Radioimmunoprecipitation assay buffer

Radioimmunoprecipitation assay buffer (RIPA buffer) is a lysis buffer used to lyse cells and tissue, for radio immunoprecipitation assay (RIPA).^[1][2] This buffer is more denaturing than NP-40 or Triton X-100 lysis buffer because it contains the ionic detergents SDS and sodium deoxycholate as active constituents and is particularly useful for disruption of nuclear membranes in the preparation of nuclear extracts. The RIPA buffer gives low background but can denature kinases.

Recipe

RIPA buffer recipe for total protein extract is as follows:

• 25mM Tris (10 mM sodium phosphate may be used instead), pH 7–8
• 150 mM NaCl
• 0.1% SDS (optional)
• 0.5% sodium deoxycholate
• 1% Triton X-100 or NP-40
• Protease inhibitors such as PMSF or cocktail protease inhibitors which are commercially available (use according to the manufacturer's guide)

References