Near-infrared mitochondria-targeted fluorescent probe with a large Stokes shift for rapid and sensitive detection of cysteine/homocysteine and its bioimaging application

In this work, tetrahydro-acridine salt hybrid coumarin dyes was designed and developed as a Near-infrared (NIR) fluorescent probe CM for the detection and fluorescent bioimaging of Cys/Hcy. The activated chlorine atom in probe facilitates more efficient nucleophilic substitution reaction, resulting in fast responsive time (3 min toward 3 eq. Cys) and high sensitivity toward Cys with detection limit of 46 nM. More importantly, probe displays Turn -on near-infrared fluorescence emission (Emmax: 674 nm) with Large Strokes shift (about 200 nm) toward Cys/ Hcy. Furthermore, probe could be used as efficient tool for imaging and detection of Cys/Hcy in mitochondria of living cells and in vivo. This work innovatively proposed a new design strategy for NIR fluorescent probe platform for the detection and fluorescence imaging of bio-thiols.

Automated summary

In this study, a novel near-infrared fluorescent probe was designed and developed for the detection and fluorescence imaging of cysteine/homocysteine. The probe exhibited rapid response and high sensitivity, with a detection limit of 46 nM for cysteine. Additionally, the probe could be employed for imaging and detection in living cells and in vivo.