Bifunctional Single-Molecular Fluorescent Probe: Visual Detection of Mitochondrial SO and Membrane Potential.

Mitochondrial membrane potential (MMP) and sulfur dioxide (SO) significantly affect the mitochondrial state. In this work, and were constructed through side-chain engineering, in which bearing the poorer hydrophobicity could localize on mitochondria better. Interestingly, short-wave emission was captured due to the sensitive response of to SO (LOD = 13.8 nM). Meanwhile, the probe could bind with DNA, presenting enhanced long-wave emission. Encouragingly, could migrate from mitochondria to the nucleus when MMP was decreased, accompanied by the increase of fluorescence lifetime (9-fold). Hence, could be used for dual-channel monitoring of mitochondrial SO and MMP, which showed a completely different pathway from the commercial MMP detectors JC-1/JC-10. The cellular experiments showed that MMP was gradually decreased due to reactive oxygen species-triggered oxidative stress, and the SO level was up-regulated simultaneously. Overall, this work proposed a new method to investigate and diagnose the mitochondrial-related diseases.