"Three-in-One" Nanozyme Composite for Augmented Cascade Catalytic Tumor Therapy.

Cascade catalytic reaction exhibits simple procedure and high efficiency, such as that from the orderly assembly of different enzymes in biological systems. Mimicking of the natural cascade procedure becomes critical, but the orderly assembly of different enzymes is still challenging. Herein, we reported single Au-Pt nanozyme with "three-in-one" functions to initiate cascade conversions for O2 supply as mimic catalase, H2O2 production with its glucose oxidase-like property, and •OH generation as mimic peroxidase for chemodynamic therapy (CDT). Thus, the complex assembly and cross-talk among the different enzymes are avoided. To this end, metastable Cu2O NPs, as scaffolds, are used to anchor ultrasmall Au-Pt nanozyme, while metal-organic framework (MOF) is used to encapsulate the nanozyme for tumor microenvironment (TME) response and shielding protein adsorption. Pluronic® F127 is then modified on the surface to improve hydrophilicity and biocompatibility of the composite. The endogenous acidity and glutathione in tumor degrade MOF to expose nanozyme for cascade catalytic CDT. The high photothermal conversion ability of the composite also enhances the CDT, while Cu2+ ions consume GSH to further improve CDT efficiency as augmented cascade catalytic tumor therapy. Thus, we provide a new paradigm with drug-free single nanozyme for improving tumor therapeutic efficacy and minimizing side effects. This article is protected by copyright. All rights reserved.