Fluorescent Chemosensor for Selective Detection of Phosgene in Solutions and in Gas Phase

The detection of highly toxic chemicals in a convenient, fast, and reliable manner is essential for coping with serious threats to humankind and public security caused by unexpected terrorist attacks and industrial accidents. In this paper, a highly selective fluorescent probe has been constructed through o-phenylenediamine covalently linking to coumarin (o-Pac), which can respond to phosgene in turn-on fluorescence mode. The response time is less than 0.5 min and the detection limit is as low as 3 nM in solutions. More importantly, the sensor exhibits good selectivity to phosgene over triphosgene and various acyl chlorides. Furthermore, a portable test paper has been fabricated with polystyrene membrane containing o-Pac for real-time selective monitoring of phosgene in gas phase.