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Transparent oxide semiconducting thin films based on mixed Ti-V oxides were prepared using a modified reactive magnetron sputtering method. Based on structural investigations performed with the help of x-ray diffraction and transmission electron microscopy analysis, two distinct regions in the prepared thin film have been observed: a nanocrystalline TiO-VO-VO mixed composition, and a thin layer consisting of amorphous phase and nanocystalline TiO phase deposited directly at the substrate. Optical measurements show excellent transmission in the visible spectral range of 73%, on average. Resistivity of the thin film was found at the order of 10 Ω cm at room temperature. The preparation of mixed Ti-V oxides provides a combination of high transparency and semiconducting properties. [ABSTRACT FROM AUTHOR]

Background: Biomaterials in the form of thin-film coatings as-deposited on different substrates are nowadays increasingly popular. In particular coatings based on a combination of biocompatible materials (eg. titanium) with metals of high biological activity (eg. copper) have a potentially wide range of applications as active films, intended for various types of medical devices., Objectives: The aim of this study was to present a method for preparation and analysis of the properties of Cu-Ti thin films, in particular their biological activity in connection with the properties of the surface., Material and Methods: The films were prepared by magnetron sputtering method with the aid of an innovative four-target apparatus. During deposition process two metallic targets (copper and titanium) were sputtered under an argon atmosphere. Material composition of produced coatings was characterized by scanning electron microscope equipped with an adapter for energy dispersive spectroscopy. Moreover, the surface microstructure and roughness of coatings was characterized based on three-dimensional surface profiles, which were obtained with the aid of optical profilometer. The research was also carried out by investigations of surface wettability on the apparatus for measurements of contact angle. Characterization of Cu-Ti surface properties was also expanded by microbiological tests involving Staphylococcus aureus (PCM 2602) bacteria and investigations of cytotoxicity with L 929 (NCTC clone 929) cell line., Results: Measurements have shown that the film was composed of 71% at. Cu and 29% at. Ti. The analysis of surface topography has shown that the surface of Cu-Ti thin film was very uniform with roughness in range of nanometers. It was found that as-deposited film is hydrophilic. Obtained results has shown that as-deposited film had a very good bactericidal properties and it was cytotoxic. This effect was associated with the migration of copper ions, which was the most intense at the edge of the sample., Conclusions: The results presented in this paper testify that manufactured Cu-Ti thin films may find practical application in the industry as a bioactive coating.

Background: Titanium dioxide is widely used as a bacteriostatic and non-toxic material. It is important, therefore, to modify its properties, for greater biological activity., Objectives: The aim of this study was comparison of the specific surface properties and the biological activity of TiO2 and TiO2 with niobium and copper additives--TiO2:(Nb,Cu) thin films., Materials and Methods: TiO2 and TiO2:(Nb,Cu) thin films were prepared by high-energy magnetron sputtering of metallic Ti-Nb-Cu target in oxygen atmosphere. Films that have been deposited on glass substrates were investigated by transmission method and with the aid of optical profiler transparent. Besides, wettability measurements and antibacterial testes with Pseudomonas aeruginosa (PCM2058) were performed., Results: The light transmission characteristics have shown that the film with niobium and copper additives was less transparent than undoped titanium dioxide. Studies of surface geometric structure, performed with the aid of optical profilometer, have shown that coatings were uniform and the surface roughness had several nanometers. The roughness of TiO2:(Nb, Cu) was higher compared to the film of undoped TiO2. The wettability measurements have shown that (Nb, Cu) additives cause a significant reduction in the degree of surface wettability relative to TiO2 and the change of properties from hydrophilic to hydrophobic. The results of the microbiological tests have shown that the TiO2:(Nb, Cu) film had a very good antibacterial properties, while the undoped TiO2 did not exhibit such properties., Conclusions: The analysis of all results of carried investigations has shown that manufactured TiO2:(Nb,Cu) thin films can be used as a transparent antibacterial coating.