Real time precisely tracing the fluctuations of mitochondrial SO 2 in cells during ferroptosis and tissues using a mitochondrial-immobilized ratiometric fluorescent probe.

Mitochondrial sulfur dioxide (SO ₂ ) plays important roles in physiological and pathological activities. Unfortunately, it is lack of a reliable tool to precisely visualize the mitochondrial SO ₂ and elaborate its complicated functions in various cytoactivities. Here we report a mitochondrial-immobilized fluorescent probe PM-Cl consisting of coumarin and benzyl chloride modified benzothiazole, which enables selective visualization of mitochondrial SO ₂ via chemical immobilization. The spectral results demonstrated that probe PM-Cl could respond to SO ₂ with high selectivity and sensitivity. Co-localization and the fluorescence of cytolysis extraction verified the excellent mitochondrial targeting and anchoring abilities. Due to the chemical immobilization, probe PM-Cl could firmly retain into mitochondria after stimulation of carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and H ₂ O ₂ . Significantly, a series of fluorescence images are indicative of capability for detecting the fluctuations of SO ₂ in mitochondria during ferroptosis. Furthermore, PM-Cl also could visualize SO ₂ in myocardium and muscle tissues after the stimulation of CCCP. Taken together, probe PM-Cl is a very potential molecular tool for precisely detecting mitochondrial SO ₂ to explore its complex functions in physiological and pathological activities.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier B.V.)