Triphenylamine-based conjugated fluorescent sensor for highly sensitive detection of water in organic solvents

Two novel triphenylamine-based conjugated compounds were designed and synthesized. The compounds exhibited remarkable solvatochromism by changing emission colour from blue to yellow in polar organic solvents and were used as the fluorescent sensors for the detection of water in six common organic solvents, including acetonitrile, acetone, ethanol, tetrahydrofuran (THF), dimethylformamide (DMF) and dimethylsulfoxide (DMSO). Both sensors showed high sensitivity to detect water in the above-mentioned organic solvents in a wide range. The water sensing behavior of the sensors in acetonitrile was more effective, with a detection limit as low as 0.0079 v% and 0.0071 v%, respectively and a wide detection range (0–5.33 v%). Real application of the sensors was successfully carried out for detecting the unknown water content in commercial products, such as corn-starch, salt and sugar.