基于单链核酸-纳米金-汞模拟酶的汞离子检测方法研究

Study on Detection of Hg(Ⅱ) Based on Single Nucleic Acid/Au NPs/Mercury Ion Enzyme Mimetics

将汞离子（Hg2＋）沉积到吸附单链核酸（ssDNA）的纳米金（AuNPs）表面后,可以提高纳米金的模拟过氧化物酶活性,基于此原理可实现Hg2＋的高灵敏检测。研究发现ss DNA能够促进Au NPs-Hg2＋的类似过氧化物酶活性,且随着ss DNA浓度的增加,该作用呈增强趋势。在优化反应条件下,将ss DNA-Au NPs-Hg2＋模拟过氧化物酶用于Hg2＋的检测,Hg2＋的检测线性范围为10-1 000 nmol/L,检出限可达3.0 nmol/L。该检测方法具有简便快速、成本低、稳定性高等优点,有望用于环境、食品等样品中Hg2＋的检测。

Mercury（ Hg2＋） ions deposited on the surface of gold nanoparticles （AuNPs） absorbing single strand DNA （ssDNA） can promote the peroxidase-like activity of AuNPs. Based on this, a highly sensitive detection of Hg2＋ was developed. Here it was found that ssDNA can promote the ac- tivity of AuNPs- Hg2＋ mimetic peroxidase due to the adsorption of ssDNA on the AuNPs surface. The catalytic activity of AuNPs - Hg2＋ mimetic peroxidase increases with increase of ssDNA concen- tration. The ssDNA - AuNPs - Hg2＋ mimetic peroxidase can be applied in the detection of Hg2＋ in a linear range of 10 - 1 000 nmol/L with a detection limit as low as 3.0 nmol/L under optimized condi- tion. The method was simple, rapid, low cost and stable, and had high application potential to de-tect Hg2＋ in the environment, food and other samples.