One-for-AII-Type, Biodegradable Prussian Blue/Manganese Dioxide Hybrid Nanocrystal for Trimodal Imaging-Guided Photothermal Therapy and Oxygen Regulation of Breast Cancer

Multiinodal imaging-guided diagnosis arid therapy has been highlighted in the area of theranostic nanomaterials. To proivide more suitable theranostic candidates,. Prussian blue (PB)/manganesedioxide (MiO(2))hybrid nanoparticles (PBMn) smaller than 50 nm are prepared by a one-pot method. MnO2, which is reduced from KMnO4:, not only controls the particle size, the optical properties, and the transverse relaxation rate (r(2)) = of PB but also enhances the catalysis efficacy of,PB to H2O2 for oxygen generation. PBMn can serve as a photoacoustic imaging (PAI) and longitudinal relaxation (T-1) mode magnetic resonance imaging contrast agent (14 times and 1.8 times of the saline-treated group, respectively). Injection of PBMn can regulate the, oxygen partial pressure of the tumor tissue from 2.1 +/- 0.2 to 9.3 +/- 0.4 kPa and rearrange the ratio: of oxygenated hemoglobin and deoxygenate hemoglobin:inside the tumor, which favor the enhancement of the diamagnetic T-2-weighted imaging (T2WI) signal intensity (two times that of the saline-treated group). Furthermore, PBMn-mediated PTT can efficiently inhibit the growth of the MCF-7 tumor in vitro and in vivo. PBMn can serve as a PAI/T-1/T-2 trimodal contrast agent and in imaging-guided PTT, as well as in the oxygen regulation of the exografted breast cancer.