Abstract:Cyanide is considered to be one of the most toxic species in food while the existing detection methods involve complex operation and will produce toxicity to inspectors. In this study, a water-soluble fluorescent probe(C-GGH) was synthesized by HOBT/DIC protocol in solution using 7-diethylaminocoumarin-3-carboxylic acid, Glycine and Histidine. Due to the presence of the recognition unit GGH, the probe C-GGH can conjugated with Cu2+ to formed non-fluorescent C-GGH-Cu2+ complex. Due to the strong binding affinity of CN- to Cu2+, CN- can extract Cu2+ from C-GGH-Cu2+ complex, leading to the release of C-GGH and the recovery of fluorescent emission of the system. The probe allowed detection of cyanide in aqueous solution with a LOD (limit of detection) of 0.017 μmol/L which is much lower than the maximum contaminant level (0.385 μmol/L) for cyanide in mineral water set by national standard (GB 8537—2008). The probe also displayed excellent specificity for CN- towards other anions, including F-, Cl-, Br-, I-, SCN-, PO3-4, N3-, NO-3, AcO-, SO2-4, and CO2-3. The method developed in this study received the same results as national standard method (GB/T 5009.48—2003, GB/T 5009.36—2003, GB/T 8538—2008), but more simple and quick in real sample detection.