A piezoelectric nanoplatform for ultrasound-triggered ROS storm via synergistic piezo-catalytic and fenton reactions to eradicate bladder tumors

Sonodynamic therapy (SDT) is considered an effective method for treating bladder cancer, but the limited electron transfer of a single material and the hypoxic microenvironment of cancer limit the efficiency of SDT. Here, barium titanate (BTO) was prepared, and Cu was doped into BTO through hydrothermal synthesis and high-temperature annealing, followed by surface conjugation of tumor-specific proteins (BTO/Cu/PDA/Nectin-4). The Cu doping enhances the ferroelectric polarization of BTO and reduces its bandgap, facilitating electron transfer. Meanwhile, Cu can react with hydrogen peroxide (H₂O₂) via the Fenton reaction to generate reactive oxygen species (ROS), thereby enhancing the chemodynamic therapy (CDT) effect. The combination of SDT and CDT enhanced ROS production, and both in vitro and in vivo results demonstrated excellent cytotoxic effects and tumor suppression against bladder cancer cells. This combined SDT and CDT approach offers an effective therapeutic strategy for antitumor treatment.