Enhancing Tumor Catalytic Therapy by Co-Catalysis

Fenton reactions have been recently applied in tumor catalytic therapy, whose efficacy suffers from the unsatisfactory reaction kinetics of Fe³⁺ to Fe²⁺ conversion. Here we introduce a co-catalytic concept in tumor catalytic therapy by using a two-dimensional molybdenum disulfide (MoS₂) nanosheet atomically dispersed with Fe species. The single-atom Fe species act as active sites for triggering Fenton reactions, while the abundant sulfur vacancies generated on the nanosheet favor electron capture by hydrogen peroxide for promoting hydroxyl radical production. Moreover, the 2D MoS₂ support also acts as a co-catalyst to accelerate the conversion of Fe³⁺ to Fe²⁺ by the oxidation of active Mo⁴⁺ sites to Mo⁶⁺, thereby promoting the whole catalytic process. The 2D nanocatalyst exhibits a desirable catalytic performance, as well as a significantly enhanced anticancer efficacy both in vitro and in vivo, which indicates the feasibility for applying such a co-catalytic concept in tumor therapy.