Synthesis and antithrombogenicity of anionic polyurethanes and heparin-bound polyurethanes.

Two kinds of novel antithrombogenic polyurethane materials were synthesized. One of them is a polyetherurethane with anionic charges on the film surface, and the other is a polyetherurethaneurea to which heparin was covalently bound. The mechanism of their antithrombogenicity was investigated. The anionic polyetherurethane selectively adsorbed albumin, did not cause a conformational change of plasma proteins adsorbed, and suppressed the adherence and deformation of platelets but did not deactivate the blood-clotting system, thus leading to a moderate antithrombogenicity. The heparin-bound polyetherurethaneurea was not favorable for the selective adsorption of albumin, caused the denaturation of plasma proteins adsorbed, and induced the adherence and deformation of platelets but deactivated the blood-clotting system, leading to excellent antithrombogenicity. For the investigation of blood-material interaction, the importance of a multiparameter estimation of the activation of platelets and the blood-clotting system was indicated.