Optimization of an obtaining nanotubes process

Abstract

Because of the aging of the population and the increase medical interventions with prothesis, the use of metallic implants is increasing exponentially rising the need to improve their lifespan and biocompatibility. So that, it is important to improve how the material interact with the tissues of the body. That is the reason why, this project has aimed at making surface modifications of titanium implants to increase their bioactivity. Specifically, this study has been focused on making surface modifications using an electrochemical anodization process of a particular titanium alloy, Ti-6Al-7Nb, to generate nanotubes. Through the electrochemical anodization process, a titanium dioxide (TiO2) layer is generated. This oxide layer provides the surface with a high corrosion resistance that protects and prevents the release of ions from the implant to the body. Also, this TiO2 layer is a bioactive ceramic material which will favor cell adhesion and proliferation. Therefore, this project has consisted of three steps: optimize the conditions to create nanotubes on an industrial level, characterize the coatings made through imaging with different microscopic techniques and finally validate the sample bioactivity by cellular viability tests. Last but not least, it is important to note the methodology behind this degree thesis. First the background of titanium and its alloys as a biomaterial is explained, as well as the evolution of implants and current techniques available to improve the bioactivity of surfaces. In addition, a market study has been carried out and both the technical and economic feasibility of the project have been studied. Finally, the current regulations on medical devices have been considered. To sum up, it has been possible to establish an overview of the aspects necessary to carry out modifications of surfaces of medical implants.