Grafting sulfobetaine monomer onto the segmented poly(ether-urethane) surface to improve hemocompatibility

Polyurethanes are widely used as blood-contacting biomaterials, due to their good biocompatibility and mechanical properties. Nevertheless, their blood compatibility is still not adequate for more demanding applications. Surface modification is an effective way to improve the hemocompatibility for biomaterials. The purpose of the present study was to synthesize a novel nonthrombogenic biomaterial by modifying the surface of polyurethane. Ozonization was used to introduce active peroxide groups onto the segmented poly(ether-urethane) (SPEU) film surface and graft polymerization of N,N'-dimethyl (methacryloyloxyethyl) ammonium propanesulfonate (DMAPS), a sulfobetaine structure, onto the ozone-activated SPEU surface was conducted. The SPEU-g-PDMAPS film was characterized by ATR-FTIR, XPS, and contact angle measurements. ATR-FTIR and XPS confirmed the graft polymerization. The grafted film possessed a relatively hydrophilic surface, as revealed by contact angle measurement. The blood compatibility of the grafted films was evaluated by a platelet-rich plasma (PRP) adhesion study and scanning electron microscopy, using SPEU film as the reference. No platelet adhesion was observed for the grafted films incubated with PRP at 37 degrees C for 60 and 180 min. This new sulfobetaine structure grafted biomaterial might have potential for biomedical applications.