A ratiometric benzothiazole-based fluorescence probe for selectively recognizing HClO and its practical applications

A ratiometric probe (HBT-HBZ) bearing 2-hydrazino benzothiazole and 3-(benzo[d]thiazol-2-yl)-2-hydroxy-5-methylbenzaldehyde for sensing HClO with high selectivity and sensitivity is reported in this article. The fluorescence intensity ratios (I_{470 nm}/I_{572 nm}) of the probe with different concentrations of analyte showed excellent selectivity and a linear response to minor changes in HClO. The detection limit of 24 nmol/L suggests that the sensor is very sensitive to HClO. According to the series of performed experiments, HBT-HBZ has practical applications, such as the detection of HClO residues in tap water, which has been rarely reported. In addition, confocal laser microscopy experiments confirmed that HBT-HBZ can selectively recognize HClO in HeLa cells. A ratiometric probe (HBT-HBZ) for sensing hypochlorous acid (HClO) with high selectivity and sensitivity is reported in this article. The probe exhibited high selectivity for HClO among other ROS, RNS and anions. In addition, HBT-HBZ has some practical applications such as the analysis of the HClO content in tap water. Furthermore, confocal fluorescence microscopy imaging showed that HBT-HBZ can be applied for detecting HClO in living cells.