Study of TaN and Ta2O5 coatings obtained by sputtering with non-self-sustained gas discharge for biomedical implant modification

Tantalum nitride (TaN) and tantalum oxide (Ta2O5) coatings were manufactured by using sputtering with sustained gas discharge in Bulat-type facility. Characteristics of the obtained coatings, including surface morphology, nanohardness, surface wettability, Young's modulus, and biocompatibility, were investigated. Different surface roughness of TaN and Ta2O5 made the main contribution to the transition to hydrophobic surface properties, which led to different conditions for cell adhesion. According to the test results, the average value of the elastic modulus for the sample coated with TaN was 426.1 GPa and Ta2O5 - 172.4 GPa, respectively. The maximum nanohardness was obtained for the TaN nitride coating and reached 37.8 GPa. The biocompatibility of the samples was assessed in vitro by the susceptibility of the surface of the material to cells, since cell attachment and proliferation are closely related to the surface characteristics of the implant. The Ta2O5 coating has shown appropriate biocompatibility profile, as it provides an ideal environment for Mesenchimal Stem Cells (MSC) adhesion from day 1, followed by cell proliferation until the end of the experiment. The TaN coating did not support cell attachment and proliferation during the experiment. •TaN and Ta2O5 coatings were fabricated using sputtering with non-self-sustained gas discharge.•Low surface wettability prevents cell adhesion even with pronounced nanostructured topography.•The coefficient of resistance to plastic deformation TaN coating is 6 times higher than for Ta2O5.•Cell culture experiment demonstrates high biocompatibility of Ta2O5 coating.