Obtenção de filmes a-C:H via técnica PECVD na liga Ti6Al4V: caracterização estrutural e morfológica, eletroquímica e biológica

Abstract

With the purpose of improving the mechanical, chemical and biological properties of the Ti6Al4V alloy used as biomaterial, surface treatments are often performed. This work aims to investigate the biological responses of a-C:H films produced by PECVD technique onto substrate of Ti6Al4V alloy. The films produced were characterized morphologically and structurally by optical microscope (OM), SEM, AFM, EDX, FTIR Raman Spectroscopy (RS) and XPS. Afterwards, biocompatibility and cytotoxicity tests on osteoblastic cells and/or Human Peripheral Blood Mononuclear Cells (PBMCs) were performed on the Ti6Al4V alloy with coated and uncoated a-C:H film. The Ramam results exhibited a value of 0.71 for ID/IG ratio. The deconvoluted XPS spectra of C 1s peaks disclose the presence of three main components: C1 (284.4 eV) associated to C=C bounds in one sp2 hybridization as well as C2 (285.2 eV) associated to sp3 hybridization. The impedance results showed that a-C:H film acts as a protective barrier against the corrosion process in artificial saliva medium. Regardless of the cell population, when the total apoptosis of osteoblastic cells or PBMCs was evaluated, only cells cultured on the alloy without a-C:H had significant induction of the apoptotic process. Moreover, only PBMCs cultured on the alloy without a-C:H had significant induction of inflammatory and anti-inflammatory cytokines that characterize immune activation. The biological results from this study suggest that the strategy of use a-C:H film to cover the Ti6Al4V alloy promoted since its protection of the physiological environment to its biocompatibility improvement.