducing agentsIncubation temperature RT 37C 37C RTAssay time 5 min 30 min 50 min 10 minAssay wavelength 480 nm 562 nm 562 nm 595 nmDownload the technical reference guide for all available protein assaysLearn more at thermofisher.com/proteinassays40'