Defect-rich platinum-zinc oxide heterojunction as a potent ROS amplifier for synergistic sono-catalytic therapy

Sonodynamic therapy (SDT) is a physical therapy that utilizes critical sonosensitizers triggered by ultrasound to achieve an effective non-invasive tumor treatment. However, the inadequate sonodynamic efficacy and low responsive activities of traditional inorganic sonosensitizers have hindered its practical application. Here, we rationally design a platinum-zinc oxide (Pt -ZnO) sonosensitizer to significantly enhance the efficacy of SDT through its inherent bandgap structure and dual-nanozyme activities. The Pt -ZnO possesses a narrow bandgap (2.89 eV) and an appropriate amount of oxygen defects, which promote the efficiency of electrons and holes separation and the generation of reactive oxygen species (ROS) under US irradiation. Simultaneously, the Pt -ZnO exhibits both catalase-like and peroxidase-like activities, which effectively catalyze endogenous H 2 O 2 into a large number of O 2 and toxic hydroxyl radicals ( center dot OH), thus achieving an efficient enhancement of SDT and catalytic therapy. Moreover, the Pt -ZnO has significant glutathione consumption performance, further amplifying the oxidative stress. Ultimately, the Pt -ZnO achieves a triple ROS amplification effect, with the yields of singlet oxygen ( 1 O 2 ) and center dot OH reaching 859.1 % and 614.4 %, respectively, inducing a highly effective sono-catalytic therapy with a remarkable tumor inhibition rate of 98.1 %. This study expands the application of ZnO semiconductor heterojunctions in the nanomedicine area, and the simple yet efficient design of the Pt -ZnO provides a strategy for the development of sonosensitizers.

Automated summary

Sonodynamic therapy (SDT) is a new method for tumor treatment that utilizes sonosensitizers triggered by ultrasound. In this study, researchers designed a platinum-zinc oxide (Pt -ZnO) sonosensitizer to enhance the efficacy of SDT. Pt -ZnO possesses a narrow bandgap and dual-nanozyme activities, promoting the generation of reactive oxygen species (ROS) and enhancing SDT. Additionally, Pt -ZnO exhibits catalase-like and glutathione consumption performance, amplifying the therapeutic effect of SDT. This study demonstrates the potential of Pt -ZnO in tumor treatment.