The preparation of reduced graphene oxide and its photothermal therapy of gliomas in vivo and in vitro

Objective: To investigate the preparation of reduced graphene oxide (reduced-NGO) and its photothermal therapy of gliomas in vivo and in vitro. Methods: Hydrazine hydrate reduction method was used to reduce graphene oxide (NGO). The morphology, diameter, stability and UV-VIS absorbance of reduced-NGO were detected firstly; and then, the photothermal conversion effect of reduced-NGO under 2 w/cm2 808 nm irradiation was tested. MTT method was used to detect the effect of reduced-NGO alone and reduced-NGO combined with 808 nm near-infrared laser (NIR) irradiation on cell viability. Lastly, the photothermal therapeutic effect of reduced-NGO for treating U87 tumor in vivo was detected. Results: Reduced-NGO obtained by hydrazine hydrate reduction method was lamellar particle with a diameter of 90 nm, which showed strong NIR absorbance, great stability and biocompatibility. The temperature of reduced-NGO solution could reach 70°C under 2 w/cm2 808 nm irradiation for 5 min. Reduced-NGO combined with 2 w/cm2 808 nm irradiation could significantly inhibit cell viability and tumor growth. Conclusion: Herein, we successfully synthesized reduced-NGO which showed good tumor killing effect in vitro and in vivo and no toxicity when combined with 808 nm radiation.