Exploitation of specific cell membrane receptor molecules is a promising avenue for the separation and purification of particular cell populations for biomedical and biotechnological purposes. Cell affinity chromatography is a technique which uses this principle to separate cells. In it, ligand molecules with a high binding affinity for specific receptors on targeted cell populations are immobilized on surfaces over which mixed cell populations are passed. These targeted populations are preferential retained, affecting a separation.
Often, the resulting separation is not as selective or efficient as the receptor/ligand biochemistry would promise. We present a theoretical analysis which elucidates the role of physical factors, such as van der Waals, electrostatic, and fluid mechanical forces, in affecting cell adhesiveness and hence selectivity. We demonstrate that only fairly narrow ranges of parameters characterizing these forces permit the selectivity inherent in the receptor/ligand biochemistry.