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 (HA) on blocompatible metals in the body is a very important topic of biomaterials research. In this paper, the formation of HA on a near-ss 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 h in the MEM solution results in the formation of a surface layer composed 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 osseointeg ration. Copyright (c) 2008 John Wiley & Sons, Ltd.