Organoselenium-based BOPHY as a sensor for detection of hypochlorous acid in mammalian cells

Phenylselenide substituted BOPHY probes (BOPHY-SePh and PhSe-BOPHY-SePh) were synthesized and characterized by NMR spectroscopy and single-crystal XRD. Both the probes selectively detect HOCl in water with high sensitivity over other reactive oxygen species. A fluorescence “turn-on” event was attained due to cease of the PET process through transformation of selenide to selenoxide. Both the probes react with HOCl in less than 1 s. PhSe-BOPHY-SePh probe depicted low background fluorescence due to presence of two phenylselenide groups at BOPHY. PhSe-BOPHY-SePh probe has a low detection limit (0.63 μM) than BOPHY-SePh probe (1.08 μM). The bioimaging studies of both the probes were carried out in MCF 7 cells. Both the probes exhibited a good fluorescence response for HOCl in vitro and in mammalian cells. In addition, the probes showed reversibility with all bio-thiols, which was validated in MCF 7 cells using GSH. [Display omitted] •First organoselenium-based BOPHY probes were synthesized and confirmed with XRD.•The probes selectively and sensitively detect HOCl in water with “turn on” response.•Two phenylselenide quenched more fluorescence than one phenylselenide group on BOPHY.•The probe with one Se gave a faster response compared to the probe with two Se.•Utility of the probes for exogenous and endogenous HOCl was confirmed in MCF 7 cells.