A novel electrochemical impedance sensor based on DNAzyme was developed for highly sensitive detection of lead in textiles. Gold electrode modified by gold nanoparticles was used as substrate electrode and a novel DNAzyme was used as biological recognition element of lead ions,a new electrochemical impedance sensor for selective detection of lead ions with high sensitivity was built. Under the optimized conditions,the sensor could detect lead ions in solution with good linearty in the range of 1.0μg/L-10 mg/L with a low detection limit of 0.6μg/L. The recovery was 93.5%-106.0%,and relative standard deviation was not more than 5.4%(n=6). No significant difference was obtained between the results of theproposed method and the national standard method. The method was suitable for rapid determination of lead content in textiles on site with good selection.%建立一种基于核酸酶的电化学阻抗传感器检测纺织品中铅含量的方法.采用金纳米粒子修饰的金电极作为基底电极,以一种新型的核酸酶17E DNAzyme体系作为铅离子的生物识别元件,构建了一种新型的电化学阻抗传感器用于高灵敏选择性检测铅离子.在最佳实验条件下,传感器对溶液中铅离子的线性检测范围为1.0μg/L~10 mg/L,检出限为0.6μg/L.测定结果的相对标准偏差小于5.4%(n=6),加标回收率在93.5%~106.0%之间.采用该法对实际纺织品样品进行测试,并与国标方法测定值进行对比,实验结果表明两种方法的测定值无显著性差异.该方法操作简便,对铅离子的检测具有良好的选择性,可用于现场样品的在线、快速测定.
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