Selective and Sensitive Detection of Cyanide Based on the Displacement Strategy Using a Water-Soluble Fluorescent Probe

A water-soluble fluorescent probe (c-ggh) was used for the highly sensitive and selective detection of cyanide (cn-) in aqueous media based on the displacement strategy. due to the presence of the recognition unit ggh (gly-gly-his),the probe c-ggh can coordinate with cu2+ and consequently display on-off type fluorescence response. furthermore,the in situ formed nonfluorescent c-ggh-cu2+ complex can act as an effective off-on type fluorescent probe for sensing cn- anion. 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 c-ggh-cu2+ allowed detection of cn- in aqueous solution with a lod (limit of detection) of 0.017 mol/l which is much lower than the maximum contaminant level (1.9 mol/l) for cn- in drinking water set by the who (world health organization). the probe also displayed excellent specificity for cn- towards other anions,including f-,cl-,br-,i-,scn-,p o 4 3-,n 3-,n o 3 -,aco-,s o 4 2-,and c o 3 2-. © 2016 ming la et al.