Intratumoral Glutathione Activatable Nanoprobes for Fluorescence and 19F Magnetic Resonance Turn-On Imaging

Tumor microenvironment turn-on nanoprobes that could specifically detect the occurrence of diseases possess great potential in early diagnosis. Here, a GSH activated nanoprobe was designed for fluorescence and F-19 magnetic resonance (MR) dual-modal turn-on imaging of tumors. Specifically, fluorescence AgInS2 quantum dots (QDs for fluorescence imaging) were coencapsulated with perfluoro-15-crown-5-ether ((PFCE)-F-19 for19F MRI) by amphiphilic polymers and further coated with in situ formed manganese dioxide (MnO2) nanoshells, which served as efficient fluorescence and F-19 MR quenchers due to energy transfer and paramagnetic relaxation effects, respectively. The over-expressed GSH in tumors would decompose the MnO2 nanoshells, resulting in remarkable enhancement of both fluorescence and F-19 MRI signals of the nanoprobes, accordingly lighting up the tumor site.