SURFACE MODIFICATION OF POLYMERIC BIOMATERIALS BY ALBUMIN GRAFTING USING GAMMA-IRRADIATION

Polymeric biomaterial surfaces were modified by albumin grafting to im prove their blood compatibility. Albumin molecules were functionalized by introducing double bonds using glycidyl acrylate. The functionaliz ed albumin was covalently attached to various biomaterial surfaces suc h as polypropylene, polycarbonate, and poly(vinyl chloride) by gamma-i rradiation. Surface-induced platelet adhesion and thrombus formation o n the albumin-grafted surfaces was examined using computer-enhanced vi deo microscopy and scanning electron microscopy. The amount of the gra fted albumin was dependent on the gamma-irradiation dose and the conce ntration of albumin used for adsorption. The grafted albumin molecules remained on the surface even after exposure to blood for prolonged ti me periods. This approach was used to graft albumin to polymeric mater ials of an oxygenator. The albumin grafting resulted in a substantial improvement in blood compatibility as compared to control oxygenators. The covalent grafting of functionalized albumin by gamma-irradiation obviates the need for premodification of chemically inert polymer surf aces. It is useful for albumin grafting to various biomaterial surface s. (C) 1994 John Wiley & Sons, Inc.