Aggregation-induced emission active multianalyte sensor: Detection of pH, carbonate, bi-carbonate and nitroaromatics in water

An aggregation-induced emission (AIE) based multi-tasking probe DAAQ (5-(dimethylamino)-N-(9,10-dioxo-9,10-dihydroanthracen-2-yl)naphthalene-1-sulfonamide) has been reported for detecting multiple analytes such as anions (carbonate and bicarbonate ions) and nitroaromatic compounds (2,4-DNP and TNP). Probe DAAQ displayed the photophysical properties of aggregation-induced emission (AIE) in DMSO-water mixture and acidochromism and detected various analytes, making DAAQ a multi-tasking probe. DAAQ respond to carbonate and bicarbonate (CO32− and HCO3−) with a colour change from pale yellow to dark orange. The limit of detections (LOD) was estimated as 0.486 mg/L and 41.35 mg/L for CO32− and HCO3−, respectively. The applications of DAAQ were also explored to detect CO32− ions in water samples collected from various sources and soft drinks. Further, the probe also explored detecting neural aromatic compounds such as 2,4-DNP and TNP by a naked eye colour change and the LODs were calculated as 12.6 µM and 8.19 µM, respectively. DFT calculations were applied for the confirmation binding studies of DAAQ with multiple analytes. The sensing of 2,4-DNP and TNP were achieved through PET with a Turn-Off response. The sensing mechanisms were confirmed with 1H NMR experiments.