Near‐Infrared‐II Light Induced Mild Hyperthermia Activate Cisplatin‐Artemisinin Nanoparticle for Enhanced Chemo/Chemodynamic Therapy and Immunotherapy

Abstract Chemodynamic therapy (CDT) is an effective cancer treatment that uses Fenton reaction to induce cancer cell death. Current clinical applications of CDT are limited by the dependency of external supply of metal ions as well as low catalytic efficiency. Here, a highly efficient metal‐free CDT by using endoperoxide bridge‐containing artesunate as free radical‐generating substance is developed. A Pt(IV) prodrug (A‐Pt) containing two artesunate molecules in the axial direction is synthesized, which can be decomposed into cisplatin and artesunate under reducing intracellular environment in tumor cells. To improve the catalytic efficiency for Fenton reaction, a near‐infrared‐II (NIR‐II) photothermal agent IR1048 is incorporated to achieve a mild hyperthermia effect. By encapsulating the A‐Pt and IR1048 with human serum albumin, A‐Pt‐IR NP are formulated for efficient drug delivery in 4T1 tumor‐bearing mice. NIR‐II light irradiation of A‐Pt‐IR NP treated mice show accelerated Fenton reaction. In addition, A‐Pt‐IR NP could also induce strong immunogenic cell death, which effectively reverses the immunosuppressive tumor microenvironment, and augments antitumor immunity. This study demonstrates that A‐Pt‐IR NP are potent biodegradable NIR‐II active chemotherapy/CDT nanomedicine for clinical translation.