Osteogenic and antibacterial ability of micro-nano structures coated with ZnO on Ti-6Al-4V implant fabricated by two-step laser processing

The biological performance of Ti-6Al-4V implant is primarily determined by their surface properties. However, traditional surface modification methods, such as acid etching, hardly make improvement in their osseointegration ability and antibacterial capacity. In this study, we prepared a multi-scale composite structure coated with zinc oxide (ZnO) on Ti-6Al-4V implant by an innovative technology of two-step laser processing combined with solution-assistant. Compared with the acid etching method, the physicochemical properties of surface significantly improved. The in vitro results showed that the particular dimension of micro-nano structure and the multifaceted nature of ZnO synergistically affected MC3T3-E1 osteogenesis and bacterial activities: (1) The surface morphology showed a 'contact guidance' effect on cell arrangement, which was conducive to the adhesion of filopodia and cell spreading, and the osteogenesis level of MC3T3-E1 was enhanced due to the release of zinc ions (Zn2+); (2) the characterization of bacterial response revealed that periodic nanostructures and Zn2+ released could cause damage to the cell wall of E. coli and reduce the adhesion and aggregation of S. aureus. In conclusion, the modified surface showed a synergistic effect of physical topography and chemical composition, making this a promising method and providing new insight into bone defect repairment. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

In this study, a multi-scale composite structure coated with zinc oxide was prepared on Ti-6Al-4V implant using an innovative technology. Compared with traditional acid etching, the surface properties were significantly improved. The in vitro results demonstrated that the modified surface with specific micro-nano structures and release of zinc ions had a synergistic effect on osteogenesis and bacterial activities.