Singlet Oxygen Generation in Dark‐Hypoxia by Catalytic Microenvironment‐Tailored Nanoreactors for NIR‐II Fluorescence‐Monitored Chemodynamic Therapy
Tao Chen, Peidong Hou, Yafei Zhang, Rujiang Ao, Lichao Su, Yifan Jiang, Yuanli Zhang, Huilan Cai, Jun Wang, Qiushui Chen, Jibin Song, Lisen Lin, Huanghao Yang, Xiaoyuan Chen
Abstract
Abstract Singlet oxygen ( 1 O 2 ) has a potent anticancer effect, but photosensitized generation of 1 O 2 is inhibited by tumor hypoxia and limited light penetration depth. Despite the potential of chemodynamic therapy (CDT) to circumvent these issues by exploration of 1 O 2 ‐producing catalysts, engineering efficient CDT agents is still a formidable challenge since most catalysts require specific pH to function and become inactivated upon chelation by glutathione (GSH). Herein, we present a catalytic microenvironment‐tailored nanoreactor (CMTN), constructed by encapsulating MoO 4 2− catalyst and alkaline sodium carbonate within liposomes, which offers a favorable pH condition for MoO 4 2− ‐catalyzed generation of 1 O 2 from H 2 O 2 and protects MoO 4 2− from GSH chelation owing to the impermeability of liposomal lipid membrane to ions and GSH. H 2 O 2 and 1 O 2 can freely cross the liposomal membrane, allowing CMTN with a built‐in NIR‐II ratiometric fluorescent 1 O 2 sensor to achieve monitored tumor CDT.