Hi there,

I've always used 1% NP40 in my coIP experiments made from yeast lysates.

Thanks. Dominique. I guess I will try NP-40 then.

RIPA-buffer is 150 mM NaCl, 20 mM Tris-HCl pH 7.5, 1 mM EDTA, 5 mM NaF, 1% NP-40, 0.5% deoxycholate, 0.1% SDS. Of those, the detergents SDS, deoxycholate and NP-40 reduce the yield of precipitate, but also prevent unspecific precipitation of proteins. The higher their concentration, the cleaner the result, but the less intense is the desired band. Therefore, their concentration needs to be titrated for optimal results.

CHAPS Immunoprecipitation Buffer (0.5% CHAPS) will maintain intermolecular interactions following transmembrane and cytosolic protein extraction. The CHAPS reagent is ideal for “pull down - coimmunoprecipitation” (i.e. Co-IP) analysis, since it maintains protein conformation as well as the assembly of protein complexes.

Thanks Jay for your useful answer

Highlights: CHAPS Buffer 

• Strong cell lysis and protein extraction capacity while preserving protein conformation and protein-protein interaction for co-immunoprecipitation (Co-IP) analysis.
• Contains a non-amine buffer (HEPES) enabling cross-linking with NHS-ester derivatives. Ingredients:  0.5% CHAPS, HEPES, NaCl

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