Improving in vitro and in vivo antibacterial functionality of Mg alloys through micro-alloying with Sr and Ga

Publication date: November 2019Source: Materials Science and Engineering: C, Volume 104Author(s): Zhihan Gao, Mingshi Song, Rui-Liang Liu, Yongshuai Shen, Liam Ward, Ivan Cole, Xiao-Bo Chen, Xinchun LiuAbstractDespite of technical advancements in design and development of new biomaterials, device-related infections continue to occur and can be life-threatening. Differing from existing research work pertaining to introducing antibacterial function upon device surface, this study attempts to address such germ-infection issues through controlled release of antibacterial species from bulk gallium (Ga) and strontium (Sr) containing magnesium (Mg) alloys. To validate such a conceptual framework, Mg alloys containing micro-level concentrations of Ga and/or Sr (0.1 wt%) are employed as model materials, along with commercially pure Mg and titanium (Ti) as control groups. Biodegradation progress of such metal specimens is examined through pH and mass loss measurements, and inductively coupled plasma - atomic emission spectrometry (ICP-AES) as a function of immersion time in Trypticase Soy Broth (TSB) solution under physiological conditions. In vitro biocompatibility and antibacterial performance are characterised through MTT proliferation assay with human mesenchymal stem cells (hMSCs) and the spread plate method with three representative bacterial strains, i.e. S. aureus (ATCC 43300), E. coli (ATCC 25922), and S. epidermidis (ATCC 35984). Animal tests are performed through implantin...
Source: Materials Science and Engineering: C - Category: Materials Science Source Type: research