Hydrogen Peroxide-Activatable Nanoparticles for Luminescence Imaging and Triggerable Photodynamic Therapy of Cancer

Abnormally increased reactive oxygen species (ROS) are intimately related to the development and metastasis of cancer. Since hydrogen peroxide (HO) is a major component of ROS, molecular imaging and selective treatment in response to high HO are intriguing for the management of cancers. Herein, we report novel self-assembly luminescent nanoparticles, which can be activated by HO, thereby serving as an effective nanotheranostics for luminescence imaging and photodynamic therapy (PDT) of tumors with high HO. This functional nanomedicine was assembled from an amphiphilic conjugate (defined as CLP) based on chlorin e6 (Ce6) simultaneously conjugated with luminol and poly(ethylene glycol), exhibiting a well-defined core-shell nanostructure. Upon triggering by pathologically relevant levels of HO, CLP nanoparticles produced luminescence due to the luminol unit and simultaneous excitation of Ce6 by chemiluminescence resonance energy transfer, enabling and imaging of tumors with highly expressed HO. In addition, excited Ce6 can produce singlet oxygen (O) for PDT of HO-high tumors and inhibiting lung metastasis, which was demonstrated by and experiments. Furthermore, preliminary studies revealed the biosafety of CLP nanoparticles. Consequently, the self-illuminating nanoparticles are promising for noninvasive imaging and therapy of tumors with high expression of HO.