A Colorimetric and Fluorescent Chemosensor for the Selective Detection of Cu2+ and Zn2+ Ions
Min Seon Kim1, Tae Geun Jo1, Hye Mi Ahn1
1Department of Fine Chemistry and Department of Interdisciplinary Bio IT Materials, Seoul National University of Science and Technology, Seoul, 139-743, South Korea.
Abstract:
A new bi-functional chemosensor 1 based on 3,5-dichlorosalicylaldehyde and 2-(methylthio)aniline has been synthesized. It can detect Cu2+ with a color change from pale yellow to dark yellow in aqueous solution. The selective mechanism of 1 for Cu2+ was proposed to be the enhancement of the intramolecular charge transfer (ICT) band, which was explained by theoretical calculations. The sensor 1 could be used to detect and quantify Cu2+ in water samples. In addition, the sensor 1 displayed "turn-on" fluorescence response only to Zn2+, based on an effect of chelation-enhanced fluorescence (CHEF). Therefore, 1 can serve as a 'single sensor for two different targets' with dual modes.
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