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

• Published in: Microchemical journal 2021-10, Vol.169, p.106584, Article 106584
• Main Authors: Ramesh, Subbiah, Kumaresan, Sudalaiyandi
• Format: Article
• Language: English
• Subjects: Cyanide anion; Intramolecular charge transfer; Naked-eye detection; Nucleophilic addition
• ISSN: 0026-265X; 1095-9149
• DOI: 10.1016/j.microc.2021.106584

[Display omitted] •A highly selective sensor for CN− over other common anions was prepared.•Sensor showed significant color change from purple to colorless.•Interruption in ICT progress and π-conjugation is attributed to the optical response.•The lowest detection limit for CN− was found to be 1.3 by colorimetric method.•Test strips were fabricated for on-site naked-eye detection of CN− ion in 100% water. 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 µM 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 π-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.