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Regularities of changes in chemical composition and microstructure of titanium nickelide upon high-dose ion-beam implantation of silicon into its surface were studied. It was shown that irradiation of a TiNi alloy with silicon ion beams results in formation of a surface oxide layer about six times thicker than that at the surface of the unirradiated alloy. The surface oxide layer of the ion-beam-modified alloy has an oxygen concentration which is ∼20% greater than that of the unmodified TiNi surface layer and lacks nickel, whose concentration is near zero to a sample depth of about 20 nm. Investigation of the near-surface region beneath the irradiated surface of TiNi samples by electron backscatter diffraction revealed that, under the action of a silicon ion beam, the near-surface region of individual B2-phase grains rising to the surface is fragmented with formation of a grain-subgrain structure with fragment (grain) sizes decreased down to 5 to 15 μm. It was suggested that grain orientation influences the observed effect.

The results of the investigation of the proliferation effect on a mesenchymal stem cell (MSC) culture and the estimates on cytotoxicity of surfaces of titanium nickelide specimens prepared using special mechanical and electrochemical methods and characterized by different morphology and roughness are presented. The specimens of the alloy based on titanium nickelide are shown not to exert any toxic action on the MSCs of rats. When cultivated in the presence of the tested materials or being on their surfaces, MSCs preserved their viability, adhesive and morphological properties, and the ability for in vitro proliferation. This was confirmed by the following methods: cell counting in a Goryaev chamber, MTT, flow cytometry, and light and fluorescent microscopy. It was revealed that the proliferation processes are weakly pronounced on the surface of TH1(B) specimens whose C10–11 class roughness was achieved by multistage mechanical grinding to “high luster” and subsequent electrolytic grinding. On the contrary, the C7 class roughness of the TH1(A) specimen surfaces achieved by chemical etching and subsequent electrolytic grinding is more optimal for MSC proliferation.

A sorption material based on acetylcellulose microfibers, modified by nanostructural aluminum oxyhydroxide, is described, and its microbiological activity is studied. The data on the adsorption efficiency of microorganisms of different morphology and size and bacterial endotoxin (BE) from aqueous media are presented.