Resonance scattering spectral detection of ultratrace Hg(II) using herring sperm DNA modified nanogold probe as catalyst

✍ Scribed by Guiqing Wen; Aihui Liang; Zhiliang Jiang; Xianjiu Liao; Jianfu Li; Hesheng Jiang

• Book ID: 101715168
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 337 KB
• Volume: 25
• Category: Article
• ISSN: 1522-7235
• DOI: 10.1002/bio.1161

✦ Synopsis

Abstract

Herring sperm DNA (hsDNA) was used to modify 10 nm nanogold to obtain a resonance scattering (RS) probe (AuhsDNA) for detection of Hg^2+^. In the presence of salt, Hg^2+^ interacts with AuhsDNA to form stable Hg^2+^–hsDNA complexes, and releases nanogold particles to form larger nanogold clusters that can be removed by membrane filtration. The excess AuhsDNA in the filtrate solution exhibits a catalytic effect on the reaction between hydroxylamine (NH~2~OH) and Cu(II). The excess AuhsDNA decreased with the addition of Hg^2+^, which led the RS intensity at 602 nm to decrease. The decreased RS intensity (Δ__l__~602 nm~) had a linear response to Hg^2+^ concentration in the range of 0.4–400 nM, with a detection limit of 0.2 nM Hg^2+^. This RS method was applied for the detection of Hg^2+^ in water samples, with sensitivity, selectivity and simplicity. Copyright © 2009 John Wiley & Sons, Ltd.