Ratiometric fluorescent determination of Zn(II): a new class of tripodal receptor using mixed imine and amide linkages

Abstract

We synthesized a novel receptor with a unique combination of sp2 nitrogen (eCH]Ne) and carbonyl groups from amide linkages. These two moieties are judiciously incorporated into the receptor design such that these sites simultaneous binding a metal ion may generate a stable five-member ring. The receptor has been used to selectively detect Zn2þ through changes in the fluorescence spectra. Upon Zn2þ binding with the receptor, the fluorescence band shifted to enhance fluorescence intensity, allowing ratiometric determination of Zn2þ concentration.