A highly selective coumarin-based chemosensor for naked-eye detection of cyanide anions via nucleophilic addition in pure aqueous environment

A coumarin-based naked-eye colorimetric sensor IC has been developed for the highly selective detection of CN- over other common anions in pure aqueous solution. The nucleophilic addition of CN- inhibits ICT progress in IC, which is attributed to the color change from purple to colorless. The lowest detection limit for cyanide ion was estimated to be 1.3 and 0.8 mu M based on absorption and emission spectral studies, respectively. The theoretical studies were also supported the optical responses of IC towards CN- was due to the interruption of pi-conjugation and blocking ICT progress in IC. For more convenience, paper-based test strips displayed remarkable and easy-to-use naked-eye colorimetric detection of CN- in pure water as low as 25 ppm.

Automated summary

By developing a coumarin-based naked-eye colorimetric sensor, selective detection of CN- has been achieved in pure aqueous solution with a color change indication. Based on absorption and emission spectral studies, the lowest detection limit of cyanide ion can be estimated accurately.