Graphene Oxide-Modified Titanium Dioxide Nanotubes Promote Schwann Cell Function and Neurotrophic Factor Expression

This study aims to investigate the effects of graphene oxide-modified titanium dioxide nanotube (TNT-GO) coatings on the biological behavior of Schwann cells and to evaluate their potential applications in dental implant surface modification and peripheral nerve regeneration. Titanium dioxide nanotubes (TNTs) were prepared by anodic oxidation, and graphene oxide (GO) was deposited on their surfaces by electrochemical deposition. The surface morphology and physicochemical properties were characterized by scanning electron microscopy (SEM), Raman spectroscopy, atomic force microscopy, X-ray diffraction, and contact angle measurements. The viability, proliferation, and adhesion of Schwann cells were assessed by cell counting kit-8 assay, live/dead staining, and SEM observation. The expression levels of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) were evaluated by immunofluorescence staining and real-time reverse-transcriptase polymerase chain reaction. The results indicated that TNT-GO surface significantly improved surface hydrophilicity and biocompatibility. Compared with the Ti and TNT groups, Schwann cells on TNT-GO surfaces exhibited enhanced proliferation, better spreading morphology, and significantly increased expression levels of NGF and GDNF. Overall, TNT-GO effectively promotes Schwann cell proliferation, adhesion, and neurotrophic factor secretion, suggesting its potential as a novel surface modification strategy to promote peri-implant nerve regeneration and improve osseoperception.