Advanced Functional Materials, 4 January, 2022. DOI: https://doi.org/10.1002/adfm.202110268

H₂O₂ Self-Producing Single-Atom Nanozyme Hydrogels as Light-Controlled Oxidative Stress Amplifier for Enhanced Synergistic Therapy by Transforming “Cold” Tumors

Daoming Zhu, Hao Chen, Chunyu Huang, Guoxin Li, Xing Wang, Wei Jiang, Kelong Fan

Abstract

Single-atom nanozyme (SAzyme) with peroxidase-like activity can alter cellular redox balance and shows promising potential for tumor therapy. However, the “cold” immune microenvironment and limited amount of hydrogen peroxide (H₂O₂) in solid tumors severely restrict its efficacy. Herein, a light-controlled oxidative stress amplifier system is designed by co-encapsulating Pd-C SAzymes and camptothecin in agarose hydrogel, which exhibits enhanced synergistic antitumor activity by self-producing H₂O₂ and transforming “cold” tumors. In this nanozyme hydrogel system, the Pd-C SAzyme converts near-infrared laser into heat, resulting in agarose degradation and consequent camptothecin release. The camptothecin increases H₂O₂ level in tumors by activating nicotinamide adenine dinucleotide phosphate oxidase, improving the catalytic performance of SAzymes with peroxidase-like activity. Moreover, the combination of photothermal therapy, chemotherapy, and nanozyme-based catalytic therapy further facilitates tumor immunogenic death and enhanced antitumor immunity. The results reveal the synergistic antitumor potential of the novel SAzyme/chemotherapeutics-based hydrogel system.

Article link：https://onlinelibrary.wiley.com/doi/10.1002/adfm.202110268