The water-soluble bicyclic 2-pyridone-based fluorescent probe for fast and selective detection of hypochlorite

As a strong oxidizer, hypochlorite (ClO–) are widely employed as bleaching agents and disinfectants. Determination of ClO– is required to ensure bactericidal effects and avoid hazards caused by excessive residual chlorine. Herein, the derivative bicyclic 2-pyridone, namely DHIP-Py, was prepared successfully to establish a new ClO–-quantitative method. The probe exhibits excellent ClO– selectivity over other ROS and anions/cations, high sensitivity (LOD = 1.32 µmol/L), fast response (<5 s), and wide-pH tolerance (pH 4∼10). Benefit from its good water solubility, DHIP-Py is well suited for water sample analysis and has been successfully applied to detect ClO– in real-world food and environmental samples, including tap water, bottled water and river water. The detection results were essentially identical to that of obtained from traditional DPD method. Moreover, visual detection of ClO– via filter paper-based solid sensor and imaging of ClO– in Escherichia coli were also achieved by DHIP-Py. These satisfactory results demonstrate that this bicyclic 2-pyridone-based hypochlorite probe is a promising free chlorine chemosensor with great potential for analytical applications.