Surface analysis of titanium based biomaterials

The objective of the present study was the defined preparation and characterization of various oxide layers on titanium, Ti6Al7Nb and Ti6Al4V. Immobilization techniques for collagen and hydroxyapatite Ca-10(PO4)(6)(OH)(2), the main components contacting an implant within the human body, were tested. The oxide layers were created by electrochemical polarization in phosphate buffer solutions. The thickness of the layers depended on the formation potential. We found a thickness/potential relation of approximately 2.2 nm/V. At formation potentials up to 80 V anatase was the only titanium dioxide modification traceable by Raman spectroscopy and XRD. The electrochemically assisted deposition of hydroxyapatite on these surfaces starts with an amorphous product which can be monitored by SEM, IR and Raman spectroscopy. The immobilization of collagen followed by anodic electrochemical polarization results either in partial integration of collagen fibrils into the oxide layer or at least in a strong increase-of the interaction force between TiO2 and the collagen fibrils.