A Reversible Fluorescent Probe for In Situ Monitoring Redox Imbalance during Mitophagy.

Mitophagy is the lysosome-dependent degradation of damaged and dysfunctional mitochondria, which is closely associated with HO-related redox imbalance and pathological processes. However, development of fast-responding and highly sensitive reversible fluorescent probes for monitoring of mitochondrial HO dynamics is still lacking. Herein, we report a reversible fluorescent probe () that enables real-time imaging of HO-related redox imbalance. In vitro studies demonstrated that had a rapid response and high sensitivity to the HO/GSH redox cycle, with a detection limit of 17 nM for HO. was applied to imaging of HO fluctuation in living cells with excellent reversibility and mitochondrial targeting. reveals an increase in mitochondrial HO under lipopolysaccharide stimulation and a decrease in HO following the combined treatment with rapamycin. This suggests that the level of oxidative stress is significantly suppressed after the enhancement of mitophagy. The rationally designed offers a powerful tool for understanding redox imbalance during mitophagy.