A simple quinazolinone-isophorone based colorimetric chemosensor for the reversible detection of copper (II) and its application in real samples

Abstract

This paper presents the design and synthesis of a new colorimetric chemosensor based on quinazolinone-isophorone (IAH) to colorimetrically detect Cu2+ ions with high selectivity in the aqueous acetonitrile solution.In the presence of Cu2+, the synthesized compound had a remarkable colorimetric response from yellow to colorless, which could be seen with naked eyes. The analytical performance features of the proposed Cu2+ sensor are studied. The chemosensor can be applied to the quantification of Cu2+with a significant detection limit of 141 nM. The experiment results show that the colorimetric response of IAH towards Cu2+is pH-independent under a wide range of pH from 3.0 to 10.0. Moreover, the colorimetric response of IAH+Cu2+ can be reversed with EDTA multiple times. The mechanism of interaction between the IAH and Cu2+ions has been studied by Job's plot, HRMS, and 1HNMR titration experiments, which confirmed 1:1 binding stoichiometry between IAH and Cu2+. The real-time application of Cu2+ detection was demonstrated in test paper-based detection, constructing the molecular logic gate and quantifying Cu2+in water samples.