A novel colorimetric and fluorescent probe based on indolium salt for detection of cyanide in 100% aqueous solution

• Published in: Dyes and pigments Vol. 168; pp. 175 - 179
• Main Authors: Li, Junjian, Chang, Zengyan, Pan, Xihao, Dong, Wei, Jia, Ai-Qun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2019
• Subjects: Cyanide; Intramolecular charge transfer; Nucleophilic addition; Water soluble; Cyanide; Water soluble; Intramolecular charge transfer; Nucleophilic addition
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2019.04.059

We reported a novel indolium salt -based colorimetric and fluorescent probe N1 for cyanide. The probe N1 showed a bleaching solution and fluorescence quenching toward CN− in 100% aqueous solution over other anions. In UV-vis and fluorescent spectrometry method, a large blue shift (261 nm), color bleaching and fluorescence quenching was observed. The minimum detection limit on fluorescence response of the probe N1 towards CN− was 3.34 × 10−7 mol/L. This probe N1 operates via intramolecular charge transfer (ICT) mechanism, because the nucleophilic attacking of CN− to the indol CN, the ICT progress was blocked with color changed and fluorescence quenched, which is further confirmed by 1H NMR, MS and DFT studies. Therefore, the synthesized probe would be a promising device for the detection of cyanide. [Display omitted] •A cyanide probe based on a conjugated indolium system.•The probe recognizes CN− selectively in 100% aqueous solution.•The detection of cyanide with probe can be performed clearly by color changes.