Piezoelectric materials for synergistic piezo- and radio-catalytic tumor therapy

Radio-catalytic therapy (RCT) is emerging as a split-new sensitization modality for photon radiotherapy. However, the outcome of RCT is greatly hurdled by the insufficient intracellular catalytic substrates such as H2O2. Here we provided a synergistic oncotherapy strategy that utilized BiOCl-based piezoelectric nanocatalysts to successively mediate medical ultrasound and X-rays for piezo- and radio-catalytic tumor suppression. First, BiOCl-based nanocatalysts were able to mediate piezo-catalysis under ultrasound excitation to achieve wireless in-situ supply of H2O2. Subsequently, due to the role of the electronic sacrificial agent of H2O2, radio-catalytic hydroxyl radical generation of BiOCl-based nanocatalysts upon X-ray irradiation was significantly accelerated. The elevated free radicals via synergistic dual-catalysis could cause serious damage to tumor cells. Furthermore, such a synergistic effect in vivo of piezo- and radio-catalysis inducing a maximized tumor suppression was also confirmed. Together, this work provided a potent strategy of the in-situ intratumoral H2O2 supply for boosting radio-catalytic cancer therapy, simultaneously broadening the scope of piezoelectric materials in biomedical application.