Preparation of HA-MAO coatings on β-type alloys and its corrosion resistance in high glucose environments

Abstract

Aim to provide practical clinical guidance for the treatment of implants in diabetic patients, this study investigated the corrosion mechanism of bionic coatings containing different Ca/P ratios in diabetic environments. The bionic coatings were prepared in β-titanium alloys using micro-arc oxidation (MAO) technology and evaluated for corrosion mechanism, biocompatibility, and safety by cytotoxicity, electrochemical corrosion, and coating bonding force experiments. Ca and P from the electrolyte were integrated into the coating during MAO discharge process to form hydroxyapatite. The coating Ca/P ratio initially increased and then decreased with the electrolyte Ca/P ratio. In vitro cellular experiments demonstrated that increasing the porosity of HA-containing coatings would be beneficial to the growth of cells adhering to their surfaces. Corrosion tests revealed that the corrosion tendency of the coating at higher sugar content was more severe, and a proper elevation of the Ca/P ratio was better for the corrosion resistance of the coating. The bonding analysis of the coatings before and after corrosion showed that an increase in the Ca/P ratio would improve the bonding of the MAO coatings in higher glucose content environments, thus improving the safety of the implants in diabetic patients.