WEB Regulation of Alkaline Microenvironment on Titanium Surface and Its Biological EffectsWednesday (23.09.2020) 09:00 - 09:30 B: Biomaterials Part of:
Titanium and its alloys are preferred for hard tissue implant materials, however, their inherent bioinertia cause poor osseointegration. Besides, they is lack of antibacterial ability, which results in the risk of implant-related infections. It is well known, the biological effects of implant materials are related to their surface microenvironment. Therefore, it is significant to explore the effect of the surface microenvironment on the behaviors of bacteria and cells. The pH value of the microenvironment is significant to the behaviors of bacteria and cells. And in general, weakly acidic microenvironment is beneficial to the survival of bacteria, and weakly alkaline microenvironment is conducive to bone formation. Therefore, constructing functional coating with tunable alkaline microenvironment on titanium is expected to endow it selective antibacterial and osteogenic abilities. From this perspective, various alkaline coatings were constructed on the surface of biomedical titanium via hydrothermal synthesis, ion implantation, and magnetron sputtering technology, and the effect of the surface alkaline microenvironment of them on the behaviors of bacteria and osteogenic cells were investigated. The results showed that alkaline surface microenvironment can inhibit the respiratory activity of both gram-positive and negative bacteria, resulting in the death of bacteria. The underlying antibacterial mechanism was further verified to primarily correlate with the disruption of respiratory electron transport chain and generation of oxidative stress of bacteria. Besides, an appropriate alkaline surface microenvironment can promote the osteogenic differentiation of bone marrow mesenchymal stem cells and the proliferation of osteoblast cells. This study has proposed a novel strategy of regulating surface alkalinity to endow implant materials with selective antibacterial and osteogenic abilities, which has broad prospects of clinical application in bone repair.