High Ultrasonic Current Density Hollow Nanorods Hijack Endogenous Iron for Accelerated Tumor Piezocatalytic Therapy.

Insufficient charge separation and sluggish carrier transport hinder the development of piezocatalytic therapy. To overcome these limitations, polyvinyl pyrrolidone-modified hollow amorphous ruthenium telluride (RTP) nanorods are ingeniously engineered, providing a stepwise countermeasure for the synergistic treatment of apoptosis and ferroptosis. Compared to traditional piezocatalytic sensitizers, RTP exhibits unique advantages: I) a high piezoelectric coefficient (d₃₃: 23.1 pmV^-1), II) overlapping energy bands (-0.20 eV), and III) significantly higher US current density (200.3 nA cm^-2). Importantly, this elevated US current density not only accelerates the conversion of endogenous iron (Fe³⁺/Fe²⁺), leading to iron overload, but also generates reactive oxygen species (ROS) storms, ultimately inducing oxidative stress and ferroptosis efficiently. This ingeniously designed nanoplatform, embodying "exogenous energy harvesting synergized with endogenous ion utilization," serves as a promising candidate for efficient piezoelectric nanomedicine.