H 2 O 2 -independent chemodynamic therapy initiated from magnetic iron carbide nanoparticle-assisted artemisinin synergy.

Chemodynamic therapy (CDT) is a booming technology that utilizes Fenton reagents to kill tumor cells by transforming intracellular H ₂ O ₂ into reactive oxygen species (ROS), but insufficient endogenous H ₂ O ₂ makes it difficult to attain satisfactory antitumor results. In this article, a H ₂ O ₂ -free CDT technique with tumor-specificity is developed by using pH-sensitive magnetic iron carbide nanoparticles (PEG/Fe ₂ C@Fe ₃ O ₄ NPs) to trigger artemisinin (ART) to in situ form ROS. ART-loaded PEG/Fe ₂ C@Fe ₃ O ₄ NPs are fabricated for the enormous release of Fe ²⁺ ions induced by the acidic conditions of the tumor microenvironment after magnetic-assisted tumor enrichment, which results in the rapid degradation of the PEG/Fe ₂ C@Fe ₃ O ₄ NPs and release of ART once endocytosed into tumor cells. In situ catalysis reaction between the co-released Fe ²⁺ ions and ART generates toxic ROS and then induces apoptosis of tumor cells. Both in vitro and in vivo experiments demonstrate that the efficient Fe-enhanced and tumor-specific CDT efficacy for effective tumor inhibition based on ROS generation. This work provides a new direction to improve CDT efficacy based on H ₂ O ₂ -independent ROS generation.
Competing Interests: There are no conflicts to declare.
(This journal is © The Royal Society of Chemistry.)