1. Successive and Specific Detection of Hg2+ and I– by a DNA@MOF Biosensor: Experimental and Simulation Studies
- Author
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Ning Liu, Bin Sun, Ke-Yang Wu, Bao-Ping Xie, Jin-Xiang Chen, Wen-Jun Duan, Pei-Pei Hu, Ling-Yan Zhai, and Wen-Hua Zhang
- Subjects
Detection limit ,Fluorophore ,Ethylene ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Fluorescence ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,Bromide ,A-DNA ,Physical and Theoretical Chemistry ,0210 nano-technology ,Biosensor ,DNA - Abstract
A 2D metal–organic framework (MOF) of {[Cu(Dcbb)(Bpe)]·Cl}n (1, H2DcbbBr = 1-(3,5-dicarboxybenzyl)-4,4′-bipyridinium bromide, Bpe = trans-1,2-bis(4-pyridyl)ethylene)) has been prepared. MOF 1 associates with the thymine-rich (T-rich), single-stranded probe DNA (ss-DNA, denoted as P-DNA) labeled with fluorophore FAM (FAM = carboxyfluorescein) and quenches the FAM emission to give a nonemissive P-DNA@1 hybrid (off state). The P-DNA in the hybrid subsequently captures the Hg2+ to give a rigid double-stranded DNA featuring T–Hg2+–T motif (ds-DNA@Hg2+) and detach from MOF 1, triggering the recovery of the FAM fluorescence (on state). Upon subsequent addition of I–, Hg2+ was further sequestrated from the ds-DNA@Hg2+ duplex, driven by the stronger Hg–I coordination. The released P-DNA is resorbed by MOF 1 to regain the initial P-DNA@1 hybrid (off state). The P-DNA@1 sensor thus detects Hg2+ and I– sequentially via a fluorescence “off–on–off” mechanism. The sensor is highly selective and sensitive, yielding detec...
- Published
- 2018
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