Construction of heparinylated multilayer films on TiO via streptavidin/biotin interaction

Construction of heparinylated multilayer films on TiO via streptavidin/biotin interaction was conducted in the present study. An organic layer of 3-aminopropylphosphonic acid (APP) was first introduced on TiO by self-assembling, and then biotin was immobilized by photochemical methods. So streptavidin and biotinylated heparin were assembling through biorecognition, and a desired 6-layer heparinylated multilayer was obtained through layer-by-layer driven by streptavidin/biotin interaction. The in vitro platelet adhesion and activation were investigated by a static platelet adhesion test. The clotting time was examined by activated partial thromboplastin time (APTT). Results show that the heparinylated multilayer coated TiO can significantly decrease platelet adhesion and activation, and prolong clotting time of APTT compared to untreated TiO, which indicates the heparinylated multilayer coated TiO displays more excellent anticoagulation performance than that of the bare TiO.

. Schematic figures of layer-by-layer assembling of streptavidin and biotinylated heparin.Highlights► Heparinylated multilayer films was constructed on TiO. ► A desired heparinylated multilayer can be obtained through layer-by-layer driven by streptavidin/biotin interaction. ► The heparinylated multilayer coated TiO has improved anticoagulation properties.