Core-Shell Photosensitizer-Fenton Heterostructure Boosts Tumor Inhibition for Synergistic Therapy.

In this paper, a novel photosensitizer@Fenton reagent core-shell heterostructure is fabricated via a multiple self-assembly process, which exhibits a significant inhibitory effect on 4T1 cells (inhibition rate of 86.79%). Natural glucose oxidase (Gox) modified hollow mesoporous nano-manganese dioxide (H-MnO2@Gox) is used as a bio-recycling reactor, while the photosensitizer IR780 infiltrated into the interior of H-MnO2 through the pores and mesoporous dopamine (MPDA) coated on the surface of H-MnO2 are both act as photothermal reagents. Then, iron phosphate particles (FePi) are introduced as efficient Fenton reagents to form a H-MnO2@Gox/IR780@MPDA@FePi heterostructure. The heat generated by external light irradiation can be utilized to accelerate Fenton catalysis. In addition, under the assistance of dopamine, the formation of Fe(II) can be accelerated to guarantee the supply of enough Fe(II), which will react with H2O2 to produce highly toxic hydroxyl radicals (·OH). Subsequently, the in vitro cytotoxicity test indicated that the H-MnO2@Gox/IR780@MPDA@FePi heterostructure could exert a significant inhibitory effect on 4T1 cells (13.21%), yet had a minimal impact on HL-7702 cells, under the irradiation of near infrared (NIR) nanoplatform. This multimodal nanoplatform integrates oxygen generation, starvation therapy, photothermal therapy, and chemodynamic therapy, which is highly beneficial for improving the curative effect on tumors.