A highly selective benzildihydrazone based Schiff base chromogenic chemosensor for rapid detection of Cu2+ in aqueous solution

Schiff base sensors have the advantage of being used through easy, fast, cost-effective and reliable optical methods for sensing toxic metal ions in the environment. In this work, a, simple but highly specific benzildihydrazone based smart probe (1E, 2E)-1,2-diphenyl-1,2-bis((E)-(pyridin-2-ylmethylene) hydrazono) ethane (L) has been used for colorimetric detection of Cu2+ at physiological pH range. Binding interaction between L and various metal ions has been established by UV-Vis spectroscopic measurements, showing favourable coordination towards Cu2+ and almost no interference with the presence of other metal ions, i.e., Na+, K+, Mg2+, Ba2+, Mn2+, Fe3+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+ Ag+ and Al3+. L exhibited binding-induced colour change from colourless to reddish yellow with a detection limit of 3.66 x 10 (7) M, measured by spectroscopic methods, while colorimetric changes could be observed at naked eye for concentrations as low as 2.5 x 10 (6) M. L has been successfully applied for the determination of Cu2+ in real samples. (C) 2017 Elsevier B.V. All rights reserved.