Optical "Turn off" based selective detection and concomitant degradation of 2-chloroethyl ethyl sulfide (CEES) via Mg-porphyrazine complex immobilized on glass

Covalently assembled monolayers (CAMs) of Mg-porphyrazine complex on glass and silicon substrates were fabricated and employed as "Turn off" sensor for ppm level detection and degradation of a sulfur mustard analogue: 2-chloroethyl ethyl sulfide (CEES). The detection process was read-out optically via an off-the-shelf UV/Vis spectrophotometer in transmission mode. Monolayer based sensor system was shown to be quite robust and stable, sufficiently accurate and reversible under given experimental conditions. Notably, the sensor system exhibited marked selectivity for CEES when exposed exclusively or in mix to different potent analytes. Moreover, action of KMnO₄ on monolayer-CEES complex lead to CEES degradation and resetting of the sensor to its native state for reuse.