An O2 Self-Sufficient Biomimetic Nanoplatform for Highly Specific and Efficient Photodynamic Therapy

Conventional oxygen-dependent photodynamic therapy (PDT) has faced severe challenges because of the non-specificity of most available photosensitizers (PSs) and the hypoxic nature of tumor tissues. Here, an O 2 self-sufficient cell-like biomimetic nanoplatform (CAT-PS-ZIF@Mem) consisting of the cancer cell membrane (Mem) and a cytoskeleton-like porous zeolitic imidazolate framework (ZIF-8) with the embedded catalase (CAT) protein molecules and Al(III) phthalocyanine chloride tetrasulfonic acid (AlPcS 4 , defined as PS) is developed. Because of the immunological response and homologous targeting abilities of the cancer cell membrane, CAT-PS-ZIF@Mem is selectively accumulated at the tumor site and taken up effectively by tumor cells after intravenous injection. After the intracellular H 2 O 2 penetration into the framework, it is catalyzed by CAT to produce O 2 at the hypoxic tumor site, facilitating the generation of toxic 1 O 2 for highly effective PDT in vivo under near-infrared irradiation. By integrating the immune escape, cell homologous recognition, and O 2 self-sufficiency, this cell-like biomimetic nanoplatform demonstrates highly specific and efficient PDT against hypoxic tumor cells with much reduced side-effect on normal tissues.