Surface modification of poly(propylene carbonate) by layer-by-layer assembly and its hemocompatibility

Abstract

Polyelectrolyte multilayers of negative charged heparin (Hep) and positive charged lysozyme (LYZ) were used to immobilize on the poly(propylene carbonate) (PPC) surface by layer-by-layer (LbL) assembly to improve hemocompatibility. X-ray photoelectron spectroscopy confirmed that the surface was successfully modified. The process of LbL and the subsequent fibrinogen adsorption were monitored using a quartz crystal microbalance with dissipation in real time. The adsorbed fibrinogen on the PPC surface formed dense side-on structures, which led to lots of platelet adhesion. However, on the surface of PPC-g-(LYZ-co-Hep)₃, fibrinogen molecules formed a relatively loose adsorbed layer, which had an excellent fibrinogen resistance due to release of dissipated energy. Combined with the results of platelet adhesion, erythrocyte adhesion, and hemolysis, we concluded that the PPC-g-(LYZ-co-Hep)₃ surface had high performance with hemocompatibility due to highly hydrophilicity of LYZ and anticoagulation of Hep, which can be as a candidate scaffold material for blood vessel tissue engineering.