SORPTION KINETICS AND BREAKTHROUGH CURVES FOR PEPSIN AND CHYMOSIN USING PEPSTATIN-A AFFINITY MEMBRANES

Isotherms and kinetic parameters for pepsin and chymosin sorption to immobilized pepstatin A were measured in batch experiments. The measured single-solute parameters were used in an affnity-membrane model which included competitive sorption kinetics, axial diffusion and dead volume mixing. The predictions made using the affinity-membrane model matched the experimental breakthrough curves, whereas predictions made using local-equilibrium theory were a distinct mismatch. The performance of affinity-membrane separations was dominated by slow sorption kinetics.