Structure-oriented catalytic radiosensitization for cancer radiotherapy

Given that the outcome of clinical radiotherapy (RT) is closely related to the radiolysis products from the interactions between the radiation and intracellular water, an appropriate catalyst to promote radiolysis may improve the therapeutic efficacy. However, catalysis-based radiosensitization strategy remains under investigated. Herein, we propose a catalytic RT concept and synthesize Janus-like Au-Fe₂C nanoparticles (AFCNPs) as the catalytic radiosensitizer to improve the conversion efficiency of free radicals from the water molecules, resulting in a nearly five-fold increase in hydroxyl radicals (^[rad]OH) with comparison to pure Au nanoparticles under the clinical radiation dose. The theoretical simulation reveals that the catalytic activity of AFCNPs derived from the increase in the electron concentration on the surface of Au, as a result of the electron transfer from the Fe₂C moiety with lower work function to the Au moiety with higher work function. As a novel radiosensitization strategy, catalytic RT has shown promising potentials warranting further exploration.