A novel Ti-Au alloy with strong antibacterial properties and excellent biocompatibility for biomedical application

In order to avoid the toxic and side effects on human body of long-term dissolution of metal ions from antibacterial titanium alloys, Au element with non-toxicity and non-side effect was selected as the alloying element to prepare a new Ti-Au alloy with strong antibacterial property. We produced Ti-Au(S) sintered alloy by powder metallurgy and Ti-Au ingot alloy by ingot metallurgy, and investigated the influence of the secondary phase on the relative antimicrobial properties and antibacterial mechanism in this work. The results indicated that the aged Ti-Au(T6) alloy and Ti-Au(S) sintered alloy exhibited strong antibacterial rate against S. aureus due to the formation of Ti₃Au phases. In vitro cell culture (MC3T3 cells) experiments showed that Ti-Au alloys had good cytocompatibility and osteogenic properties. The following viewpoints of antibacterial mechanism are that the Ti₃Au destroyed the ROS homeostasis of bacteria, causing oxidative stress in bacterial cells and preventing from the biofilms formation.