An Efficient Way for the Recognition of Zinc Ion via the Fluorescence Enhancement

Abstract

This study concentrates on the spectral and complexing properties of a tetraoxycalix[2]arene[2]triazine derivative bearing two bipyridines (Calix-BIPY2) in a mixture of acetonitrile∶chloroform (4∶1, V∶V). The results show that Calix-BIPY2 has a highly selectivity and sensitivity towards Zn 2＋ over various competing cations (K ＋ , Cu 2＋ , Cd 2＋ , Co 2＋ , Fe 2＋ , Hg 2＋ , Ag ＋ , Al 3＋ and Pb 2＋ ). The complexation of Zn 2＋ induces a remarkable fluorescence enhancement due to combination effects of the binding strength, electron spins state of metal ions, photoinduced charge transfer (PCT) and the rigidity of the complexing unit offered by calixarene-based hosts.