Graphene Oxide as a Potent Photothermal-Sensitizer for Near-Infrared Laser Therapy in Oral Cancer: An In-Vitro Efficacy and Protocol Optimization Study

Developing innovative nanomaterials for anti-cancer therapies is critical in contemporary oncological research. Graphene oxide (GO), owing to its unique physicochemical properties, shows significant promise as a photothermal sensitizer for near-infrared (NIR) laser therapy, particularly for aggressive malignancies like oral cancer, where conventional treatments often cause damage to healthy tissues. This study presents a comprehensive in vitro investigation into the efficacy of GO-mediated photothermal therapy (PTT) and, crucially, delineates a novel, optimized protocol for its application against human tongue carcinoma cells (HNO97). GO was synthesized via an improved Hummer's method. For PTT, HNO97 cells were incubated with 50 µg/mL GO prior to irradiation with a 980 nm NIR diode laser. The optimized protocol involved two irradiation sessions, each lasting 5 minutes at a 400 mW/cm² power density, separated by a one-hour interval. This novel GO+laser regimen resulted in a substantial, statistically significant cytotoxic effect, achieving approximately 82.5% cell death in HNO97 tongue carcinoma cells. In contrast, laser irradiation alone under the same conditions induced only minimal toxicity (approximately 12.4% cell death) and GO alone at 50 µg/mL showed high biocompatibility. These findings underscore the potent synergistic effect of GO with NIR light under precisely defined parameters and highlight the novelty of the optimized irradiation strategy in maximizing therapeutic efficacy. This study provides foundational evidence for future photothermal therapy protocols for GO-based PTT in oral cancer, emphasizing protocol optimization for developing effective, multipurpose nanomedical solutions and warranting further preclinical validation of these promising optimized conditions.