Elsevier, Sensors and Actuators B: Chemical, (177), p. 1189-1197, 2013
DOI: 10.1016/j.snb.2012.12.043
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Three salicylaldehyde derivatives, namely 5-nitrosalicylaldehyde fluorescein hydrazone (1), 5-diethylaminosalicylaldehyde fluorescein hydrazone (2), and di(5-diethylamino salicylaldehyde) hydrazide (3), were synthesized and characterized. Their ability to recognize copper ions was investigated by UV-visible and fluorescence spectroscopies, with 2 shown to be an optimal probe for effective detection of Cu2+. More importantly, to explore the optical properties of these probes, and their mechanism for recognition of Cu2+ ions, B3LYP/6-311+G(d,p) density functional calculations were used to investigate the molecular orbitals and electronic excitations of each probe. In addition, because the 2-Cu2+ complex exhibits anion-induced fluorescence enhancement, we illustrate its potential application to bioimaging. (c) 2012 Elsevier B.V. All rights reserved.