Intracellular Imaging of Glutathione with MnO 2 Nanosheet@Ru(bpy) 3 2+ -UiO-66 Nanocomposites.

Fluorescent detection of Glutathione (GSH) in living being system has attracted much attention, but currently most fluorescent probes were usually exposed to the exterior environment, leading to the photo-bleaching and premature leakage, and subsequently limiting the sensitivity and photostability. Herein, luminescent metal organic frameworks (MOFs) (Ru(bpy)32+ encapsulated UiO-66) coated with manganese dioxides nanosheets (MnO2 NS@Ru(bpy)32+-UiO-66) by in-situ growth method were explored for the fabrication of GSH switched fluorescent sensing platform. In the proposed platform, the coated Manganese dioxides nanosheets(MnO2 NS) and encapsulated UiO-66 could effectively prohibit the leakage of loaded Ru(bpy)32+. Because of the splendid fluorescence quenching ability, special probe leakage blocking role and distinguished redox activity to recognize GSH of MnO2 NS, and the improved fluorescence of Ru(bpy)32+ by UiO-66, the low background, highly sensitive and selective detection of GSH with a low limit of detection (LOD) as 0.28 μM was realized. At the same time, the preparation of MnO2 NS@Ru(bpy)32+-UiO-66 nanocomposites is simple, low toxic and there was no notable loss of cell survivability after being exposed to the MnO2 NS@Ru(bpy)32+-UiO-66 below the concentrations of 120 μg mL-1 for 24 h. So that the results coming from this effort suggest that the new sensor will have a great potential to apply for detection of GSH in living cells.