A portable and accessible Probe: Smartphone assisted colorimetric nerve agent detection

Abstract

Due to the extreme toxicity and volatility of organophosphorus nerve agents, the development of colorimetric sensors plays a vital role in detecting these agents in both solution and vapors. Herein, we have developed a low-cost probe based on 2-Anilino-6-dibutylamino-3-methylfluoran (ODB-2) for the detection of nerve agents. This probe can achieve a sensitive response to diethyl chlorophosphate (DCP) in both solution and vapors. The limit of detection (LOD) for DCP in solution was determined to be 0.36 µmol/L, while the LOD for DCP in vapors was determined to be 0.13 ppb. Meanwhile, the response time to reach 80 % of the discoloration endpoint was only 5.2 s, which meet the requirements for practical application. The detection mechanism of this sensor was studied by using 1H NMR, MS, SEM-EDS, and FT-IR. Furthermore, we integrated ODB-2 into the self-assembled portable detection system, enabling on-site and real-time monitoring of DCP vapors with the LOD of 0.23 ppb. The use of this affordable detection system is highly significant for detecting nerve agents.