The endothelialization and hemocompatibility of the functional multilayer on titanium surface constructed with type IV collagen and heparin.

The type IV collagen/heparin (IVCol/Hep) multilayer was developed on amino-silanized titanium (Ti) surface layer by layer self-assembly. Ti, TiOH, TiOHA and TiOHA(HC)3H were characterized by Fourier transform infrared spectroscopy (FTIR), water contact angle measurements and scanning electron microscopy (SEM), respectively. Alcian Blue 8GX staining and immunofluorescence staining were used to characterize the heparin (Hep) and type IV collagen (IVCol), respectively. The blood compatibilities of Ti and the treated Ti were evaluated by platelet adhesion test and clotting time using PRP. Blood compatibility tests reveal that the assembled functional multilayer displayed less platelets adhesion and prolonged APTTs time compared with the controlled Ti. Endothelial cells (ECs) culture results showed more attached and proliferated ECs on the TiOHA(HC)3H than that on Ti, especially compared with that on TiOH and TiOHA. Thus, the assembled Hep and IVCol multilayer can improve the cell compatibility and the blood compatibility. We anticipate that this IVCol/Hep functional multilayer will be beneficial to enhance the biocompatibility of the Ti-based biomaterial devices.