Fenton-like reaction and glutathione depletion by chiral manganese dioxide nanoparticles for enhanced chemodynamic therapy and chemotherapy.

Chirality-based nanomaterials, especially semiconductors nanoparticles (NPs), are the emerging research in biomedicine field. Herein, chiral manganese dioxide (L/D-MnO) NPs were synthesized by using threonine molecules as chiral ligands. Then cisplatin loaded L/D-MnO (L/D-MnO@Pt) NPs were successfully constructed based on the high specific surface area of L/D-MnO NPs. L/D-MnO@Pt NPs could be specifically internalized by tumor cells and efficiently deplete the glutathione (GSH) through redox reaction to release Mn and Pt. The released Mn exhibited strong chemodynamic effect through Fenton-like reaction. The depletion of GSH further improved the chemodynamic therapy (CDT) efficiency. The combination of the CDT of Mn with the chemotherapy of Pt considerably enhanced the tumor therapy efficiency. It was particularly noteworthy that L/D-MnO@Pt NPs showed chirality-based different internalization by tumor cells and further led to different tumor cell ablation effects, in which D-MnO@Pt NPs exhibited stronger therapeutic efficiency than L-MnO@Pt NPs. These findings provided deep insights for novel biomedical applications of chirality-based semiconductors NPs.