Direct colorimetric biosensing of mercury(II) ion based on aggregation of poly-(gamma-glutamic acid)-functionalized gold nanoparticles

作者：Guan Huanan^*; Liu Xiaofei; Wang Wei; Liang Jinzhong

来源：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 2014, 121: 527-532.

DOI：10.1016/j.saa.2013.10.107

• Colorimetric sensing
• Gold nanoparticles
• Poly-(gamma-glutamic acid)
• Mercury ion (Hg2+)

A simple and sensitive method for colorimetric detection of mercury ion (Hg2+) has been developed by using a poly (gamma-glutamic acid) functionalized gold nanoparticles (PGA-AuNPs) system. Electrostatic self-assembly technique was used to assemble negatively charged PGA on the surface of positively charged CTAB-capped AuNPs. With the increase of Hg2+ concentration, the color of the solution would progress from light red to purple blue. The results showed that the absorbance ratio (A(750)/A(580)) was linear with the Hg2+ concentration in the range of 0.01-10 mu M and from 50 to 300 mu M, with the correlation coefficients of 0.998 and 0.991, respectively. The reported probe is suitable for real-time detection of Hg2+ in water with the limit of detection (LOD) of 1.9 nM obtained by UV vis spectrum, and exhibits selectivity toward one order of magnitude over other metal ions. This approach was applied successfully to the determination of Hg2+ in tap water and mineral water, and the recoveries were from 90% to 103% and from 103.53% to 113%, respectively. The proposed method is rapid, low-cost and free of complex equipment, making it possible to analyze Hg2+ in various water samples.

• 出版日期2014-3-5
• 单位哈尔滨商业大学