金微电极微分脉冲伏安法测定甲基汞

1)安徽工程大学机械与汽车工程学院,安徽芜湖241004; 2)合肥工业大学工业与装备技术研究院,安徽合肥230009; 3)皖西学院机械与车辆工程学院,安徽六安237014

电化学分析; 金微电极; 甲基汞; 微分脉冲伏安法; 痕量检测; 抗干扰性

Determination of methylmercury by differential pulse voltammetry with gold microelectrode
NI Xiaoxi1, HUANG Zhongjia1, CHEN Xing2, and JIA Weijian3

1)School of Mechanical and Automotive Engineering, Anhui Polytechnic University, Wuhu 241004, Anhui Province, P.R.China;2)Institute of Industry and Equipment Technology, Hefei University of Technology, Hefei 230009, Anhui Province, P.R.China;3)School of Mechanical and Vehicle Engineering, West Anhui University, Lu'an 237014, Anhui Province, P.R.China

electrochemical analysis; gold microelectrode; methylmercury; differential pulse voltammetry; ultra-trace detection; interference

DOI: 10.3724/SP.J.1249.2021.04367

备注

甲基汞是一种致命的神经毒素,建立检测其含量的灵敏快捷方法对日常环境监测非常重要.提出采用金微电极微分脉冲伏安法直接测定甲基汞,对其进行电化学分析,并与玻碳电极测定法进行比较.研究结果表明: 在相同实验条件下,金微电极对甲基汞的检测更加灵敏,其最低检测质量浓度为 0.10 μg/L.在最优实验参数(pH=5.0、沉积电位为-0.80 V、沉积时间为800 s)下,金微电极对甲基汞质量浓度检测的线性范围为 0.05~0.50 μg/L,灵敏度为 0.354 nA/(μg·L),最低检测限为 0.012 μg/L,远低于世界卫生组织的检测标准值(1.0 μg/L).基于金微电极构建的电化学传感器对甲基汞表现出良好的选择性,具有操作简单、检测限低、稳定性高及抗干扰性能好等优点,为甲基汞的痕量检测提供了新的平台.
Methylmercury is a kind of fatal neurotoxin. It is of great importantance to establish a sensitive and rapid method to detect its content for the daily environmental monitoring. We propose a new method for direct determination of methylmercury by the differential pulse voltammetry with gold microelectrode and analyze the electrochemical behavior of methylmercury by this method. Meanwhile, we conduct comparative experiments by the differential pulse voltammetry with glassy carbon electrode. The results show that under the same experimental conditions, the gold microelectrode is more sensitive to methylmercury, and its minimum detection concentration reaches 0.10 μg/L. Under the optimal experimental parameters(pH=5.0, deposition potential of -0.80 V and deposition time of 800 s), the linear range of methylmercury concentration detection by the gold microelectrode method is 0.05- 0.50 μg/L, the sensitivity is 0.354 nA/(μg·L), and the minimum limit of detection is 0.012 μg/L, which is far lower than the standard detection value given by the World Health Organization(1.0 μg/L). In addition, the electrochemical sensor based on gold microelectrode shows good selectivity for methylmercury with the advantages of simple operation, low detection limit, high stability and good anti-interference performance. The gold microelectrode method provides a new platform for the trace detection of methyl mercury.
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