Isotachophoretic electrodesorption of proteins from an affinity adsorbent on a microscale

Cationic isotachophoresis was used for the desorption of mouse monoclonal antibody to transferrin strongly affinity-bonded to transferrin immobilized on polyethyleneglycol terephthalate powder. The electrodesorption under nondestructive conditions was effected in the capillary isotachophoresis apparatus of our own construction which was equipped with an adsorption element. The electrodesorption is on-line connected with quantitative isotachophoretic analysis of the antibody desorbed. Only a few tens of microliters of the affinity adsorbent and several nanomoles of the antibody are needed for the characterization of the capacity of the affinity adsorbent and the conditions of adsorption and desorption.