On the Application of Oxynitride Thin Films in Biomedicine

The structure, morphology, and roughness of Ti-O-N coatings applied to stainless steel surfaces using reactive magnetron sputtering are investigated for use as biomedical stents. The deposition modes are analyzed with a negative bias applied to the substrate (-60 V), with no bias applied to the substrate, and with varying nitrogen-to-oxygen ratios in the working gas. The resulting coatings exhibited an anatase structure. Analysis by scanning electron microscopy shows a decrease in the grain size of the films with an increase in nitrogen concentration in the working gas when a negative bias (-60 V) is simultaneously applied. In vitro studies conducted on blood donors, involving blood collection followed by plasma separation from erythrocytes through centrifugation at a rate of 1-2 mL/min, demonstrate that the use of Ti-O-N-coated substrates (-60 V) decrease platelet levels and increase hematocrit values.