A Double-Site Chemodosimeter for Selective Fluorescence Detection of a Nerve Agent Mimic

Abstract

A novel two-site chemodosimeter (SWJT-4) based on fluorescein skeleton to detect diethyl chlorophosphate (DCP) was designed and synthesized. It is a turn-on fluorescent probe for DCP with good selectivity and obvious color change in aqueous solution. Interestingly, the two oxime groups of SWJT-4 as dual response sites initiated different reactions with DCP to form a cyano group and an isoxazole ring, respectively. The corresponding mechanism was confirmed by 1H NMR, MS and DFT calculation. Moreover, SWJT-4 could be used as a fluorescent test paper to detect DCP vapor.

Fluorometric detection of a chemical warfare agent mimic (DCP) using a simple hydroxybenzothiazole–diaminomaleonitrile based chemodosimeter

“…They are preferred over chemosensors for their high selectivity and sensitivity and they show distinct ratiometric fluorescent responses in presence of DCP. 29–32…”

A salicylaldoximate-based AIE probe for the detection of the nerve agent simulant DCP

“…However, it seemed that the reaction between the salicylaldoximate structure and OP nerve agents in different studies did not generate the same structural product. Four possible products have been proposed: the first is the phosphoric salicylaldoxime ester compound from the phosphorylation of the oxime group; 12,[27][28][29] the second is the double phosphorylation product of the oxime group and the phenolic hydroxyl group; 29 the third is the arylisoxazole compound afforded via displacement of the formed oxime's OP ester and cyclization; 11,30,31 the last one is the ortho-hydroxy arylnitrile product generated via the rearrangement of an arylisoxazole intermediate. 9,32 In addition, the last ortho-hydroxy arylnitrile has the possibility of further phosphorylation by attacking the phosphorus(V) center of OP compounds.…”

Ditopic Chemodosimeter for Selective Detection of Nerve Agent Tabun Simulant DCNP

“…Their selective detection is of paramount importance for armed forces and first responders in order to select the correct tools for medical countermeasures on exposure to them [1] . Though, a variety of detection systems based on electrochemistry, [2] surface acoustic wave (SAW) devices, [3] micro‐cantilevers, [4] photonic crystals, [5] ion mobility spectrometry, [6] enzymatic assay, [7] etc have been developed, they suffered from limitations including non portability, operational complexity, difficulty in real time monitoring, poor selectivity and sensitivity, etc.Owing to these reasons, research on the development of optical chemical sensors, measuring the changes in their optical properties (either fluorescence or color) by virtue of their interaction with nerve agents or their simulants, gained momentum as these were cheap, easy to operate, fast and portable [8–19] . Among the chromo‐fluorogenic molecular sensing probes, the supramolecular sensors, involving non‐covalent interactions with analyte undergo multiple interactions (multitopic approach) with the analyte leading to selective detection [20] .…”