A highly sensitive colorimetric chemodosimeter for cyanide anion by Michael addition based on a coumarin derivative

Abstract

A colorimetric and fluorescent cyanide chemosensor L1 bearing a coumarin group has been designed and synthesized. It showed immediate visible color changes from yellow to colorless and blue fluorescence enhancement when CN⁻ was added. The mechanism of the CN⁻ anion recognition process was examined using ¹H NMR titration, FT-IR spectroscopy, ESI-MS and DFT calculations. The sensor was highly sensitive with a detection limit of 7.72 × 10⁻⁸ M of CN⁻. Test strips based on the sensor L1 were fabricated, which could act as a convenient and efficient CN⁻ test kit to detect CN⁻ for “in-the-field” measurements.