Custom-Made Piezoelectric Solid Solution Material for Cancer Therapy.

Piezoelectric material-mediated sonodynamic therapy (SDT) has received considerable research interest in cancer therapy. However, the simple applications of conventional piezoelectric materials do not realize the full potential of piezoelectric materials in medicine. Therefore, the energy band structure of a piezoelectric material is modulated in this study to meet the actual requirement for cancer treatment. Herein, an elaborate PEGylated piezoelectric solid solution 0.7BiFeO 3 -0.3BaTiO 3 nanoparticles (P-BF-BT NPs) is synthesized, and the resultant particles achieve excellent piezoelectric properties and their band structure is tuned via band engineering. The tuned band structure of P-BF-BT NPs is energetically favorable for the synchronous production of superoxide radicals (•O 2 - ) and oxygen (O 2 ) self-supply via water splitting by the piezoelectric effect. Besides, the P-BF-BT NPs can initiate the Fenton reaction to generate hydroxyl radical (•OH), and thus, chemodynamic therapy (CDT) can be augmented by ultrasound. Detailed in vitro and in vivo research has verified the promising effects of multimodal imaging-guided P-BF-BT NP-mediated synergistic SDT/CDT by the piezo-Fenton process in hypoxic tumor elimination, accompanied by high therapeutic biosafety. The current demonstrates a novel strategy for designing and synthesizing "custom-made" piezoelectric materials for cancer therapy in the future.