Two-stage sensing property via a conjugated donor-acceptor-donor constitution: application to the visual detection of
Ju-Hui Huang1, Wen-Hsien Wen, Yueh-Yang Sun
1Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
Abstract:
A conjugated donor-acceptor-donor molecule incorporating a central moiety of naphthyridine and two terminal moieties of di(hydroxyethyl)aniline connected by ethynyl bridges shows two-stage color changes on binding with mercury(II) ion in Me(2)SO/H(2)O (1:1) solution with a bathochromic shift from 450 to 498 nm, and then an extraordinarily large hypsochromic shift to 378 nm. In comparison, the corresponding donor-acceptor molecule weakly binds mercury(II) ion with a hypsochromic shift from 408 to 375 nm. Our designed sensor of the donor-acceptor-donor system shows high selectivity toward mercury(II) ion over other competing metal ions.
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