A Novel Indolium-Based Fluorescent Probe for Fast Detection of Cyanide

A novel indolium-based fluorescent probe for the detection of CN^- was developed based on the conjugation of 1, 2, 3, 3-Tetramethyl-3H-indolium iodide and 2-acetyl benzothiophene. The introduction of external CN^- caused a nucleophilic attack to the quaternary amine salt structure in the probe and resulted in the departure of iodide ions and the steric rotation of the index salt group, which caused fluorescence quenching. The titration experiments showed that the probe had rapid qualitative and quantitative analysis capabilities for CN^-. Moreover, the relevant biocompatibility experiments also demonstrated the potential application value of the probe.