Enhanced hemocompatibility and antibacterial activity on titania nanotubes with tanfloc/heparin polyelectrolyte multilayers

Biomaterial-associated thrombus formation and bacterial infection remain major challenges for blood-contacting devices. For decades, titanium-based implants have been largely used for different medical applications. However, titanium can neither suppress blood coagulation, nor prevent bacterial infections. To address these challenges, tanfloc/heparin polyelectrolyte multilayers on titania nanotubes array surfaces (NT) were developed. The surfaces were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and water contact angle measurements. To evaluate the hemocompatibility of the surfaces, fibrinogen adsorption, Factor XII activation, and platelet adhesion and activation were analyzed. The antibacterial activity was investigated against Gram-negative P. aeruginosa and Gram-positive S. aureus. Bacterial adhesion and morphology, as well as biofilm formation, were analyzed using fluorescence microscopy and SEM. The anti-thrombogenic properties of the surfaces were demonstrated by significant decreases in fibrinogen adsorption, Factor XII activation, and platelet adhesion and activation. Modifying NT with tanfloc/heparin also reduces the adhesion and proliferation of P. aeruginosa and S. aureus bacteria after 24 hr of incubation, with no biofilm formation. The modified NT surfaces with tanfloc/heparin polyelectrolyte multilayers are a promising biomaterial for use on implant surfaces because of their enhanced blood biocompatibility and antibacterial properties.