Ratiometric Two-Photon Fluorescent Probe for Detecting and Imaging Hypochlorite.

The ratiometric fluorescent probe B6S, which contains pyrene as a fluorophore and imidazoline-2-thione as a reactive site, was developed for detection of hypochlorite (OCl). B6S displays a high specificity toward OCl in contrast to other reactive oxygen species and reactive nitrogen species. The probe has a low detection limit and operates under biological conditions. Moreover, the low cytotoxicity of B6S enables it to be utilized effectively for OCl imaging in living cells and tissues by using two-photon microscopy. The findings indicate that B6S has the capability of serving as a probe to explore the biological functions of OCl in living systems.