Photosensitizer and TiO2 were co-loaded on graphene oxide to be used as drug delivery system. The system has mutual sensitization mechanism to generate more reactive oxygen species than free photosensitizer, and therefore, improve its phototoxicity to cancer cells. Interestingly, the system can be self-degraded after photodynamic process.
In this manuscript, a photosensitive anti-cancer drug, hypocrellin A (HA), and TiO2 nanoparticles were co-loaded on the surface of graphene oxide (GO) as a photosensitive drug delivery system. In vitro studies have demonstrated the active uptake of the system into the mitochondrial of tumor cells. Such system has mutual sensitization mechanism to greatly improve the reactive oxygen species (ROSs) generation ability of the complex by visible light irradiation and, thereby, the strong photodynamic therapy (PDT) efficacy. Furthermore, during such PDT process, GO can be destroyed by the ROSs, which would helpful for the metabolism of this drug delivery system.