A general model is presented and used to predict the dynamic behavior of the adsorption and wash stages of biospecific adsorption (affinity chromatography) in a finite bath. The model accounts for film and diffusional mass transfer resistances as well as for the rates of interaction between adsorbates and ligands. The model is applicable to single and multicomponent biospecific as well as nonspecific adsorption, and the adsorbates may be monovalent or multivalent. The predictions of the model are compared with the experimental data of the adsorption of β-galactosidase onto immobilized anti-β-galactosidase.
The results of biospecific adsorption of bivalent adsorbates indicate that a competition for ligands occurs between molecules forming one-site interaction and two-site interaction complexes. This competition can lead to the displacement of the adsorbate from the adsorbate-ligand complex whose formation is least favored.