Gallium-Containing Materials and Their Potential within New-Generation Titanium Alloys for Biomedical Applications

Abstract

With the rising demand for implantable orthopaedic medical devices and the dominance of device-associated infections, extensive research into the development of novel materials has been prompted. Among these, new-generation titanium alloys with biocompatible elements and improved stiffness levels have received much attention. Furthermore, the development of titanium-based materials that can impart antibacterial function has demonstrated promising results, where gallium has exhibited superior antimicrobial action. This has been evidenced by the addition of gallium to various biomaterials including titanium alloys. Therefore, this paper aims to review the antibacterial activity of gallium when incorporated into biomedical materials, with a focus on titanium-based alloys. First, discussion into the development of new-generation Ti alloys that possess biocompatible elements and reduced Young’s moduli is presented. This includes a brief review of the influence of alloying elements, processing techniques and the resulting biocompatibilities of the materials found in the literature. The antibacterial effect of gallium added to various materials, including bioglasses, liquid metals, and bioceramics, is then reviewed and discussed. Finally, a key focus is given to the incorporation of gallium into titanium systems for which the inherent mechanical, biocompatible, and antibacterial effects are reviewed and discussed in more detail, leading to suggestions and directions for further research in this area.

Development of Novel Antibacterial Ti-Nb-Ga Alloys with Low Stiffness for Medical Implant Applications

“…Recent research has highlighted gallium’s effective antimicrobial properties without inducing cytotoxic effects [ 13 , 21 , 22 ]. Although many of the studies investigated the effect of Ga-doped materials such as glass and nanoparticle coatings rather than Ti-based systems, the antibacterial activity has nonetheless been documented [ 22 ].…”

“…Recent research has highlighted gallium’s effective antimicrobial properties without inducing cytotoxic effects [ 13 , 21 , 22 ]. Although many of the studies investigated the effect of Ga-doped materials such as glass and nanoparticle coatings rather than Ti-based systems, the antibacterial activity has nonetheless been documented [ 22 ]. For instance, Valappil et al [ 23 ] reported that Ga-doped phosphate-based glass exhibited potent antibacterial effects against five gram-negative and gram-positive bacteria strains, where even 1 mol% addition of Ga proved highly effective.…”