Ag-containing antibacterial self-healing micro-arc oxidation coatings on Mg–Zn–Sr alloys

ABSTRACT

The rapid degradation rate restricts the application of magnesium-based biomaterials. Therefore, we constructed Ag-containing micro-arc oxidation (MAO) coatings on Mg–3Zn–0.5Sr alloys to improve the properties of magnesium alloys. Different concentrations of CH₃COOAg (0, 1, 2, 3 g L⁻¹) were added into the electrolyte to investigate the effects of Ag⁺ content on properties of MAO coatings. The addition of CH₃COOAg led to the formation of Ag₂O and Ag₂CO₃ phases, which sealed the micro-pores and improved the corrosion resistance of the samples significantly. The samples with addition of 2 and 3 g L⁻¹ CH₃COOAg exhibited strong antibacterial ability against E.coli due to the gradual release of Ag⁺ in the degradation process. It was verified that the samples with addition of 2 g L⁻¹ CH₃COOAg obtained the most high bonding strength, dense construction, excellent corrosion resistance, cytocompatibility and antibacterial properties. The bacteria-killing methods of Ag-containing MAO coatings were discussed in the article.

KEYWORDS:

• Self-sealing
• antibacterial
• anti-corrosion
• cytocompatibility
• Ag
• magnesium
• biomaterial
• micro-arc oxidation

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data accessibility

All relevant data were within the paper.

Additional information

Funding

This work was financially supported by Shandong Provincial Natural Science Foundation [grant number ZR2017MEE063], the Key R&D project of Shandong Province [grant no. 2018CXGC0811], Natural Science Foundation of Jiangsu Province [grant no. SBK2020040524], China Postdoctoral Science Foundation Funded Project [grant no. 2019M652184] and China Postdoctoral Science Foundation Special Funded Project [grant no. 2019T120589].