Ratiometric fluorescent probe with AIE characteristics for hypochlorite detection and biological imaging.

It is very important and highly valuable to detect ClO in samples and living cells with accuracy and speed. In this work, a novel fluorescent probe NA was prepared from 4-bromo-1,8-naphthalic anhydride by acylation reaction and Suzuki coupling reaction and used for the detection of ClO. Thiomethyl serves as the recognition group for probe NA, while naphthalimide serves as fluorescent chromophore. The probe exhibited an extremely pronounced blue shift from yellow to blue fluorescence within 1 min after the addition of hypochlorite (ClO). The probe demonstrates high sensitivity to ClO with a limit of detection (LOD) of 1.22 µM. Also, probe NA demonstrates excellent selectivity and immunity to interference. Additionally, simple fluorescent test strips containing probe NA were prepared in this study, enabling rapid detection of ClO in water samples. And NA had been effectively used to image endogenous and exogenous ClOfluorescence in living cells. The results suggest that probe NA has significant potential for portable detection and biological applications.