化学学报 ›› 2009, Vol. 67 ›› Issue (18): 2139-2143. 上一篇    下一篇

研究论文

纳米金探针检测Hg 2+离子

鲍军方a 何 鹏a 于锡娟*,a 姜世丽b 颜清云a   

  1. (a青岛科技大学化学与分子工程学院 青岛 266042)
    (b山东省莱阳卫生学校内科教研室 莱阳 265200)
  • 投稿日期:2008-09-16 修回日期:2009-02-20 发布日期:2009-12-31
  • 通讯作者: 于锡娟

Detection of Hg 2+ Using Gold Nanoparticle Probes

Bao, Junfanga He, Penga Yu, Xijuan*,a Jiang, Shili b Yan, Qingyuna   

  1. (a College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042)
    (b Department of Internal Medicine, Laiyang Medical School, Laiyang 265200)
  • Received:2008-09-16 Revised:2009-02-20 Published:2009-12-31

利用Hg2+的核酸适体修饰纳米金形成探针建立了一种定量检测Hg2+离子的方法. Hg2+适体吸附在纳米金表面, 使纳米金的稳定性增强, 抑制氯化钠对纳米金的团聚作用. 溶液中有Hg2+离子存在时, 由于适体与纳米金的吸附作用小于适体与Hg2+离子的亲和作用, 纳米金失去适体保护在氯化钠作用下发生团聚. 溶液颜色由红变蓝, 紫外-可见光谱最大吸收峰由520 nm红移至620 nm. 在优化条件下, 吸光度的比值(A620/A520)与Hg2+离子浓度在5.0×10-9~7.2×10-7 mol•L-1范围内呈线性关系, 检测限可达3.3×10-10 mol•L-1. 研究了K+, Ca2+等常见离子的干扰, 结果表明该方法具有良好的选择性.

关键词: 纳米金, 核酸适体, Hg2+, 紫外-可见光谱

A method was developed for Hg2+ quantitative determination using the Hg2+ aptamer to modify gold nanoparticles (AuNP). The aptamer would adsorb onto the AuNP and help to enhance the AuNP stability against salt-induced aggregation. But this attraction was weaker than the affinity between the target (Hg2+) and the aptamer. So if the proper Hg2+ and aptamer were put into the AuNP solution, addition of salt resulted in aggregation of AuNP that led to red-to-blue color change. And the maximum absorption wavelength would change from 520 to 620 nm. Before detecting Hg2+, the concentrations of NaCl and aptamer were optimized, and the appropriate pH was chosen. Under optimal conditions, the absorption ratio A620/A520 was proportional to the concentration of Hg2+ in the range of 5.0×10-9 to 7.2×10-7 mol•L-1 and the detection limit was 3.3×10-10 mol•L-1. Interferences from selected inorganic ions were investigated and the proposed method was simple and sensitive.

Key words: gold nanoparticle, aptamer, Hg2+, UV-Vis spectra