A portable colorimetric and fluorescent sensor for the fast visual detection of phosgene

Phosgene is a suffocating toxic gas that seriously threatens human health and public security. In this work, we devised a colorimetric and fluorogenic chemosensor (BDY) for phosgene by using 3,5-dimethyl BODIPY as a fluorescent reporter and o-phenylenediamine as the recognition site. The BDY sensor displayed an obvious color change from yellow to pink in conjugation with a fluorescence turn-on response due to nucleophilic substitution and cyclization reactions with phosgene. BDY could detect phosgene with a rapid response (9 s), low detection limit (14 nM), and outstanding selectivity. Moreover, BDY-loaded test strips were prepared to serve as portable and sensitive kits for real-time visual monitoring phosgene with good performance.