Engenharia Biomédica
URI permanente para esta coleçãohttps://repositorioacademico.universidadebrasil.edu.br/handle/123456789/915
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Item Modificação superficial da liga de Ti6Al7Nb por nanofilmes de Al2O3 e revestimento de fosfato de cálcio(Universidade Brasil, 2022) Sousa, Luciana Mendes Ribeiro de; Lobo, Anderson de Oliveira; Marciano, Fernanda RobertaThis work studied the surface modification of Ti6Al7Nb alloy treated by Al2O3 deposition by Atomic Layer Deposition (ALD) and apatite coating. This happened with four groups of samples: samples of substrates (group G1), samples treated by deposition of Al2O3 by ALD (group G2), samples with deposition of Al2O3 by ALD and coated with apatite by electroplating (group G3) and samples with deposition of Al2O3 by ALD and coated with apatite by immersion in a Simulated Body Fluid solution five times concentrated (SBF×5) (group G4). These groups were compared, resulting in the microstructural modification that provided a better biological response, in this case, the production of total proteins. The groups were characterized by X-ray fluorescence (FRX), Energy Dispersive X-Ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), X-Ray Diffraction Spectroscopy (XRD), Raman Spectroscopy and Atomic Force Microscopy (AFM). The characterizations revealed the chemical and crystallographic composition of the titanium alloy Ti6Al7Nb and after surface modifications, confirming the formation of aluminum-titanium (group G2) and aluminum-titanium-apatite (groups G3 and G4) films. The results revealed laminar apatite crystals in the form of plates, and irregular crystals, with the appearance of flakes growing from the center to the edge and looking like flowers. The sizes and crystallinity indices, as well as the Ca/P ratio showed values within the expected range for biological, synthetic and non-stoichiometric apatites. In vitro cytotoxicity assays and quantification of total proteins related to calcification of the extracellular matrix were performed and showed that the untreated alloy had higher cellular affinity, as can be seen in the G1 group, however, the Ti6Al7Nb surface modifications by Al2O3 nanofilms by ALD and apatites improved bioactivity and protein production as shown by experimental groups G2, G3 and G4. The formation of microporosity was favorable to the greater production of total proteins, as observed in the G2 group. Furthermore, it influenced the nucleation of apatites at the nanoscale, as shown by the G3 and G4 groups. The results presented in this work confirmed the non-cytotoxicity, strongly supporting the application of these nanofilms in tissue engineering.