P–N Type ReS₂/Cu₂O Nanoheterojunction for Sonodynamic and Chemodynamic Tumor Therapy

In recent years, chemodynamic therapy (CDT) and sonodynamic therapy (SDT) have garnered significant attention as noninvasive approaches in the field of tumor treatment. However, the unique characteristics of the tumor microenvironment, such as hypoxia and high antioxidant capacity, limit the therapeutic efficacy of single-modality treatments. In this study, we constructed a binary heterojunction sonosensitizer (ReS2/Cu2O, RC) by combining n-type semiconductor ReS2 with p-type semiconductor Cu2O through a simple physical stirring method, aiming to achieve synergistic sonodynamic and chemodynamic tumor therapy. First, we systematically characterized the physicochemical properties of ReS2, Cu2O, and RC, and investigated the mechanisms of reactive oxygen species (ROS) generation in RC heterojunctions. Experimental results demonstrated that under ultrasound excitation, ReS2 could convert oxygen into •O2–, which was subsequently transformed into 1O2 by Cu2O. Simultaneously, the Cu+ in Cu2O catalyzed the conversion of H2O2 into •OH via the Fenton reaction. Both in vitro cell experiments and in vivo tumor models revealed that the synergistic therapeutic effect of RC significantly outperformed that of standalone SDT or CDT. This study achieved synergistic CDT and SDT through the rational design of nano heterojunctions, providing a research direction and methodological foundation for tumor therapy.