Minimalist O2 generator formed by in situ KMnO4 oxidation for tumor cascade therapy

Diverse oxygen generation strategies have been developed to overcome hypoxia in tumors for enhancing the therapeutic efficacy, but inevitably suffering from tedious synthesis process of oxygen generators in vitro before in vivo administration. Herein, we show direct injection of commercially and clinically used KMnO 4 into solid tumors enables in situ formation of MnO 2 as an oxygen depot for cascade oxidation damage and enhanced photodynamic therapy. KMnO 4 can damage tumor tissues by oxidation and generate MnO 2 , and subsequent intravenous injection of Ce6 allows MnO 2 -triggered hypoxia-modulated photodynamic therapy of tumors. Excellent cascade tumor suppression effect is realized both in vitro and in vivo based on the KMnO 4 –Ce6 system without the need of synthesis. The proposed strategy lays down a novel way with unprecedented superiors of no need of synthesis process and ultra-facile administration procedure for tumor hypoxia-modulated cascade therapy.