Antithrombogenic Surface Constructed by Block-type Phospholipid Polymer and Segmented Polyurethane

抄録

Segmented polyurethanes (SPUs) are widely used in biomedical field such as cardiovascular catheters, diaphragms of artificial hearts because they have flexible but tough mechanical properties. However, their antithrombogenicity under blood contacting conditions are not sufficient to prevent clot formation for long term. For preparing small-diameter vascular grafts, it is necessary to obtain both antithrombogenic and biocompatible surface. In this study, poly(2-methacryloyloxyethyl phosphorylcholine-block-2-ethylhexyl methacrylate) (B-PMEH), which has an affinity with SPU on a molecular level was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization method. The B-PMEH was blended for preparing a SPU/B-PMEH polymer alloy membrane (SB film). This film drastically lowered the amount of absorbed fibrinogen and platelet adhesion compared to that on SPU without any adverse effect on the mechanical property of the SPU when B-PMEH was highly concentrated at the surface of the SB film. This means that the poly(MPC) segments in the B-PMEH improved the antithrombogenicity of the SPU. We succeeded in preparing a novel polymer alloy that possesses both the good mechanical property and the improved antithrombogenicity.