A new method has been developed for determining macroscopic binding constants of a few surfactants to some macromolecules. Then, the binding of ionic surfactants (cetyltrimethyl ammonium bromide, tetradecyltrimethyl ammonium bromide, and sodium tetradecyl sulfate) [STS]) to macromolecules (bovine serum albumin, human serum albumin, and polyvinyl pyrollidone was investigated. The binding constants and binding isotherms were calculated using this new method. Experimental data were obtained through a potentiometry technique. Finally, the results obtained were compared with the results obtained based on the Wyman binding potential concept.