Multifunctional CeO2/Graphene Nanoribbon Nanozyme for Synergistic Photothermal and Chemodynamic Therapy of Tumor

Nanozymes, simulating natural enzymatic actions, have shown substantial promise in catalytic tumor therapy. Nevertheless, developing nanozymes with multiple catalytic functions for multimodal nanodiagnosis remains a challenging task. Here, we report a type of quasi-one-dimensional graphene nanoribbons (GNRs) can firmly anchor and disperse CeO₂ nanoparticles by modifying polyethylene glycol (PEG) modification to form a stable CeO₂/GNRs-PEG nanocomposite. This material possesses multiple enzymatic activities, facilitating the transformation of H₂O₂ into hydroxyl radicals within the tumor environment, degrading H₂O₂ to produce O₂, and continuously converting O₂ into O₂^·– to increase oxidative stress in the tumor microenvironment. Notably, the good photothermal effect of CeO₂/GNRs-PEG can enhance the generation of ·OH and O₂^·–, increasing the level of oxidative stress within cells and thereby killing tumor cells. The ability of photothermal effects to enhance the generation of oxygen from hydrogen peroxide also leads to the production of more O₂^·– which can promote tumor ablation. Overall, multifunctional nanozymes loaded with GNRs present excellent promise as a catalytic therapy material in many fields.