欢迎访问《茶叶科学》,今天是

茶叶科学 ›› 2011, Vol. 31 ›› Issue (6): 485-492.doi: 10.13305/j.cnki.jts.2011.06.002

• • 上一篇    下一篇

MWCNTs-IL-SPCE传感器检测茶叶中痕量铅研究

徐旭明, 窦文超, 赵广英*   

  1. 浙江工商大学食品与生物工程学院,浙江省食品安全重点实验室,浙江 杭州 310035
  • 收稿日期:2011-03-14 修回日期:2011-07-18 出版日期:2011-12-15 发布日期:2019-09-09
  • 通讯作者: zhaogy-user@163.com
  • 作者简介:徐旭明(1986— ),男,浙江建德人,硕士研究生,主要从事电化学检测重金属的研究。
  • 基金资助:
    国家自然科学基金(No.30571623)、浙江省重中之重学科(No.Z05-29)、浙江工商大学校级创新基金(No.1110XJ1710139)、浙江工商大学新苗人才项目(No.3070JQ4111087G)

Multi-walled Carbon Nanotubes-Ionic Liquid Modified Screen-printed Carbon Electrodes for the Determination of Trace Lead in Tea

XU Xu-ming, DOU Wen-chao, ZHAO Guang-ying*   

  1. Food safety lab of Zhejiang Province, College of Food Science and Biotechnology Engineering, Zhejiang Gongshang University, Hangzhou 310035, China
  • Received:2011-03-14 Revised:2011-07-18 Online:2011-12-15 Published:2019-09-09

摘要: 研究构建了一种新型、高灵敏性和高选择性的电化学传感器,结合差分脉冲溶出伏安法快速检测茶叶样品中的痕量铅。采用超传导性粘结剂离子液体1-丁基-3-甲基咪唑六氟磷酸盐([BMIM]PF6)和功能化的多壁碳纳米管(MWCNTs)修饰丝网印刷碳电极,提高了电极表面的导电性和信号转换。在含0.006mol/L I, pH4.5的NaAc-HAc缓冲液中,Pb2+在–1.1V沉积电位下吸附于MWCNTs-IL-SPCE膜上,当正电压扫过时,铅氧化溶出,在–0.30V下出现一个很好的溶出峰,低浓度的I¯明显增强了铅的溶出峰电流。溶出峰高值与Pb2+浓度在2~600μg/L范围内呈线性关系,相关系数为0.99926,检测限为0.63μg/L。试验结果与ICP-MS测定值进行t检验,无显著性差异。该方法灵敏、稳定,可用于茶叶中痕量铅简单、经济的检测。

关键词: 多壁碳纳米管, 离子液体, 丝网印刷碳电极, 茶叶,

Abstract: A new, high sensitivity and selectivity electrochemical sensor for determination of trace lead in tea by differential pulse stripping voltammetry was investigated. For modification of the screen-printed carbon electrode, 1-butyl-3-methylimidazolium hexafluorophosphate was applied as a super conductive binder and multi-walled carbon nanotubes were used after being functionalized. They improved the conductivity and signal transduction of electrode surface. In pH4.5 NaAc-HAc buffer containing 0.006mol/L I¯, Pb2+ adsorbed onto the surface of MWCNTs-IL film coated SPCE at the deposition potential of –1.1V. During the positive potential sweep, lead was oxidized, and a good stripping peak appeared at –0.30V. Low concentration of I¯ significantly enhanced the stripping peak current of lead. The liner relationship between stripping peak value and concentration of Pb2+ was in the range of 2~600μg/L with the R value of 0.99926 and detection limit of 0.63μg/L. No significant difference existed after the detection results were compared with ICP-MS method using t test. The high sensitivity and stability of this method demonstrated the application for a simple and economical determination of trace lead in tea.

Key words: multi-walled carbon nanotubes, ionic liquid, screen-printed carbon electrode, tea, lead

中图分类号: