2,7-Diferrocenyl-3,6-diazaocta-2,6-diene: A highly selective dual fluorescent sensor for Zn~(2+) and Ag~+ and electrochemical sensor for Zn~(2+)

摘要

2,7-Diferrocenyl-3,6-diazaocta-2,6-diene (DFDD), obtained by condensation reaction of acetylferrocene and ethylenediamine, exhibits Zn~(2+) ion-induced enhancement of fluorescence intensity and Ag~+ ion-induced quenching of fluorescence intensity. The Zn~(2+) ion shifts the redox potential of DFDD from +0.660 V + 0.005 V to + 0.615 + 0.005 V as observed by cyclic voltammetry and square wave voltammetry. Ca~(2+), Mg~(2+), Mn~(2+), Fe~(2+), Co~(2+), Ni~(2+), Cu~(2+), Cd~(2+), Pb~(2+) and Hg~(2+) have very little effect on fluorescence intensity of DFDD. These metal ions together with Ag~+ ion have no effect on the electrochemistry of DFDD. Both, fluorescence and UV-visible spectroscopic data show a 1:1 interaction between DFDD and Zn~(2+) with binding constant 75 M~(-1). The applicability of DFDD as fluorescence sensor for Zn~(2+) ion has been shown in its estimation in commercial tablets.