posted on 2023-11-24, 00:50authored byRaguraman Lalitha, Shu Pao Wu, Sivan Velmathi
Phosgene, an exceptionally hazardous gas, poses a grave
concern
for the health and safety of the general public. The present study
describes a fluorescent ratiometric probe for phosgene employing 2-(naphthalen-2-yl)
benzo[d]oxazol-5-amine (NOA) with an amino group as the recognition
site. NOA detects phosgene through the intramolecular charge transfer
mechanism. The electron-rich amine group of NOA attacks the electrophilic
carbonyl group of phosgene, resulting in a quick response within 20
s. NOA demonstrates a low detection limit of 60 nM while maintaining
high selectivity and sensitivity toward phosgene. The final product
was isolated and verified by nuclear magnetic resonance spectroscopy.
The probe can detect phosgene not just quickly in a solution environment
but also in its solid state. The probe’s applications in fingerprint
imaging and bioimaging are also demonstrated.