A ratiometric fluorescent probe for reversible monitoring of endogenous SO2/formaldehyde in cytoplasm and nucleoli regions and its applications in living mice

Abstract

The excessive production of sulfur dioxide (SO₂) and formaldehyde (FA) by organisms is closely associated with several diseases, including neurological disorders, respiratory disease, and genotoxicity. RNA plays a central role in the expression of genes. However, it is difficult for fluorescent probes to explore the intersecting correlation of SO₂ and FA near the nucleolus regions due to the protective obstacle of the cell nucleus membrane. Herein, a unique fluorescent probe (DP) for reversible detection of the interaction of SO₂ and FA in the nucleolus regions was constructed. In light of the outstanding attributes of DP, including a large fluorescence ratio variation, ultrafast detection of SO₂, and excellent reversibility, it was successfully employed to track the variation of endogenous SO₂ and FA in the cytoplasm and nucleolus regions of live cells. In addition, the DP probe could be applied to the imaging of endogenous SO₂ and then recovered by FA in live mice.