INVESTIGATION OF THE ELECTROCHEMICAL BEHAVIOUR AND SURFACE CHEMISTRY OF A Ti-13Nb-13Zr ALLOY EXPOSED IN MEM CELL CULTURE MEDIA WITH AND WITHOUT THE ADDITION OF H2O2

Promoting and understanding the formation of hydroxyapatite on biocompatible metals in the body is a very important topic of biomaterials research. In this paper, the formation of hydroxyapatite on a near-β Ti-13Nb-13Zr alloy by immersion in minimal essential medium (MEM) with and without the addition of H2O2 has been studied using electrochemical methods, SEM and XPS. The Ti-13Nb-13Zr alloy exhibits passive behaviour over a wide potential range when immersed in MEM and the passive film is composed of an inner barrier layer and an outer porous layer. Exposure for 72 hours in the MEM solution results in the formation of a surface layer comprised of an island-like distribution of HA material and adsorbed amino acids. The addition of H2O2 to the MEM solution strongly promotes the formation of a thicker, continuous nanocomposite layer of HA and amino acids. For Ti alloys, the release of H2O2 in the anti-inflammatory response appears to be an important beneficial process as it serves to accelerate osseointegration.