Oxygen and Indocyanine Green loaded microparticles for dual-mode imaging and sonodynamic treatment of cancer cells.

Oxygen and Indocyanine Green (ICG) loaded microparticles (OI-MPs) were fabricated by a gas-driven coaxial flow focusing (CFF) process for dual-mode imaging and sonodynamic therapy (SDT). The produced OI-MPs agent showed stable optical properties, superior imaging depth in near infrared (NIR) fluorescence imaging, and enhanced acoustic contrast after ultrasound mediation. We hypothesized that encapsulating ICG and oxygen in microparticles would enhance reactive oxygen species (ROS) production in SDT. This hypothesis was validated in a cell-free environment. We further hypothesized that ultrasound mediated fragmentation of the OI-MPs would induce cytotoxicity and apoptosis of cancer cells. This hypothesis was validated in SKOV3 ovarian cancer cells. Our research demonstrated that OI-MPs can be potentially used as a dual-mode theranostic agent for image guided SDT with enhanced efficacy. Further study is needed to delineate the mechanism of ROS-induced cell apoptosis and optimize the OI-MPs formulation for the maximal anti-cancer potency.