MnO2-Laden Black Phosphorus for MRI-Guided Synergistic PDT, PTT, and Chemotherapy

An elaborately designed multifunctional nanoplatform with intelligent and inherent tumor-specific theranostic capacity is urgently desired for highly efficient cancer treatments. Herein, we report a class of compact MnO2-laden black phosphorus (BPN/MnO2) nanostructure for delivering drugs with smart tumor-specific diagnosis and exquisite self-driven therapeutic features. The auxiliary MnO2 nanosheets promote the photodynamic therapy (PDT) of black phosphorus nanosheets (BPNs) by 3.8-fold through their inherent remarkable hypoxia amelioration. Moreover, BPN/MnO2 shows an obvious 37% photothermal therapy (PTT) enhancement relative to BPNs. Significantly, the multiple-tumor-microenvironment-responsive features of MnO2 contribute to the maximized drug administration on the tumor (≥4-fold drug release of the single acid stimuli), thus reducing the potential side effect of chemotherapy on normal tissues. Besides the spatiotemporally programmable administration of drugs, BPN/MnO2 also provides intelligent MRI and thermal imaging guidance for synergistically enhancing PDT, PTT, and chemotherapy, thus offering an intelligent versatile toolbox for multifunctional nanotheranostic applications.