Theoretical insights into a colorimetric azo-based probe to detect copper ions.

ABSTRACT: In the present study, a colorimetric azobenzene-based probe (AZO 1) was reported that exhibits high selectivity toward Cu²⁺ and undergoes a red to yellow colour change upon its detection. Density functional theory (DFT) calculations were carried out to investigate the mechanism of the probe discoloration. The differences in the binding energies of complexes of 2 : 1 and 1 : 1 stoichiometry indicated that a two-step complexation process takes place as the Cu²⁺ content increases. However, the calculated absorption spectra suggested that a significant colour change would only be observed for the 1 : 1 AZO 1 : Cu²⁺ complex. A HOMO-LUMO electronic transition was a key factor for the blue shift of the absorption bands of the probe. Further studies indicated that

SUBMITTER: Pang J 

PROVIDER: S-EPMC9054711 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature