Preparation And Characterization Of Biocompatibility Membrane

In this paper, methyl methacrylate (MMA) and 2-hydroxyethyl acrylate (HEA) copolymer was firstly synthesized by solution polymerization. The copolymer membranes were prepared by a solvent evaporation method and were characterized by differential scanning calorimetry (DSC) and scanning electron microscope (SEM). The influence of the feed mass ratio on the mechanical properties of copolymer membranes was determined. The hydrophilic properties and wettability of copolymer membranes were investigated by dynamic contact angle (DCA) measurement. The adsorption of bovine serum albumin (BSA) onto the surface of copolymer membranes was also studied. It was found that when HEA mass content was between 18% to 25%, the tensile properties of copolymer membranes were up to the membranes of medicine grade polyethylene. The contact angle measurement demonstrated that the hydrophilic increased with HEA mass content which was able to improve the biocompatibility of membranes. The adsorbed amount of BSA decreased with HEA mass content, which was able to improve the anticoagulant of membranes.Then the copolymers of methyl methacrylate (MMA) with 2-methacryloyloxyethyl phosphorylcholine (MPC) were synthesized with the same polymerization method. The copolymer membranes were prepared by a solvent evaporation method and were characterized by DSC, gel permeation chromatography (GPC), nuclear magnetic resonance (1H-NMR), element analysis (EA), and SEM. The equilibrium water content (EWC) and adsorption of BSA onto the surface of copolymer membranes were studied, while DCA was used to monitor hydrophilicity of surface for the copolymer membranes. It was found that EWC of copolymer membranes increased with MPC mass content and the temperature. The results of DCA showed that the surface of membranes could be mobile and be able to rearrange depending on the environment in which the membranes were placed. The adsorbed amount of BSA decreased with the increasing of MPC mass content in the copolymer membranes, which was able to improve the anticoagulant of membranes. The blood anticoagulation of membranes was determined by clotting time measurement and platelet adhesion experiment. It was shown that the copolymer membranes, in which the mass content of MPC was more than 25%, appeared to be beneficial in improving the anticoagulation which was proved to prolong the clotting time and suppress the platelet adhesion.Finally the relationship between the water structure of hydrated MMA/MPC copolymer membranes and the platelet compatibility was illustrated through studying the influence of the monomer mass composition of membranes. The amount of free water increased with increasing mass content of MPC in copolymer membranes from 25～32% which showed the good platelet compatibility.