Novel hollow ultrasound-triggered ZnFe2O4-Bi2MoO6 S-scheme heterojunction for efficient ferroptosis-based tumor therapy.

This study addresses the challenge of enhancing ferroptosis efficacy for tumor therapy, particularly the limited therapeutic efficiency of current inducers due to tumor microenvironment constraints. Herein, we developed a hollow ultrasound-triggered ZnFe₂O₄-Bi₂MoO₆ (ZB) S-scheme heterojunction loaded with artesunate (ART) to overcome these limitations. The ZB heterojunction with a particle size of ∼250 nm efficiently separates electron-hole pairs under ultrasound (US), promoting the generation of reactive oxygen species (ROS). The photodynamic effect of ZB further boosts ROS production, while ART, controlled-released by phase change materials under laser/US stimulation, enhances ROS production via Fe²⁺-mediated decomposition. This triple-enhanced strategy accumulates lipid peroxidation (LPO), significantly improving ferroptosis effects with a tumor suppression rate of 94.3 %. Moreover, ZB enables multimodal imaging and stimulates antitumor immunity, demonstrating its potential as a diagnostic and therapeutic agent. Our findings demonstrate the potential of this ZB@ART system in advancing ferroptosis-based tumor therapies, inspiring future designs of efficient ferroptosis inducers.