Chromo-fluorogenic detection of Sarin, Tabun, and mustard gas mimics triggering the ring-opening reaction in a spirolactam-based probe

Abstract

Nerve agents are becoming serious issues for the healthy and sustainable environment in modern civilization. Strategically, we have designed and introduced a Schiff base triggered dual chromo-fluorogenic probe BASO via condensation reaction between rhodamine B hydrazide and 3-formyl chromone, which can selectively recognize different toxic target analytes helping a reference to a healthy and sustainable environment. The BASO probe displays enhanced pink photoluminescence extraordinarily due to the introduction of sarin, tabun, and mustard gas mimics diethylchlorophosphate (DCP), diethylcyanophosphonate (DCNP), and 2-chloroethyl ethyl sulfide (2CEES), in a 1:1 water–dimethyl sulfoxide (DMSO) mixture while native one was non-fluorescent. The opening of the spirolactam ring owing to the addition of DCP, DCNP, and 2CEES shows a noticeable pink colorimetric and pink color fluorometric change, which is readily detectable by the naked eye in the µM range in neutral medium and found to be better than numerous available chemosensor (Table S1). We have also fabricated simple paper strip-based test kits as portable and displayable handy photonic tools for on-site detection without any expensive instrumental techniques. The probe BASO has also been employed for detecting the vapor phase and soil sample analysis as a practical applicability. The simple, rapid detection techniques make our probe unique and have significant utility for the recognition of DCP, DCNP, and vesicant or blistering agents mimicking 2CEES.