CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate ) is a zwitterionic detergent used to solubilize proteins. It is used as a non-denaturing solvent in the process of protein purification and is especially useful in purifying membrane proteins, which are often sparingly soluble or insoluble in aqueous solution due to their native hydrophobicity. CHAPS can also be used in conjunction with nonionic detergents such as Triton X-100.