A novel colorimetric and fluorogenic chemosensor for selective detection of Cu2+ ions in mixed aqueous media

Abstract

A novel and easy-to-synthesize chemosensor (L) was developed for the selective sensing of Cu²⁺ ions in mixed aqueous medium. Sensor L showed both colorimetric and spectral (UV-Vis and fluorescence) responses towards Cu²⁺, which was not affected in the presence of other surveyed metal ions (Na⁺, Mg²⁺, Al³⁺, K⁺, Ca²⁺, Fe²⁺, Co²⁺, Ni²⁺, Zn²⁺, Ba²⁺, Hg²⁺ and Pd²⁺). The 1 : 1 binding stoichiometry between Cu²⁺ and L was obtained using the Job's plot and ESI-MS analysis. The binding constant (K_a) of 1.56 x 10⁴ M⁻¹ for L–Cu²⁺ complex was calculated from the Benesei–Hildebrand plot. Further, theoretical calculations were performed using the density functional theory (DFT) method to complement the experimental results.