Bioinspired Macrophage‐Camouflaged Oxygen‐Self‐Supplying Nanoplatform for Precision Synergistic Ablation of Breast Cancer

Breast cancer remains one of the most prevalent and life‐threatening malignancies affecting women globally, and the development of precision therapeutic platforms capable of overcoming the inherent limitations of conventional monotherapies is a pressing clinical imperative. Here, we report the design, synthesis, and evaluation of a macrophage membrane‐camouflaged IrO 2 ‐IR808 nanoplatform (IrO 2 ‐IR808@M1) that achieves precise and synergistic tumor ablation through the cooperative action of photothermal/photodynamic therapy (PDT). The IrO 2 nanocore provides efficient light‐to‐heat conversion and catalase‐like activity that locally generates oxygen to sustain PDT efficacy in the hypoxic tumor microenvironment, while the covalently conjugated near‐infrared (NIR) photosensitizer IR808 provides complementary NIR absorption and reactive oxygen species (ROS) generation. Under 808 nm NIR irradiation, IrO 2 ‐IR808@M1 achieves rapid and reproducible temperature elevation with a high photothermal conversion efficiency (PCE) of 55.22%, translating into potent concentration‐dependent cytotoxicity in MCF‐7 breast cancer cells and pronounced tumor growth suppression in syngeneic 4T1 murine models without discernible systemic toxicity. The M1 macrophage membrane camouflage confers extended systemic circulation, enhanced colloidal stability, and strengthened tumor selectivity through immune‐mimetic surface interactions. This bioinspired, self‐oxygen‐supplying nanoplatform establishes a concise and translatable blueprint for precision phototherapy in breast cancer, with implications for broader application across solid tumor indications.