PHYSICAL AND BIOLOGICAL PROPERTIES OF COMPOUND MEMBRANES INCORPORATING A COPOLYMER WITH A PHOSPHORYLCHOLINE HEAD GROUP

A copolymer (PMB) having a polar head group 2-methacryloyloxyethyl pho sphorylcholine (MPC) copolymerized with n-butyl methacrylate (BMA) may provide a haemocompatible surface for implantable devices. Pure PMB m embranes and compound membranes composed of PMB coated onto polyuretha ne (PU + PMB) and poly(vinyl chloride) (PVC + PMB) have been prepared. Fundamental studies on these membranes included the analysis of molec ular distribution and orientation, the characterization of surface phy sical properties and the examination of blood-membrane interactions. T he experimental techniques used were Fourier transform infrared spectr oscopy (FTIR), atomic force microscopy (AFM) and scanning electron mic roscopy (SEM). Significant differences between PU + PMB and PVC + PMB membranes were found. Compound PVC + PMB and pure PMB membranes exhibi ted favourable surface properties for haemocompatibility and also show ed low adhesion of blood components, whereas PU + PMB displayed the co ntrary. This leads to the hypothesis that the underlying material has a major influence on the surface properties of compound membranes. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.