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Abstract: Films of Ti–Ca–P–C–O–(N), Ti–Ca–C–O–(N) and Ti–Zr–C–O–(N) were deposited by DC magnetron sputtering or ion implantation-assisted magnetron sputtering of composite targets TiC0.5+10%Ca10(PO4)6(OH)2, TiC0.5+20%(CaO+TiO2) and TiC0.5+10%ZrO2 in an Ar atmosphere or reactively in a gaseous mixture of Ar+14%N2. The microstructure, elemental and phase composition of films were studied by means of X-ray diffraction, transmission electron microscopy, scanning force microscopy, X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy. The films were characterized in terms of their hardness, Young''s modulus, elastic recovery, adhesion strength, and friction and wear both in air and under physiological solution. Particular attention was paid to the analysis of deformation and fracture for various film/substrate systems during scratch testing. The biocompatibility of the films was evaluated by both in vitro and in vivo experiments. In vitro studies involved the investigation of adhesion, spreading, and proliferation of MC3T3-E1 osteoblasts and IAR-2 epithelial cells, morphometric analysis, actin cytoskeleton, focal contacts staining, alkaline phosphatase activity and von Kossa staining of osteoblastic culture. Cell culture experiments demonstrated an increase of osteoblastic proliferation on Ca- and P-incorporated films. In vivo studies were fulfilled by subcutaneous implantation of Teflon plates coated with the tested films in mice and analysis of the population of adherent cells on their surfaces. The results obtained show that multicomponent nanostructured Ti–(Ca, Zr)–(C, N, O, P) films possess a combination of high hardness, wear resistance and adhesion strength, reduced Young''s modulus, low friction coefficient and high biocompatibility. [Copyright &y& Elsevier]

Abstract: A comparative investigation of multicomponent thin films based on the systems Ti–Ca–C–O–(N), Ti–Zr–C–O–(N), Ti–Si–Zr–O–(N) and Ti–Nb–C–(N) is presented. TiC0.5+10%CaO, TiC0.5+20%CaO, TiC0.5+10%ZrO2, TiC0.5+20%ZrO2, Ti5Si3+10%ZrO2, TiC0.5+10%Nb2C and TiC0.5+30%Nb2C composite targets were manufactured by means of self-propagating high-temperature synthesis, followed by DC magnetron sputtering in an atmosphere of argon or in a gaseous mixture of argon and nitrogen. The films were characterized in terms of their structure, chemical composition, surface topography, hardness, elastic modulus, elastic recovery, surface charge, friction coefficient, and wear rate. The biocompatibility of the films was evaluated by both in vitro and in vivo experiments. In vitro studies involved the investigation of the proliferation of Rat-1 fibroblasts and IAR-2 epithelial cells on the tested films, morphometric analysis and actin cytoskeleton staining of the cells cultivated on the films. In vivo studies were fulfilled by subcutaneous implantation of Teflon plates coated with the tested films in mice and analysis of the population of cells on the surfaces. The films deposited under optimal conditions showed high hardness in the range of 30–37GPa, significant reduced Young''s modulus, low friction coefficient down to 0.1–0.2 and low wear rate in comparison with conventional magnetron-sputtered TiC and TiN films. The surface of all films was negatively charged with an outstanding shift between the Ar and Ar+N2 Zeta potential curves that reaches 5mV at the highest pH values. We did not detect statistically significant differences in the attachment, spreading and cell shape of cultured IAR-2 and Rat-1 cells on the Ti–Ca–C–O–(N), Ti–Zr–C–O–(N) (TiC0.5+10%ZrO2 target), Ti–Si–Zr–O–(N) films and the uncoated substrata. The adhesion and proliferation of cultured cells in vitro was perfect at all investigated films. Assessment of the population of cells covering on the Teflon plates coated with the Ti–Ca–C–O–(N) and Ti–Zr–C–O–(N) films after 16 weeks of subcutaneous implantation revealed the high biocompatibility level of tested films and absence of inflammatory reactions in mice. Contrary, the epitheliocytes and fibroblasts cultivated on the Ti–Zr–C–O–(N) (TiC0.5+20%ZrO2 target) and Ti–Nb–C–(N) films had disturbing actin cytoskeleton. [Copyright &y& Elsevier]