Single-Atom Pd Nanozyme for Ferroptosis-Boosted Mild-Temperature Photothermal Therapy

Photothermal therapy (PTT) is an extremely promising tumor therapeutic modality. However, excessive heat inevitably injures normal tissues near tumors, and the damage to cancer cells caused by mild hyperthermia is easily repaired by stress-induced heat shock proteins (HSPs). Thus, maximizing the PTT efficiency and minimizing the damage to healthy tissues simultaneously by adopting appropriate therapeutic temperatures is imperative. Herein, an innovative strategy is reported: ferroptosis-boosted mild PTT based on a single-atom nanozyme (SAzyme). The Pd SAzyme with atom-economical utilization of catalytic centers exhibits peroxidase (POD) and glutathione oxidase (GSHOx) mimicking activities, and photothermal conversion performance, which can result in ferroptosis featuring the up-regulation of lipid peroxides (LPO) and reactive oxygen species (ROS). The accumulation of LPO and ROS provides a powerful approach for cleaving HSPs, which enables Pd SAzyme-mediated mild-temperature PTT.