Y-doped TiO2 coating with superior bioactivity and antibacterial property prepared via plasma electrolytic oxidation

To improve the bioactivity and antibacterial properties of implant materials. In this study, the biomedical titanium alloy (Ti-6Al-4V) was covered by yttrium doped titanium dioxide (Y-TiO2) coating via a plasma electrolytic oxidation (PEO) method. By changing the concentration of yttrium acetate in the electrolyte, Y-TiO2 coating with different mass ratios of yttrium were obtained. The structure morphology and chemical composition of the Y-TiO2 coating were systematically characterized. The results indicated that the porous and micro-nanostructured Y-TiO2 coatings were constructed by the pores smaller than 4 mu m. Definitely yttrium was not only distributed on the surface but also embedded in the coating. Yttrium mainly existed in form of Y2O3 and Y3+ state in prepared TiO2 coating. Element release profiles confirmed that yttrium release slowly from Y-TiO2 for 32 days. Cell culture tests demonstrated that Y-TiO2 coating exhibited good biocompatibility on osteoblastic precursor cells and fibroblasts cells with increasing doping concentration of yttrium. Bacteriostasis experiments revealed that Y-TiO2 coating possess excellent antibacterial property against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Thus, the prepared Y-TiO2 coating with outstanding biocompatibility and antibacte-rial capacity provided a preferred strategy for the repair and reconstruction of bone tissues in dentistry and orthopedics. (C) 2020 Published by Elsevier Ltd.