Platelet Membrane-Camouflaged Copper Doped CaO₂ Biomimetic Nanomedicines for Breast Cancer Combination Treatment

Breast cancer (BC) is the most frequently diagnosed cancer in women worldwide. Chemodynamic therapy (CDT), photothermal therapy (PTT), and ion interference therapy (IIT), used in combination, represent a common treatment. In this study, platelet membrane-camouflaged copper-doped CaO₂ biomimetic nanomedicines have been developed for breast cancer treatments. Copper-doped CaO₂ nanoparticles were first coated by polydopamine (PDA) and subsequently camouflaged by platelet membrane (PM) to form platelet membrane-camouflaged copper doped CaO₂ biomimetic nanomedicines (Cu-CaO₂@PDA/PM). The as-fabricated Cu-CaO₂@PDA/PM multifunctional nanomedicines could decompose within the tumor microenvironment to release Ca²⁺ for ion interference therapy, and the generated H₂O₂ could perform a Fenton-like reaction with the assistance of loaded copper ions to produce ·OH, thus realizing chemodynamic therapy. In addition, the copper ions could also consume glutathione and weaken its ability to scavenge reactive oxygen species, which was conducive to amplifying the effect of oxidative stress. The coating of the polydopamine layer could achieve local hyperthermia of the tumor site, and the surface modification of the platelet membrane could enhance the targeting and biocompatibility of nanomedicines. <i>In vivo</i> and <i>in vitro</i> tests demonstrated that the developed Cu-CaO₂@PDA/PM biomimetic nanomedicines offer a promising biomimetic nanoplatform for efficient multimodal combination therapy for breast cancer.