In vitro interaction of human fibroblasts and platelets with a shape-memory polyurethane

Physicochemical and mechanical properties, in vitro cytotoxicity, cytocompatibility, and platelet adhesion were investigated on a shape-memory polyether-based polyurethane (MM-5520 SMPu) using the polyether-based Pellethane 2363-80AE (Pell-2363 SPU) as reference. MM-5520 SMPu and Pell-2363 SPU showed similar average molecular weights and different surface properties, with a higher hydrophilicity and roughness for the SMPu. By tensile tests and dynamic mechanical analysis, the peculiar characteristics of the MM-5520 SMPu were evidenced: strong temperature-dependent behavior for SMPu compared with SPU, and a high shape recovery. MM-5520 SMPu did not show any cytotoxic effect on the adhesion and proliferation of human skin fibroblasts and gingival fibroblasts, and a good cytocompatibility was observed with both cell types, as demonstrated by cell counting and scanning electron microscopy observations. SMPu compared with SPU showed higher adsorption of extracellular matrix proteins such as fibronectin, fibrinogen, and collagens. Proteins adsorbed onto SMPu significantly enhanced the adhesion and proliferation of human fibroblasts. The interaction of SMPu with platelets was studied with platelet rich plasma. Fewer platelets adhered to the SMPu, with minor morphological variations than onto the SPU. The cytocompatibility and hemocompatibility of MM-5520 SMPu combined with its unique properties such as change in shape or in stiffness, depending on practical requirements, make this shape-memory material potentially advantageous for biomedical applications.