Enhancing Biocompatibility and Antibacterial Activity of Ti6Al4V by Entrapping Ag and Hydroxyapatite Inside Alginate Filled Pores of TiO₂ Layer Grown by Spark Anodizing

A three-step electrochemical process is developed to grow a coating on Ti6Al4V alloy for biomedical applications aimed to enhance its bioactivity. The coating is composed by a porous titanium oxide filled with Ag, alginic acid, and hydroxyapatite to provide antibacterial properties and, at the same time, osteointegration capability. Anodized and treated with the electrochemical process samples are characterized by Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX), X-Ray Diffraction, and Raman Spectroscopy to have information about morphology and composition soon after the fabrication and after immersion in Hanks' solution. Bioactivity of the samples is also proved by electrochemical tests through Electrochemical Impedance Spectroscopy (EIS) measurements. Antibacterial properties, cytocompatibility and hemocompatibility of the samples are successfully demonstrated by in vitro tests.