Au/CeO Nanozyme Scaffold Boosts Electron and Hydrogen Transfer for NIR-Enhanced Chemodynamic Therapy.

CeO nanozymes have demonstrated the potential to enhance biological scaffolds with chemodynamic therapy. However, their catalytic efficacy is limited by the slow conversion of Ce to Ce and the lack of substrates like HO and H. To address these challenges, we adopted a dual-pronged strategy that utilized the plasmonic resonance of Au nanoparticles and their glucose-oxidase mimicry to boost electron and hydrogen transfer. Specifically, we integrated Au/CeO nanozymes into poly-l-lactic acid scaffolds via selective laser sintering. This conversion of Ce to Ce in the scaffolds enhanced the reduction of HO to a hydroxyl radical, inducing oxidative stress in tumor cells. The Au nanoparticles played a crucial role in boosting the Ce/Ce catalytic cycle by providing both the energy and the catalytic substrates. They recycled Ce back to Ce by exploiting plasmonic-induced hot electrons and catalyzed glucose oxidation to supply HO and H. Our nanoscale and atomic-scale simulations confirmed that the Au/CeO hybrid structure utilized near-field coupling to amplify the plasmonic resonance and the Au-O-Ce bridge reduced the electron transfer barrier. Consequently, the Au/CeO scaffold decreased the activation energy from 22.57 to 9.92 kJ/mol. These findings highlight the significant promise of the Au/CeO nanozyme scaffold for NIR-enhanced chemodynamic therapy.