A GSH-activated photosensitizer prodrug for fluorescence imaging-guided chemo-photodynamic therapy

To improve the treatment efficacy of chemotherapy and reduce its side effects, combination therapy has gained increasing recognition. Nonetheless, it also faces with challenges including off-target effects and damage to normal cells. Herein, we designed a GSH-activated photosensitizer prodrug (NBSCEA) for fluorescence imaging and selective tumor elimination. Firstly, NBSCEA is encapsulated in DSPE-PEG2000 micelles to form NBSCEA@D nanoparticles for prodrug delivery. Then, the overexpressed GSH in tumor microenvironment can destroy the disulfide bonds of NBSCEA, and release nitrogen mustard and NBS-NH. Furthermore, upon exposure to 660 nm light, NBS-NH will produce Reactive oxygen species (ROS) that combine with chemotherapy to eradicate tumor cells. In vivo studies show that NBSCEA@D can not only be used for tumor imaging, but also effectively inhibit tumor growth through synergistic treatment. Our work demonstrates a highly efficient fluorescence imaging-accurate treatment strategy of cancer.