On the synthesis and performance of a simple colorimetric and fluorescent chemosensor for Cu 2+ with good reversibility

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 277; p. 121245
• Main Authors: Wang, Bin, Xu, Weiling, Gan, Kaifeng, Xu, Ke, Chen, Qiaojie, Wei, Wei, Wu, Wei
• Format: Journal Article
• Language: English
• Published: England 05.09.2022
• Subjects: Colorimetry; Copper; Fluorescent Dyes; Ions; Spectrometry, Fluorescence; Cu(2+); Naked-eye detection; Chemosensor; Fluorescence
• ISSN: 1873-3557

A colorimetric and fluorescent chemosensor (CS1) for Cu based on the mechanism of internal charge transfer (ICT) has been successfully designed and prepared by simple condensation of 4 (diethylamino)salicylaldehyde and oxalyl dihydrazide. Cu in solution (DMSO/H O = 7:3, v/v) by 5 mM NaAc-HAc at pH 7.0 was determined through dual channels: (1) "naked-eye" observation, a visually dramatic color change from light green to orange, which can be used for qualitative determination of Cu ; (2) spectrofluorometry, which can quantificationally assay Cu . It provides a simple-to-use platform for reliable detection of Cu at concentrations ranging from 5.0 × 10 to 1.1 × 10 M with detection limit of 1.2 × 10 M, which is nearly 2 × 10 times lower than the maximum allowable level of inorganic Cu in drinking water (1.3 ppm, ∼20 µM) permitted by the EPA (Environmental Protection Agency), and the sensing detection of Cu ions was reversible.