Metal-Phenolic Chemistry Mediates Assembly of Single-Atom Nanozymes for Cancer Therapy

Metal-phenolic networks (MPNs) composed of metal ions and polyphenols have gained significant attention as promising approaches for material engineering due to the diverse properties of the ligands and metal ions. Herein, we present a versatile approach for the synthesis of single-atom nanozymes (SAzymes) based on metal-phenolic chemistry. By leveraging the chelating properties of polyphenols with various metal ions, we synthesized a variety of SAzymes (e.g., Fe, Cu, Mn, and Co) via coating metal–organic frameworks with MPNs, followed by pyrolysis. In particular, the engineered Fe single-atom-incorporated nanoparticles, with an FeN5 nanostructure, exhibit exceptional peroxidase-like activity. This feature makes the engineered FeN5 SAzymes a potent tool for suppressing tumor cell growth through a synergistic effect with glucose oxidase. This research highlights the desirable coordination chemistry between metal ions and polyphenols for the engineering of SAzymes in biological applications.