A method for cooperative or noncooperative binding studies using nonlinear regression analysis on a microcomputer.

Ligand-macromolecule interactions are studied by nonlinear regression analysis performed using a microcomputer (SYMAG-Micromachine 3000/Z). The basic phenomenon is described by the Clark equation B = (Formula: see text), where B and F represent bound and free ligand, respectively, Ni the total concentration of binding sites, and Ki their corresponding affinity constant. The programs of calculation have been extended also for Hill and for Adair equations using the Gauss algorithm described by E. E. Beaulieu and J. P. Raynaud [Eur. J. Biochem. 13, 293 (1970)]. A statistical test of F type is introduced to test the quality of the fit and compare the representations of the phenomenon using the different equations.