A Simple Colorimetric Detector of Symmetric 2-(Dialkylamino)ethanethiols as Precursors of v-Type Nerve Agents

A colorimetric detector tube of 2-(dialkylamino)ethanethiols as precursors of V-type nerve agents and their hydrolytic products was designed.The detector is based on a reaction of 2-(dialkylamino)ethanethiols with a chromogenic reagent 4-chloro-7-nitrobenzofurazan (NBD-Cl) in alkaline medium leading to characteristic coloured products.The detection limit in water is of 5 μg/ml, the optimum measurement range being up to 250 μg/ml.The detector also presented a response to some other warfare chemical agents, the colour shade being, however, different.Effects of disturbing substances and organic solvents were studied.