This work facilitates detection of bivalent copper ion by a simple Schiff base probe QNH based on a quinoxaline-naphthaldehyde framework. The detailed study in absorption spectroscopy and theoretical aspects and crystal study of the probe and probe-copper complex has been discussed. The detection limit of the probe in the presence of Cu2+ is 0.45 µM in HEPES-buffer/acetonitrile (3/7, v/v) medium for absorption study. The reversibility of the probe-copper complex has been investigated by EDTA. The selective visual detection of copper has been established also in gel form.
Keywords: Cu2+ colorimetric detection; ab initio calculations; absorption study; quinoxaline−naphthaldehyde conjugate.