A glutathione responsive nanoplatform made of reduced graphene oxide and MnO2 nanoparticles for photothermal and chemodynamic combined therapy

Abstract

Based on the specific tumor microenvironment, characterized by an overproduction of H2O2 and a high glutathione (GSH) concentration, the cascade reactions of nanomaterials, capable of mediating GSH depletion and reactive oxygen species (ROS) generation, have become a popular strategy to increase cancer therapy efficiency. In this study, we exploited reduced graphene oxide (rGO), one of the most promising graphene-based materials, in combination with manganese dioxide nanoparticles (MnO2 NPs) to design a multifunctional nanoplatform (rGO@MnO2) for efficient photothermal/chemodynamic combined therapies. MnO2 NPs were anchored onto the surface of rGO nanosheets (rGO NSs). MnO2 NPs oxidize intracellular GSH, and the generated Mn2+ ions converted H2O2 into HO by Fenton reaction. Meanwhile, rGO NSs mediated photothermal therapy (PTT) could further kill cancer cells. High temperature caused by photothermal conversion increased Fenton reaction rate, which enhanced the efficiency of MnO2 NPs mediated chemodynamic therapy (CDT). Importantly, thanks to the enhanced cell uptake of MnO2 NPs favored by the delivery properties of rGO, rGO@MnO2 possessed higher lethality to cancer cells. The decrease in the nanomaterials’ effective dose would further improve biosecurity and reduce cost. Therefore, rGO@MnO2 have great potential in cancer therapy by exploiting the synergistic effect of PTT and photothermal/delivery effect enhanced CDT.