The Effect of Titanium Dioxide Nanotubes and Graphene Compounds on the Proliferation and Osteogenic Differentiation of Rat BMSCs

Graphene-based nanomaterials, including graphene oxide (GO) and graphene quantum dots (GQDs), exhibit exceptional properties, which might facilitate the functional modification of TiO₂ nanotubes (NTs) for enhanced rapid osseointegration. This study investigated the effects of GO/GQD-deposited TiO₂-NTs on cell proliferation, osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs), and early osseointegration in male 6-week-old Sprague Dawley (SD) rats. TiO₂-NTs (control group) were fabricated on titanium substrates via anodic oxidation. GO and GQDs were electrochemically deposited onto the TiO₂-NTs using cyclic voltammetry with 0.5 mg/mL GO and 0.1 mg/mL GQD dispersions to form NT-GO and NT-GQDs. In vitro assays evaluated cell adhesion, proliferation, and osteogenic differentiation. Implants were randomly inserted into one femoral epiphysis of nine rats (<i>n</i> = 3), and osseointegration was evaluated using micro-computed tomography and sequential fluorescence labeling at 2, 4, and 6 weeks post-implantation. Statistical analysis was conducted using ANOVA. Cyclic voltammetry successfully synthesized NT-GO and NT-GQDs, with Raman spectra confirming D and G bands. Both NT-GO and NT-GQDs exhibited superior cell adhesion, proliferation, and enhanced osteogenic differentiation compared with TiO₂-NTs. Notably, the NT-GQDs significantly promoted new bone formation in vivo. The integration of graphene nanomaterials onto TiO₂-NTs improves biocompatibility and accelerates osteogenesis, suggesting a promising strategy for enhancing osseointegration in orthopedic and dental implants.