Combined experimental and TD-DFT study of a highly sensitive AIE-based probe for the detection of water in organic solvents and its application in inkless writing

Abstract

The present manuscript highlights a newly synthesized pyrene-based probe (PyQ), which has a high affinity for the detection of water in water-miscible organic solvents. The efficient probe followed the principle based on aggregation-induced emission and showed its potential behavior as a sensor by detecting water in common water-miscible organic solvents by the fluorometric method. The chemosensor PyQ has identified water separately from many other solvents as its emission maxima in presence of water is found near 510 nm while for others it is around 410 – 440 nm. Moreover, in different water-miscible solvents by increasing the percentage of water, fluorescence studies have been carried out and were found that increasing water content in organic solvents increased the fluorescence intensity of the PyQ as well as provided a redshift to the emission intensities. Furthermore, the response of PyQ towards pH and the LOD and LOQ of PyQ towards a low level of water content in different organic solvents were determined. TD-DFT studies were carried out in the aqueous phase to clarify the optical and electronic properties of the probe. The moisture detection capacity of PyQ in presence of silica gel desiccant was also showcased. Finally, the utilization of PyQ in inkless writing and in reusable or rewritable paper strips disclosed its potential for real-life applications, which strengthened its use as a water sensor.