Evolution of commercially pure titanium/heparin/poly (ethylene glycol) substrate with improved biocompatibility for cardiovascular device applications

The present work focuses on the evolution of alkali-modified commercially pure titanium (cpTi)-heparin-polyethylene glycol (PEG; 20,000 MW) substrate via a layer-by-layer physical adsorption process. Physicochemical and in-vitro biological properties of developed samples were studied analytically before and after heat treatment. A nanoporous network after alkali treatment and a homogenous polymer layer over the alkali-treated cpTi-heparin surface was revealed by physicochemical characterization. Heparin stability was monitored and showed good stability with PEG coating in PBS (pH=7.4) for 24 h. The thrombin activity was found to be reduced with a PEG-coated heparin-loaded cpTi surface. The nanoporous structure holding −OH groups showed better biocompatibility. The modified cpTi surfaces exhibited good antibacterial performance against Staphylococcus aureus. Heparin toxicity has been estimated to determine the effect of heparin concentration in interstitial cell lines. All the lower concentrations of heparin showed good cell viability. Therefore, the modified cpTi substrates are promising candidates for cardiovascular device applications.