ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Photoinduced electron transfer-based fluorescent sensor for sensing diethyl cyanophosphonate

Nikita Patel, Preeti Ashokkumar Chaudhran, Sheetal Yadav, and Abha Sharma

Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Raebareli, India

E-mail: abha.sharma@niperraebareli.edu.in

Received: 3 November 2022  Accepted: 25 September 2023

Abstract:

In this work, 2-phenylimidazo[1,2-a]pyridine-based probe was designed, synthesized, and evaluated for the selective detection of diethyl cyanophosphonate (DECP), a tabun mimic, chemical warfare agent (CWA). The addition of DECP produces a rapid fluorescence color change from blue to green, which is visualized at wavelength of 365 nm. Mechanistic investigation indicates phosphorylation of the amino unit of 4-(imidazo[1,2-a]pyridin-2-yl)aniline in the presence of DECP, inhibits photoinduced electron transfer (PET) phenomenon that subsequently produced a fluorescence color change. The probe was found to be selective towards DECP with no detectable interference with other analytes. Further, immobilization on a paper strip, the fluorogenic probe can detect organophosphorus nerve agent simulant (DECP) in solution as well as in the vapor phase, making the system a viable choice for chemical warfare agent detection in the field. The limit of detection (LOD) and limit of quantification (LOQ) for DECP was found to be 0.23 μM and 0.70 μM, respectively, with respect to the linear field concentation range of 0, 0.4, 0.8, and 1.2 μM, the standard deviation found as 17.19 whereas, RSD% = 2.89. The probe not only shows high sensitivity and selectivity in solution but can also be applied for the recognition of DECP in the vapour state with significant color changes.

Keywords: CWA; 2-phenylimidazo[1,2-a]pyridine; Photoinduced electron transfer; Fluorescent Probe; DECP; Sensing

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03114-6

Chemical Papers 78 (2) 887–896 (2024)