Phospholipid polymer electrodeposited on titanium inhibits platelet adhesion.

Abstract

To develop metallic materials with thromboresistance, a block-type copolymer (PMbA) was immobilized onto a titanium surface with electrodeposition. The polymer was composed of a poly(2-(methacryloyloxy)ethyl phosphorylcholine (MPC)) segment and a poly(2-aminoethylmethacrylate) segment, which was designed to electronically adsorb to the surface oxide layer on the titanium surface. We confirmed that the polymer was synthesized as expected by nuclear magnetic resonance and gel permeation chromatography. In a 0.26 mmol L(-1) PMbA solution adjusted to pH 11, -3.0 V (vs. an Ag/AgCl electrode) was applied to a titanium substrate for 300 s. The immobilization of PMbA on the titanium was confirmed with X-ray photoelectron spectroscopy and an atomic force microscope. The water contact angle and amount of adsorbed protein on the PMbA-modified surface were decreased. Thrombus formation was not observed all over the surface even when the surface was contacted with human blood without an anticoagulant. Therefore, PMbA covered the surface with even density and poly(MPC) segments in PMbA inhibited platelet adsorption. Electrodeposition with PMbA improves the blood compatibility of a titanium substrate in a simple process.