Biocompatibility Assessment of Coatings Obtained in Argon and Nitrogen Atmospheres for TiNi Materials

Abstract

This work aims to study the cytocompatibility of protective coatings obtained in argon and nitrogen atmospheres on a TiNi surface. Particular attention is paid to comparing the interaction of cell culture with coatings and an uncoated TiNi sample, using for comparison the number of viable cells on the surface, the phase composition, structure, wettability, surface charge and topography. The Ti/Ni/Ti nanolaminate was deposited on a TiNi substrate by magnetron sputtering. Reaction annealing of Ti/Ni/Ti nanolaminate on a TiNi substrate, when heated to 900 °C in argon, leads to the formation of a dense two-layer coating 2.0–2.1 μm thick: layer I (TiO + Ti2N), layer II (Ti4Ni2 O(N)). Reaction annealing in nitrogen leads to the formation of a thin three-layer nanocoating 250 nm thick: I (TiO2 + TiN), II (Ti4Ni2N(O) + Ti3Ni4), III (TiN). The coating synthesized in nitrogen is more favorable for cell attachment and proliferation because of the moderately hydrophilic rough surface and mixed phase composition of titanium nitrides and oxides.

Mechanical Properties, Biocompatibility and Antibacterial Behaviors of TaO0.2N0.8 and TaO0.2N0.8-Ag Nanocomposite Thin Coatings

“…Theoretically, even with a little change on the ratio of oxygen in the nitride structure, the oxynitride's chemical and physical properties will definitely change too. Normally, nitrogen is less electronegative, the bonds between metal and nitrogen atoms are definitely more covalent than the bonds between and oxygen atoms [14][15][16]. Without any doubt, the variation of O/N ratio in oxynitride materials would cause the change of some characteristic properties.…”