Antibacterial Nanostructured Ti Coatings by Magnetron Sputtering: from Laboratory Scales to Industrial Reactors

Abstract

Based on an already tested laboratory procedure, a new magnetron sputtering methodology to simultaneously coat two-sides of large area implants (up to ~15 cm2) with Ti nanocolumns in industrial reactors has been developed. By analyzing the required growth conditions in a laboratory setup, a new geometry and methodology have been proposed and tested in a semi-industrial scale reactor. A bone plate (Depuy Synthes) and a pseudo-rectangular bone plate extracted from a patient have been coated following the new methodology, obtaining that their osteoblast proliferation efficiency and antibacterial functionality were equivalent to the coatings grown in the laboratory reactor on small areas. In particular, two kinds of experiments have been performed: analysis of bacterial adhesion and biofilm formation, and osteoblasts-bacteria competitive in vitro growth scenarios. In all these cases, the coatings show an opposite behavior towards osteoblast and bacterial proliferation, demonstrating that the proposed methodology represents a valid approach for industrial production and practical application of nanostructured titanium coatings.