Reaction-based chemosensor as dual-channel indicator for visualizing and bioimaging of exogenous hypochlorite concentrations in living cells, Pseudomonas aeruginosa, and zebrafish.

Tracking and quantifying hypochlorite (ClO) in biological systems and environments remain challenging tasks, and many efforts have been made to improve ClO recognition performance by modifying the sensor structure. In this study, a pre-designed coumarin/furanohydrazide-based sensor (CMFH) with the coumarin moiety as the building block (fluorogen) was rationally prepared as a ratiometric and colorimetric chemosensor for ClO recognition. As expected, CMFH demonstrated excellent sensitivity and selectivity for ClO detection. The fluorescence signal ratio (F/F) showed strong ClO dependency, and the sensor exhibited ultrafast detection (within 60 s) and a low detection limit of 563 nM. Due to its low cytotoxicity and good tissue permeability, CMFH was demonstrated as a dual-channel sensor for ClO bioimaging and visualization in cells, zebrafish, and even bacteria. Furthermore, CMFH-loaded paper strips were successfully applied to the colorimetric and fluorescent visualization of ClO. The results demonstrate that CMFH has potential application value for tracking ClO in various biosystems and environments.