PREDICTION OF DENATURING TENDENCY OF ORGANIC-SOLVENTS IN MIXTURES WITH WATER BY MEASUREMENT OF NAPHTHALENE SOLUBILITY

Addition of miscible organic solvents to water increases the solubilit y of naphthalene. The logarithm of the solubility is linearly dependen t on the co-solvent concentration, in an intermediate range. The relat ive solubilising effects of different solvents correlate well with the ir known tendency to denature proteins (using literature data for tryp sin, cytochrome c, chymotrypsinogen, chymotrypsin, laccase and myoglob in). This is expected if denaturation occurs when the hydrophobic effe ct has been reduced by a characteristic extent for a given protein. Na phthalene solubility predicts denaturation as well as does the denatur ation capacity model.