Schiff Base Ligand 3-(-(2-Hydroxyphenylimino) Methyl)-4H-Chromen-4-One as Colorimetric Sensor for Detection of Cu2+, Fe3+, and V5+in Aqueous Solutions

Abstract

The ligand 3-(-(2-hydroxyphenylimino) methyl)-4H-chromen-4-one (SL) has been synthesized and examined as a chemosensor for some metal ions in aqueous solutions based on colorimetric analysis. Color changes were monitored using UV-visible spectroscopy. Binding stoichiometry and limit of detection (LOD) were estimated using titration experimentation based on UV-visible absorbance and Job's plot. The synthesized ligand was tested for selectivity in the presence of several cations and was examined for possible utility as a chemosensor in real water samples. The results indicated sensing ability and selectivity for Cu2+, Fe3+, and V5+. Stable complexes were formed between SL and Cu2+, Fe3+, and V5+, and the ligand-to-metal binding stoichiometry was found 2: 1 in the SL-Cu2+ and SL-Fe3+ complexes, and 1: 1 in the SL-V5+ complex. The results of LOD and bending constant were (7.03 μM, 1.37 × 104 M-1), (5.16 μM, 2.01 × 104 M-1), and (5.94 μM, 1.82 × 104 M-1) for Cu2+, Fe3+, and V5+, respectively.