Incorporation of magnesium phosphate into magnesium oxide on Mg[sbnd]Ag alloy through plasma electrolytic oxidation.

The application of Mg Ag alloy for the fabrication of orthopedic implant requires its enhanced corrosion resistance, desired biocompatibility and bactericidal capability without cytotoxicity. Herein, to achieve those purposes, a novel plasma electrolytic oxidation (PEO) treatment was proposed. The PEO coating with a bimodal pore size distribution could form on Mg Ag alloy surface to enhance its corrosion resistance. Further, the incorporation of magnesium phosphate in the PEO coating may also benefit its biocompatibility. Finally, Ag within the alloy could be gradually oxidized to form incorporated Ag+ and nano-sized Ag 2 O particles in the coating, which potentially optimize the ionic release kinetics of Ag for a desired antibacterial capability without cytotoxicity. Hence, the present work offers a novel PEO method to improve the corrosion resistance and biological response of Mg Ag alloy, which enlightens the application of antibacterial Mg alloy in the field of biomedical devices. • An untraditional voltage response during the PEO process is reported. • Nano-sized magnesium phosphate is incorporated into the PEO coating. • Ag oxide nanoparticle is present in the PEO coating. • PEO coating with bimodal pore size distribution is produced. [ABSTRACT FROM AUTHOR]