Segmented poly(esterurethane urea)s from novel urea-diol chain extenders: synthesis, characterization and in vitro biological properties.

This work describes the preparation, physicochemical characterization, mechanical properties and in vitro biological properties of two bioresorbable aliphatic segmented poly(esterurethane urea)s (SPEUU) based on poly(epsilon-caprolactone) diol (PCL diol), 1,6-hexamethylene diisocyanate and two novel urea-diol chain extenders. To strengthen the interactions through hydrogen bonding in the hard segments of SPEUU, novel chain extenders containing urea groups were synthesized and used in the SPEUU formulation. The different chemical structures of the chain extenders modulated the phase separation of soft and hard segments, as demonstrated by the thermal behavior. The hard segment association was enhanced using a diurea-diol chain extender. The biological interactions between the obtained materials and blood were studied by in vitro methods. Research on the protein adsorption, platelet adhesion and thrombus formation is presented. Studies of protein adsorption onto polymeric surfaces showed that SPEUU adsorbed more albumin than fibrinogen. Studies on platelet adhesion and thrombus formation of SPEUU-coated coverslips indicated the antithrombogenic behavior of these surfaces. The synthesized SPEUU revealed no signs of cytotoxicity to Chinese hamster ovary cells, showing satisfactory cytocompatibility.