Ultrasound-Triggered Piezocatalytic Cancer Therapy Using Piezoelectric Nanomaterials

Piezoelectric nanomaterials, which are capable of generating reactive oxygen species (ROS) via piezocatalytic redox reactions under mechanical stress have emerged as promising nanoplatforms for efficient cancer treatment. Herein, piezoelectric nanoparticles such as ZnO nanorods and metal sulfide nanoparticles were functionalized with poly(ethylene glycol) (PEG) and loaded with chemodrugs for ultrasound (US)-triggered combination chemo-piezocatalytic cancer therapy. The drug-loaded piezoelectric nanoparticles can efficiently induce piezoelectric polarization for the generation of ROS under US irradiation. In addition, the drug-loaded piezoelectric nanoparticles not only generated ROS under US irradiation but also improved the intracellular delivery of chemodrugs. In vivo study showed that drug-loaded piezoelectric nanoparticles effectively accumulated in the tumors and significantly suppressed the tumor growth under US irradiation without systemic toxicity. This study demonstrates the feasibility of piezoelectric nanoparticles as US-triggered piezocatalytic agents that can selectively and effectively eradicate tumors via chemo-piezocatalytic combination therapy.