Jiang Zhiliang, Fan Yanyan, Chen Menglin, Liang Aihui, Liao Xianjiu, Wen Guiqing, Shen Xingcan, He Xingcun, Pan Hongchen, Jiang Hesheng
Guangxi Key Laboratory of Environmental Engineering, Protection and Assessment, Guangxi Normal University, Guilin 541004, China.
Anal Chem. 2009 Jul 1;81(13):5439-45. doi: 10.1021/ac900590g.
Single-strand DNA (ssDNA) was used to modify 10 nm nanogold to obtain an aptamer-modified nanogold resonance scattering (RS) probe (AussDNA) for detection of Hg(2+). In the presence of NaCl, Hg(2+) interacts with AussDNA to form very stable double-strand T-Hg(2+)-T mismatches and release nanogold particles that aggregate to large nanogold clusters causing the RS intensity at 540 nm to be enhanced linearly. On those grounds, 1.3-1667 nM Hg(2+) can be detected rapidly by the aptamer-modified nanogold RS assay, with a detection limit of 0.7 nM Hg(2+). If the large nanogold clusters were removed by membrane filtration, the excess AussDNA in the filtrate solution exhibits a catalytic effect on the new Cu(2)O particle reaction between NH(2)OH and Cu(2+)-EDTA complex at 60 degrees C. The excess AussDNA decreased with the addition of Hg(2+), which led the Cu(2)O particle RS intensity at 602 nm to decrease. The decreased RS intensity (DeltaI(602nm)) had a linear response to Hg(2+) concentration in the range of 0.1-400 nM, with a detection limit of 0.03 nM Hg(2+). This aptamer-modified nanogold catalytic RS method was applied for the detection of Hg(2+) in water samples, with sensitivity, selectivity, and simplicity.
单链DNA（ssDNA）用于修饰10纳米的纳米金，以获得用于检测Hg(2+)的适配体修饰的纳米金共振散射（RS）探针（AussDNA）。在NaCl存在的情况下，Hg(2+)与AussDNA相互作用形成非常稳定的双链T-Hg(2+)-T错配，并释放纳米金颗粒，这些颗粒聚集形成大的纳米金簇，导致540纳米处的RS强度线性增强。基于此，通过适配体修饰的纳米金RS分析法可快速检测1.3 - 1667 nM的Hg(2+)，检测限为0.7 nM Hg(2+)。如果通过膜过滤去除大的纳米金簇，滤液溶液中过量的AussDNA在60℃下对NH(2)OH与Cu(2+)-EDTA络合物之间新的Cu(2)O颗粒反应具有催化作用。随着Hg(2+)的加入，过量的AussDNA减少，这导致602纳米处的Cu(2)O颗粒RS强度降低。降低的RS强度（ΔI(602nm)）在0.1 - 400 nM的Hg(2+)浓度范围内对Hg(2+)浓度呈线性响应，检测限为0.03 nM Hg(2+)。这种适配体修饰的纳米金催化RS方法应用于水样中Hg(2+)的检测，具有灵敏度高、选择性好和操作简便的特点。
