Biological Properties of Ti-Si-C-O-N Thin Films

The main aim of this work was to study the feasibility of new coatings for medical devices. Ti-Si-C-O-N films were deposited by DC unbalanced reactive magnetron sputtering, using different oxygen and nitrogen partial pressure ratios (pO2/pN2). Surface properties were also analysed. Staphylococcus epidermidis was used to study biofilm formation and cytotoxicity was determined using fibroblasts. Surface morphology changed with the increase of pO2/pN2. Samples of high hydrophobicity displayed opposite behaviour in terms of biofilm formation, presenting the highest and lowest biomass. Moreover, the sample with the highest Ti content was the one, with the lowest biofilm amount, raising the possibility of a correlation between Ti and biofilm formation capability. In fact, this sample also displayed the highest degree of cytotoxicity (near 35%). This work shows the feasibility of the proposed coatings and highlights the importance of joining together both biological properties (biofilm formation and cytotoxicity) with the surface characterization.