MEASUREMENT OF THE BINDING OF PROTEINS TO POLYELECTROLYTES BY FRONTALANALYSIS CONTINUOUS CAPILLARY ELECTROPHORESIS

We have developed a novel technique, frontal analysis continuous capil lary electrophoresis (FACCE), to study the binding of proteins to poly electrolytes. Compared with existing electrophoresis methods such as c onventional frontal analysis and the Hummel-Dreyer method, FACCE offer s enhanced lower detection limits and is free from effects due to slow binding kinetics, thus making it suitable for studying equilibrium sy stems, In addition, with a single calibration, FACCE provides for effi cient quantitative analysis. Here we report results obtained with beta -lactoglobulin as the ligand and sodium poly(styrenesulfonate) (NaPSS) as the ligand-binding substrate. For this model system, FACCE yields reproducible calibration curves and binding isotherms. The binding par ameters so determined are compared with previous results for other pro tein-polyelectrolyte systems.