Multifunctional hemoporfin-Cu9S8-MnO2 for magnetic resonance imaging-guided catalytically-assisted photothermal-sonodynamic therapies

Integrated theranostic nanoplatforms with multi-model imaging and therapeutic functions are attracting great attention in cancer treatments, while the design and preparation of such nanoplatforms remain an open challenge. Herein, we report hemoporfin@Cu9S8@MnO2 nanoparticles (H@Cu9S8@MnO2 NPs) as multifunctional nanoplatforms for magnetic resonance imaging-guided catalytically-assisted photothermal-sonodynamic therapies of tumors. Cu9S8 hollow spherical nanoparticles were firstly prepared by in-situ vulcanization of Cu2O, and the growth of MnO2 shell was realized by the reduction of manganese permanganate, where the hollow structure of Cu9S8 could be used to load hemoporfin sonosensitizer. Cu9S8@MnO2 nanoparticles with diameters of ∼ 130 nm exhibit increased photoabsorption in near-infrared (NIR) region (680-1100 nm) due to the plasmonic effect of Cu9S8, and the photothermal conversion efficiency is determined to be 32.5% under 1064 nm laser irradiation. Furthermore, MnO2 shells can mimic catalase to trigger the decomposition of endogenous H2O2 into O2 with a significant O2 elevation (14.7 mg L-1) within 8 min and then promote the production of 1O2 via sonodynamic effect of hemoporfin. Meanwhile, MnO2 shells provide the T1-weight magnetic resonance (MR) imaging function. When H@Cu9S8@MnO2 NPs solution is administered to the mice, the tumor growth can be effectively inhibited due to catalytically-assisted synergetic photothermal-sonodynamic therapies which have superior therapeutic effect compared to mono-model therapy alone. Thus, H@Cu9S8@MnO2 NPs present a promising strategy for the development of integrated theranostic nanoplatforms with multi-model imaging and therapy functions.