Reduced platelets and bacteria adhesion on poly(ether ether ketone) by photoinduced and self-initiated graft polymerization of 2-methacryloyloxyethyl phosphorylcholine.

Aromatic poly(ether ether ketone) (PEEK) is a super engineering plastic, which has good mechanical properties and is resistant to physical and chemical stimuli. We have, therefore, attempted to use PEEK in cardiovascular devices. Synthetic cardiovascular devices require both high hemocompatibility and anti-inflammatory activity in addition to the mechanical properties. We modified the PEEK surface by photoinduced and self-initiated graft polymerization with 2-methacryloyloxyethyl phosphorylcholine (MPC; PMPC-grafted PEEK) for obtaining good antithrombogenicity. Polymerization was carried out on the surface of PEEK under radiation of ultraviolet (UV) light during which we controlled monomer concentrations, temperatures, and UV intensities. The biological performance of the PMPC-grafted PEEK was examined and compared with that of unmodified PEEK. With increase in the thickness of the PMPC layer, the amount of fibrinogen adsorption decreased significantly in comparison to that in the case of unmodified PEEK. When placed in contact with human platelet-rich plasma, surface of the PMPC-grafted PEEK clearly showed inhibition of platelet adhesion and activation. Also, bacterial adhesion was reduced dramatically on the PMPC-grafted PEEK. Thus, the PMPC grafting on PEEK improved the antithrombogenicity.