A simple and efficient colorimetric anion sensor based on a thiourea group in DMSO and DMSO-water and its real-life
Jie Shao1, Hai Lin, Hua-Kuan Lin
1Department of Chemistry, Nankai University, Tianjin 300071, People's Republic of China.
Talanta
|July 1, 2008
Abstract:
An efficient colorimetric sensor with a thiourea moiety as binding sites and p-nitrophenylhydrazine as a signaling unit has been synthesized by only one single-step procedure. Selectivity for anions with the distinct geometry (tetrahedral, trigonal planar and spherical) has been investigated in dry DMSO and even in DMSO/H(2)O (95:5, v/v) solutions through the naked-eye experiment, UV-vis titration and (1)H NMR titration techniques. In particular, the fluoride of toothpaste can be detected qualitatively by the sensor 1.
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