Ultrasensitive dicyanoisophorone-based near-infrared fluorescent probe for rapid and specific detection of thiophenols in river water

Thiophenols are a class of highly toxic pollutant compounds, which can cause severe damage to the central nervous system and other nervous systems after long-term exposure. Therefore, it is of significance to develop an effective method to detect trace thiophenols in the environment. Herein, we synthesized a dicyanoisophorone-based near-infrared fluorescent probe (probe 1 ) with large stokes shift ( λ em − λ abs = 203 nm) for the selective detection of thiophenols. Probe 1 exhibited very high response speed (less than 200 S), sensitivity, and selectivity towards thiophenols, regardless of the presence of aliphatic thiols and other analytes. The detection limit was as low as 3.4 nM and the signal-to-background ratio of fluorescence intensity reached 30. Moreover, probe 1 displayed ultrasensitivity and high reliability in the quantitative detection of trace thiophenol in three river water samples.