TiO2 rutile phase formed interlayers by sintering monophasic bioceramics for biomedical applications

Abstract

The formation of a rutile TiO₂ phase in nanohydroxyapatite (nanoHAP) coated titanium metal (nanHAP–TiO₂–Ti) is reported. This work is mainly carried out in order to enhance the corrosion protection performance, osseointegration and biocompatibility. The optimized potential of nanoHAP coated titanium using electrophoretic deposition (EPD) was found to be 80 V for 3 minutes. The coated samples were sintered in air at various sintering temperatures from 600 to 900 °C for 1 hour. The crystallinity, vibrational states, surface morphology and surface topography were characterized by XRD, Raman, FESEM with EDAX and AFM studies, respectively. In the present work, investigations on the corrosion behavior of sintered samples in Ringer's solution by means of electrochemical studies using open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and anodic polarization studies were carried out. The electrochemical studies exhibited an enhanced corrosion resistance behaviour of nanoHAP coated titanium sintered at 800 °C with complete rutile TiO₂ phase formation. In vitro cytotoxicity studies of the coated materials were carried out by MTT assay and cell attachment with osteoblast cells. These studies revealed enhanced cell attachment and proliferation on the composite layer compared to the uncoated metal, which controlled the release of metal ions into the biological system.