ThyminE-Hg2+-Thymine StructurE-based Detection of Hg2+ Enhanced by Gold Nanoparticle / 分析化学

ABSTRACT

A simple and sensitive method was developed for the detection of mercury ions with quartz crystal microbalance(QCM), based on the specific thymine(T)-Hg2+-T structure and gold nanoparticles. The gold nanoparticles were prepared by the citrate reduction method. In a self-assembled way, the particle surface was modified with the probe oligonucleotides which were partially replaced by 6-Mercaptohexan-1-ol to reduce the steric hindrance of hybridization. The sensitivity was optimized by the oligonucleotide with a strand length of 9bp and a T number of 7. The linear range was 5.0-100 nmol/L with a detection limit of 2.0 nmol/L. And Ca2+, Mg2+ and other metal ions had no significant interferences. This method was successfully applied for the detection of Hg2+in environmental water samples, with RSD less than 2.9% and recoveries of 97.3%-101.2%.