Cardiovascular disease has become a great threat to the health of mankind; current titanium (Ti) stents fail due to late stent thrombosis caused by the lack of re-endothelialization of the Ti stent. The objective of this study was to design a novel cardiovascular Ti implant with improved surface biocompatibility. TiO2 nanotubes with a diameter of 110 nm were anodized at a constant voltage of 30 V, and fibronectin was immobilized onto the TiO2 nanotubes using polydopamine. The element composition, morphology, and wettability of the different substrate surfaces were characterized by x-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and contact angle measurements, respectively, confirming the successful immobilization of fibronectin. In vitro experiments including immunofluorescence staining, Cell Counting Kit-8 (CCK-8), and nitric oxide (NO) and prostacyclin (PGI2) release demonstrate that fibronectin modified TiO2 nanotubes supported cell adhesion, proliferation, and normal cellular functions of human umbilical vein endothelial cells (HUVECs). These methodologies can be applied for future fabrication of cardiovascular stents.
Keywords: Fibronectin; TiO2 nanotubes; biofunctionalized titanium; human umbilical vein endothelial cells; polydopamine.