Diametrically disubstituted cyclam derivative having Hg2+-selective fluoroionophoric behaviors

Abstract

A new fluoroionophore has been synthesized by appending two signaling pyrenylacetamide subunits on the binding motif of 1,8-dimethylcyclam. The designed compound exhibited highly selective and sensitive fluoroionophoric behavior toward Hg2+ ions of excimer emission in aqueous dioxane (dioxane/H2O = 1:9, v/v) solution with a detection limit of 1.3 x 10(-6) M. The "ON-OFF" type signaling behavior of the fluoroionophore is due to the metal ion induced conformational changes from folded to open-winged conformations by exploiting the two nearby appended pyrenyl fluorophores.