title: Enhanced antimicrobial properties, cytocompatibility, and corrosion resistance of plasma-modified biodegradable magnesium alloys.
abstract: Magnesium alloys are potential biodegradable materials and have received increasing attention due to their outstanding biological performance and mechanical properties. However, rapid degradation in the physiological environment and potential toxicity limit clinical applications. Recently, special magnesium-calcium (Mg-Ca) and magnesium-strontium (Mg-Sr) alloys with biocompatible chemical compositions have been reported, but the rapid degradation still does not meet clinical requirements. In order to improve the corrosion resistance, a rough, hydrophobic and ZrO(2)-containing surface film is fabricated on Mg-Ca and Mg-Sr alloys by dual zirconium and oxygen ion implantation. Weight loss measurements and electrochemical corrosion tests show that the corrosion rate of the Mg-Ca and Mg-Sr alloys is reduced appreciably after surface treatment. A systematic investigation of the in vitro cellular response and antibacterial capability of the modified binary magnesium alloys is performed. The amounts of adherent bacteria on the Zr-O-implanted and Zr-implanted samples diminish remarkably compared to the unimplanted control. In addition, significantly enhanced cell adhesion and proliferation are observed from the Zr-O-implanted sample. The results suggest that dual zirconium and oxygen ion implantation, which effectively enhances the corrosion resistance, in vitro biocompatibility and antimicrobial properties of Mg-Ca and Mg-Sr alloys, provides a simple and practical means to expedite clinical acceptance of biodegradable magnesium alloys.
authors.affiliation: Department of Orthopaedics & Traumatology, The University of Hong Kong, Pokfulam Road, Hong Kong, China; Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhao
authors.forename: Mohammed Ibrahim
authors.initials: MI
authors.lastname: Jamesh
authors.forename: Wing Kan
authors.initials: WK
authors.lastname: Li
authors.forename: Guosong
authors.initials: G
authors.lastname: Wu
authors.forename: Chenxi
authors.initials: C
authors.lastname: Wang
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Zheng
authors.forename: Kelvin W K
authors.initials: KW
authors.lastname: Yeung
authors.forename: Paul K
authors.initials: PK
authors.lastname: Chu
mesh_terms: D000497:Alloys / Q000494:pharmacology*; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003343:Corrosion; D058266:Dielectric Spectroscopy; D020007:Implants, Experimental; D008274:Magnesium / Q000494:pharmacology*; D051379:Mice; D008826:Microbial Sensitivity Tests; D018625:Microscopy, Atomic Force; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D056951:Photoelectron Spectroscopy; D058626:Plasma Gases / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D000497:Alloys; D000890:Anti-Infective Agents; D058626:Plasma Gases; D014867:Water; D008274:Magnesium
keywords: Biodegradable; Corrosion; Cytocompatibility; Interfaces; Magnesium alloy