A fluorescent sensor for fast detection of peroxynitrite by removing of C=N in a benzothiazole derivative

A simple structured reaction-based probe for peroxynitrite (ONOO−) was developed by using benzothiazole hydrazone base of the excited-state intramolecular proton transfer (ESIPT) dye. It was constructed from 2-hydrazinylpyridine and 3-(benzo[d]thiazol-2-yl)-2-hydroxy-5-methylbenzaldehyde which possesses itself weak fluorescence and displayed prominent fluorescence response towards ONOO− by oxidizes the C=N bond to an aldehyde in aqueous solution. The probe exhibited excellent selectivity and high sensivity towards ONOO− with a low dectection limit of 5.8 × 10−8 M in physiological condition. Moreover, the probe could realize fast recognition to ONOO− in as short as 60 s. In addition, the probe was also successfully used for living cell imaging.