PROTEIN PERMEATION THROUGH POLY(VINYL ALCOHOL) HYDROGEL MEMBRANES

Hydrogel membranes were prepared by radiation and chemical cross-linki ng of poly(vinyl alcohol) (PVA) in aqueous solutions. Effects of PVA c oncentration, PVA molecular weight and radiation dose, as well as conc entration of cross-linking agent, in the case of the chemical cross-li nking procedure, on the permeation of insulin, albumin and immunoglobu lin (IgG) through the membranes were investigated. Glucose permeation was also studied. The cross-linking density affected the size of the m acromolecular mesh of the hydrogel network and thus the water content of the membrane responsible for the diffusion of the solutes. The diff usion coefficient linearly increased for all the solutes with increasi ng water content in the PVA hydrogels, indicating that diffusion occur s primarily through the water hydrating the polymer network. The perme ability study showed that the water content as well as the mesh size h ad an influence on the diffusion of low molecular weight glucose and i nsulin. Although the diffusion of higher molecular weight solutes, suc h as albumin and IgG, was not so much affected by the mesh size of ela borated PVA hydrogel membranes, the diffusion of these proteins was ve ry low.