Abstract
Nitroaromatic explosives are the most commonly used military explosives. In this study, the known compound (E)-7-(diethylamino)-3-(3-(4-(dimethylamino)phenyl)acryloyl)-2H-chromen-2-one (hereinafter referred to as CKY) was employed as a fluorescent probe to systematically investigate its fluorescence response toward the nitroaromatic explosives 2,4,6-trinitrophenol (TNP) and 2,6-bis(picrylamino)-3,5-dinitropyridine (PYX). CKY showed rapid response (within 10 s) and pronounced fluorescence quenching toward TNP and PYX, with detection limits (LOD) of 3.37 µM and 1.86 µM, respectively. Combined with spectroscopic analysis and theoretical calculations, the fluorescence quenching mechanism of the probe toward the target analytes was discussed. In terms of practical applications, CKY-loaded test strips integrated with smartphone-based color recognition software were developed to establish a semiquantitative detection method for TNP and PYX. Furthermore, the response of the probe to exogenous TNP and PYX was evaluated in living HeLa cells, and satisfactory results were obtained. This work not only expands the application of the known compound CKY in the field of nitroaromatic explosive detection but also provides a candidate material for the rapid detection of TNP and PYX.