Ke Wang, Lixue Yang, Chuan Zhao
Mar 15, 2013
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Influential Citations
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Journal
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
Abstract
4-Amino-7-nitro-2,1,3-benzoxadiazole (ANBD) usually serves as a scaffold for developing fluorescent probes. In this paper, however, ANBD has been used as a chromogenic unit to design a new colorimetric probe, 4-(8-quinolyl)amino-7-nitro-2,1,3-benzoxadiazole (1), for rapid and visual detection of Hg(2+). The reaction of 1 with Hg(2+) in NaH(2)PO(4)-Na(2)HPO(4) buffer (pH 7.0) containing 70% (v/v) acetonitrile forms a 1:1 complex, accompanying a red shift of the absorption maximum from 482 nm to 557 nm and a distinct color change from orange to violet. Moreover the color reaction exhibits a high selectivity and sensitivity to Hg(2+) only, instead of other common metal ions. This behavior may be ascribed to the formation of a specific 1-Hg(2+) complex, which is supported by (1)H NMR titration experiments. The present study is not only a supplement to the detection method of Hg(2+), but also a merit to the chemistry of 4-amino-7-nitro-2,1,3-benzoxadiazole.