Antibacterial property of graphene quantum dots-modified TiO2 nanorods on titanium dental implant

Graphene quantum dots (GQDs) were incorporated into TiO2 nanorods (TiO2 NR) by hydrothermal treatment to prevent bacterial infections of Ti implants. The successful preparation of TiO2 NR doped with GQDs on Ti was confirmed by scanning electron microscopy, high-resolution transmission electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and Fourier transform infrared spectrometer. Results showed that the mean diameter of the nanorod was 60 nm, and the hydrophilicity was significantly improved. The GQDs-modified TiO2 NR showed excellent antimicrobial effect against Streptococcus mutans with an efficiency of 97.8% due to the combined effect of GQDs and nanorod structure. Moreover, GQDs-modified TiO2 NR exhibited good biocompatibility and osteogenetic potency for cell spreading, thus contributing to the new bone formation even in bacteria-induced implant infection.