一种高灵敏度检测4甲基咪唑的电化学阻抗传感器

李伟,  赵常志*

（青岛科技大学 化学与分子工程学院，山东 青岛 266042）

摘要：  以2,5二巯基1,3,4噻二唑、乙酰丙酮和MnCl2为原料，采用简单的水溶液反应合成了水溶性化合物Mn（HL）2(H2O)2（HL=2巯基5（乙酰丙酮硫噻二唑）），并将其自组装在金电极表面上，制备了一种新型的电化学阻抗传感器。利用该传感器对咪唑类化合物的选择性响应，实现了对可口可乐、百事可乐中的致癌物4甲基咪唑的高灵敏度测定。在优化的实验条件下，传感器的电荷转移电阻与500×10-5~200×10-3μg·L-1范围内的4甲基咪唑质量浓度呈线性关系，线性相关系数为0999 2，检出限为800×10-6μg·L-1，对实际样品测定的相对标准偏差（RSD）小于198（n=5），加标回收率为932%~952%。

关键词： 电化学阻抗传感器; 2,5二巯基1,3,4噻二唑; 4甲基咪唑; 可口可乐; 百事可乐

中图分类号： O 657.1               文献标志码： A

A Electrochemical Impedance Sensor for Highly Sensitive Detection of 4Methylimidazole

LI Wei,  ZHAO Changzhi

(College of Chemistry and  Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China)

Abstract： A watersoluble complex Mn（HL）2(H2O)2 （HL=2thiol5（acetylacetone）sulfurthiadiazole） was prepared based on simple reaction in aqueous solution by using 2,5dimercapto1,3,4thiadiazole, acetyl acetone and MnCl2 as raw material. And Mn（HL）2(H2O)2 was selfassembled on the gold electrode surface to prepare a novel electrochemical impedance sensor. As basis of the selective response of the sensor to imidazole compounds, the carcinogenic 4methylimidazole was determined in CocaCola and PepsiCola. Under the optimum conditions, the charge transfer resistances of the sensor were proportional to concentration of 4methylimidazole in 5.00×10-5—2.00×10-3 μg·L-1 range with a linear correlation coefficient of 0999 2, and the detection limit for 4methylimidazole was estimated to 8.00×10-6 μg·L-1. The relative standard deviation was less than 1.98 (n = 5) and the recovery was in the range of 93.2%—95.2% for the determination of actual samples.

Key words: electrochemical impedance sensor; 2,5dimercapto1,3,4thiadiazole; 4methylimidazole; CocaCola; PepsiCola

收稿日期： 20140303

作者简介： 李伟（1990—）,男，硕士研究生.               *通信联系人.