1973 Volume 46 Issue 9 Pages 2735-2738
The binding isotherms of bovine serum albumin (BSA) with cationic detergents, decyltrimethylammonium bromide, dodecyltrimethylammonium bromide, and tetradecyltrimethylammonium bromide have been determined at temperatures 8 and 25 °C for pH 6.8. The isotherms have also been determined at pH 3.0 and 25 °C. The effect of KBr on the binding of dodecyltrimethylammonium bromide to BSA has been examined at 25 °C for pH 6.8. The results obtained are as follows. (a) The average number of detergent cations bound, \barv, increased with the increase in the length of hydrocarbon chain, (b) the standard free energy changes −ΔG°, calculated from the intrinsic association constants K, were comparable with the cohesive energy change when one methylene group is transferred from the aqueous phase to the hydrocarbon environment on micellization, (c) values of \barv at pH 3.0 differ only slightly from those at pH 6.8 in a wider range of detergent concentration, and (d) the presence of the salt shifted the binding isotherms to the lower detergent concentrations. These results are discussed as regards the nature of micellization of detergents.
This article cannot obtain the latest cited-by information.