A new selective colorimetric and fluorescent chemodosimeter for HSO4- based on hydrolysis of Schiff base

Two new receptors 1 and 2 were prepared, and their chromogenic and fluorogenic behaviors toward various anions were investigated. Receptors 1 and 2 show exclusive response toward HSO4- ion and also distinguish HSO4- from other anions by different color changes in aqueous solution (CH3CN/H2O = 4/1, v/v). Between them receptor 1 selectively exhibits a pronounced HSO4--induced fluorescence enhancement. The detection limit for the HSO4- ion was determined as (0.24 +/- 0.03 mu M). Thus, the receptor 1 can be used as a colorimetric and fluorescent sensor for the determination of HSO4- ion. The sensing mechanism has been suggested to proceed via a hydrolysis process. The hydrolysis product has been isolated and further identified by H-1 NMR spectroscopy, ESI-MS analysis and X-ray diffraction. (C) 2013 Elsevier B.V. All rights reserved.