An in vitro Study of Heparin-Immobilized Poly(ethylene-graft-vinylacetate) and Poly(ethylene-graft-vinylpyridine)

摘要

Polyethylene (PE) was modified by radiation-induced grafting of vinyl acetate (VAc) and vinyl pyridine (VP), followed by heparinization of the surface. The unmodified, the grafted, and the heparin-immobilized samples were studied with X-ray photoelectron spectroscopy. The heparinized samples were also studied by Laser Scanning Confocal Microscopy and by the toluidine blue method. The biological activity of heparin against thrombin formation was evaluated by the chromogenic method. The graft-copolymerization of PE with VAc or VP, as well as the heparin immobilization were successfully carried out. The heparin was strongly attached to the VP-grafter PE, but underwent slow release when immobilized on the hydrolyzed VAc-grafter PE. The grafted and heparinized materials showed no toxicity when examined by in vitro cell studies, and the immobilized heparin retained its biological activity.