Coating of a biodegradable magnesium alloy for rapid action against S. aureus after ultraviolet exposition

• Published in: Applied surface science 2023-03, Vol.613, p.156006, Article 156006
• Main Authors: Tamurejo-Alonso, Purificación, Luisa González-Martín, M., Pacha-Olivenza, Miguel A.
• Format: Article
• Language: English
• Subjects: Antimicrobial; Biodegradable Mg alloys; Electrodeposition; Infection; Ultraviolet treatment
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2022.156006

[Display omitted] •Coatings on AZ31 were developed•The presence of zinc oxide was confirmed•An action against bacterial colonization was developed A new treatment was developed on AZ31 magnesium alloy to act against infection from its initial contact with a contaminated medium. The treatment was made with a coating of hydroxyapatite (HA), additional magnesium and zinc oxide activated with UV radiation before contact with the bacteria (HAMgZnUV). It was tested against Staphylococcus aureus, which is mainly responsible for early infections related to biomaterials. Because of the concurrent action of the UV effect plus the rapid release of Mg2+ from the coating, it provides an excellent action against bacterial colonization. After five hours of contact, the viability of planktonic and sessile bacteria on HAMgZnUV were reduced up to (99 ± 1)% respect to AZ31. In addition, mature biofilm growth for 24 h on HAMgZnUV decreased (90 ± 2)% respect to biofilm growth on AZ31. The research was performed on progressive coverages of AZ31, including HA, with magnesium (HAMg) or zinc (HAZn) or both (HAMgZn) added. The chemical composition of samples was characterized by XPS and ToF-SIMS, and the release of Mg2+ ions was done by ICP-MS. The presence of zinc as zinc oxide on the HAZn and HAMgZn coatings is confirmed, as well as better availability of magnesium from the HAMg and HAMgZn coatings.