Fluorescent Sensor Based on 2-Cyano-1,10-phenanthroline for Fe2+ ion Analysis in Acetonitrile

Abstract

Fluorescent sensors for the detection and measurement of Fe2+ will be actively investigated in this paper, as this metal ion is a significant environmental pollutant and essentials element in biological systems. For most of the reported Fe2+ fluorescent sensors, the binding of the metal ion cause a quenching of the fluorescent emission. Only a few sensors in which the binding of the metal ions causes an increase in the fluorescence have been reported (Zhaochao, Yi Xiao and Xuhong Qian, 2005) . To increase the selectivity and sensitivity of a measurement, ratiometric measurements are utilized. Ratiometric measurements involve the observation of changes in the ratio of the intensities of the absorption or the emission at two wavelengths. However, ratiometric sensors for the detection of Fe2+ are very rare. We designed and synthesized the fluorescent sensors (1), 2-Cyano-1,10-phenanthroline which contain fluorophore and ionophore and show the static quenching, fluorescent enhancement and dynamic quenching for a range of concentration. The fluoroionophore (1) shows high selectivity for Fe2+ with detection limit 3.6×10-9 M.