Ultrasound-Induced Reactive Oxygen Species Mediated Therapy and Imaging Using a Fenton Reaction Activable Polymersome

TLDR

Ultrasound is widely used for diagnostics and is anticipated to enable simultaneous imaging and therapy due to its low cost, accessibility, and noninvasive real‑time imaging. This study reports a hydrogen peroxide–filled polymersome that provides echogenic reflectivity and ROS‑mediated cancer therapy triggered by diagnostic ultrasound and accompanied by MR imaging. The polymersome encapsulates H₂O₂ and Fe₃O₄ in a PLGA shell, releasing O₂ for echogenicity and generating hydroxyl radicals via a Fenton reaction when disrupted by ultrasound. The approach completely eradicated malignant tumors in a nonthermal process.

Abstract

Ultrasound techniques have been extensively employed for diagnostic purposes. Because of its features of low cost, easy access, and noninvasive real-time imaging, toward clinical practice it is highly anticipated to simply use diagnostic ultrasound to concurrently perform imaging and therapy. We report a H2O2-filled polymersome to display echogenic reflectivity and reactive oxygen species-mediated cancer therapy simply triggered by the microultrasound diagnostic system accompanied by MR imaging. Instead of filling common perfluorocarbons, the encapsulation of H2O2 in H2O2/Fe3O4–PLGA polymersome provides O2 as the echogenic source and •OH as the therapeutic element. On exposure to ultrasound, the polymersome can be easily disrupted to yield •OH through the Fenton reaction by reaction of H2O2 and Fe3O4. We showed that malignant tumors can be completely removed in a nonthermal process.