Recyclable Endogenous H<sub>2</sub>S Activation of Self‐Assembled Nanoprobe with Controllable Biodegradation for Synergistically Enhanced Colon Cancer‐Specific Therapy
Junqing Huang, Zhiming Deng, Shenghui Bi, Xingwang Wen, Songjun Zeng
Abstract
Abstract Excessive production of hydrogen sulfide (H 2 S) plays a crucial role in the progress of colon cancer. Construction of tumor‐specific H 2 S‐activated smart nanoplatform with controllable biodegradation is of great significance for precise and sustainable treatment of colon cancer. Herein, an endogenous H 2 S triggered Co‐doped polyoxometalate (POM‐Co) cluster with self‐adjustable size, controlled biodegradation, and sustainable cyclic depletion of H 2 S/glutathione (GSH) is designed for synergistic enhanced tumor‐specific photothermal and chemodynamic therapy. The designed POM‐Co nanocluster holds H 2 S responsive “turn‐on” photothermal property in colon cancer via self‐assembling to form large‐sized POM‐CoS, enhancing the accumulation at tumor sites. Furthermore, the formed POM‐CoS can gradually biodegrade, resulting in release of Co 2+ and Mo 6+ for Co(II)‐catalyzed •OH production and Russell mechanism‐enabled 1 O 2 generation with GSH consumption, respectively. More importantly, the degraded POM‐CoS is reactivated by endogenous H 2 S for recyclable and sustainable consumption of H 2 S and GSH, resulting in tumor‐specific photothermal/chemodynamic continuous therapy. Therefore, this study provides an opportunity of designing tumor microenvironment‐driven nanoprobes with controllable biodegradation for precise and sustainable anti‐tumor therapy.