A dynamic dialysis method for studying protein-ligand binding using chromatographic theory

A new dynamic dialysis method has been developed for studying protein-ligand binding phenomena. The method depends on analysis of the elution pattern of ligand in a single dialyzing process where the ligand concentration in the sample compartment changes greatly with time. The dialyzer is composed of a long, narrow chamber (the sample compartment) between two sheets of semipermeable membrane and two outside chambers (the sink compartment) connected as a single path. Eluting buffer flows in the sink compartment to exchange the ligand with the solution in the sample compartment. Therefore, the ligand concentration gradient in the sink compartment is in the longitudinal direction. The mathematical expressions to analyze the experimental data were derived from a modified theory of chromatography. Examination of the binding of sulfanilamide to bovine serum albumin using this method shows that these equations are valid for use in studying protein-ligand binding.