Metal–Organic Frameworks with Enhanced Photodynamic Therapy: Synthesis, Erythrocyte Membrane Camouflage, and Aptamer-Targeted Aggregation

Here, ferric oxide-loaded metal-organic framework (FeTCPP/Fe₂O₃ MOF) nanorice was designed and constructed by the liquid diffusion method. The introduction of iron metal nodes and the loading of Fe₂O₃ can effectively catalyze the Fenton reaction to produce hydroxyl radicals (^•OH) and overcome the hypoxic environment of tumor tissue by generating oxygen. The monodispersity and porosity of the porphyrin photosensitizers in the MOF structure exposed more active sites, which promoted energy exchange between porphyrin molecules and oxygen molecules for photodynamic therapy (PDT) treatment. Therefore, the generated hydroxyl radicals and singlet oxygen (¹O₂) can synergistically act on tumor cells to achieve the purpose of improving tumor therapy. Then the erythrocyte membrane was camouflaged to enhance blood circulation and tissue residence time in the body, and finally, the targeted molecule AS1411 aptamer was modified to achieve the high enrichment of MOF photosensitizers on a tumor domain. As a result, the MOF nanorice camouflaged by the erythrocyte membrane can effectively reduce side effects and improve the therapeutic effect of PDT and chemo-dynamic therapy (CDT). The study not only improved the efficacy of PDT and CDT in essence from the MOF nanorice but also used the camouflage method to further concentrate FeTCPP/Fe₂O₃ on the tumor sites, achieving the goal of multiple gains. These results will provide theoretical and practical directions for the development of tumor-targeted MOF nanomaterials.