Dual-functionalized titanium for enhancing osteogenic and antibacterial properties

Bacterial infection and poor osseointegration of titanium implants are two of the main issues hindering their use in clinical applications. In order to solve these problems simultaneously, TiO2 nanotubes were fabricated, loaded with naringin (NA) and covered by gentamicin sulfate (GS)-inserted chitosan/gelatin bilayers through layer by layer technique. The successful system of the bifunctional titanium substrate was confirmed via scanning electron microscopy, atomic force microscope, water contact angle measurement, X-ray photoelectron spectroscopy and in vitro release of NA and GS. The multilayer-coated NA-loaded TiO2 nanotubes exhibited good biocompatibility as shown by cell morphology, cell viability assay, alkaline phosphatase activity, mineralization and qRT-PCR analysis of the osteogenesis related genes. Antibacterial experiments examining S. aureus and E. coli in vitro demonstrated that the bifunctional TiO2 nanotubes had antibacterial capabilities. Ihis approach provides a new and feasible strategy for improving the properties of titanium implants to promote osteogenic and antibacterial activity.