A fast-response, highly specific fluorescent probe for the detection of picomolar hypochlorous acid and its bioimaging applications

摘要

Highly specific and ultrasensitive fluorescent probes for tracking the intracellular native hypochlorous acid (HOCl) levels are urgently needed owing to its important molecular functions in the biological systems. In this contribution, a simple thiocarbamate-caged 7-hydroxycoumarin (TCHC) was developed as fluorescent probe for monitoring HOCl in live cells. ProbeTCHCexhibited preeminent specificity towards HOCl over other various bioactive substances. Importantly, probeTCHCcould sensitively detect HOCl in the range of 0–175 pM with the detection limit of 17 pM, which was attributed to the multiple fluorescence sensing mechanisms including photo-induced electron transfer (PET), intramolecular charge transfer (ICT), and the chlorination. Furthermore, probeTCHCdisplayed an instant response towards HOCl (<3 s), and thus the real-time detection of HOCl could be achieved. Finally, probeTCHCwas successfully applied to monitor native HOCl and the fluctuations of endogenous HOCl levels in live cells.