Ti-6Al-4V-5Cu synthesized for antibacterial effect in vitro and in vivo via contact sterilization

Implant-related infection is one of the most catastrophic complications after surgery, since it may trigger osteomyelitis and necessitate reoperation, increasing the pain suffered by and the burden placed on the patient. Producing a new alloy with an antibacterial effect for use as a biomedical material is an urgent requirement. In this article, Ti-6Al-4V-5Cu was synthesized under two different heat treatment schemes (solution temperatures of 850°C and 950°C). Through comprehensive observation of the microstructure, phase, copper ion release, biocompatibility, corrosion resistance and antibacterial effect in vitro and in vivo, it was determined that cell viability and corrosion resistance of Ti-6Al-4V-5Cu was better than Ti-6Al-4 V. More importantly, the obtained alloy, especially samples treated at 850°C, showed prominent antibacterial ability. Meanwhile, we also found that the main antibacterial mechanism of the alloy was contact sterilization via the extensive precipitation of Ti2Cu instead of Cu ion release, and the content, surface area of Ti2Cu could affect the antibacterial effect. These findings provide a very promising scheme by which to balance the biocompatibility and antibacterial effect of Ti-based, Cu-bearing alloys, which could improve their performance in orthopedic and dental applications.