Anticoagulant surface prepared by the heparinization of ionic polyurethanefilm

We present a new method for heparinization on the surface of polyurethane. The segmented polyurethane was first modified with an epoxide monomer and f ollowed by a ring-opening reaction with diethanolamine to introduce suffici ent hydroxyl groups on the surface of cast film. On this film surface, a ca tionic monomer was grafted by using tetravalent Cerium salt as an initiator . Heparin was immobilized in high efficiency on the ionized surface through static interactions in aqueous solution. The structure of ionized and hepa rinized surfaces were characterized by attenuated total reflectance infrare d spectroscopy (ATR-FTIR) and electron spectroscopy for chemical analysis ( ESCA) spectra. The platelet-rich plasma (PRP) contacting test and the plate let-poor plasma (PPP) clotting time measurements showed that the immobilize d heparin retained its strong anticoagulant property. The release of hepari n from film into salt solution was also studied, and it was found that only a small portion of heparin (10-20%) was released over a period as long as 10 h. It is expected that this new method for surface heparinization can be used to prepare antithrombogenic materials with long-term stability. (C) 2 000 John Wiley & Sons, Inc.