Activatable Singlet Oxygen Generation from Lipid Hydroperoxide Nanoparticles for Cancer Therapy.

Reactive oxygen species (ROS)-induced apoptosis is a widely practiced strategy for cancer therapy. Although photodynamic therapy (PDT) takes advantage of the spatial-temporal control of ROS generation, the meticulous participation of light, photosensitizer, and oxygen greatly hinders the broad application of PDT as a first-line cancer treatment option. An activatable system has been developed that enables tumor-specific singlet oxygen (1 O2 ) generation for cancer therapy, based on a Fenton-like reaction between linoleic acid hydroperoxide (LAHP) tethered on iron oxide nanoparticles (IO NPs) and the released iron(II) ions from IO NPs under acidic-pH condition. The IO-LAHP NPs are able to induce efficient apoptotic cancer cell death both in vitro and in vivo through tumor-specific 1 O2 generation and subsequent ROS mediated mechanism. This study demonstrates the effectiveness of modulating biochemical reactions as a ROS source to exert cancer death.