摘要
建立基于核酸酶安培型电化学生物传感器的示差脉冲伏安法测定纺织品中铅的含量。信号探针集成的核酸酶17E DNAzyme铅离子识别体系组装在金纳米粒子修饰的金基底电极上,同时作为生物识别元件和信号元件。采用三电极体系,以0.1 mol/kg的NaClO_4溶液为电解质溶液。调整时间为50 ms,间隔时间为0.5 s,调制振幅为50mV,阶跃电势为5 mV,扫描范围为0.15～0.55 V,采用示差脉冲伏安法测定铅离子。铅离子的质量浓度c在0.020～2.0μg/kg范围内,其对数lgc与电极峰电流信号的变化率(I_0–I)/I_0呈良好的线性关系,线性相关系数为0.992 4,方法检出限(S/N=3)为1.3μg/kg。测定结果的相对标准偏差为2.5%～4.0%(n=6),加标回收率为91.4%～105.3%。该方法与国标法的测定结果无显著性差异。该传感器对铅离子的检测具有良好的选择性,实现了对溶液中铅离子的无试剂化检测。该方法操作简便,准确度高,可用于纺织品铅含量的检测。
A method for determination of lead in textiles by differential pulse voltammetry(DPV)based on amperometric electrochemical biosensor of nuclease was established.Signal probe integrated 17E DNAzyme system was assembled on the gold nanoparticles functionalized gold substrate electrode as biological recognition element and signal element.A three-electrode system was used with 0.1 mol/kg NaClO 4 solution as electrolyte solution.The adjustment time was 50 ms,the interval time was 0.5 s,the modulation amplitude was 50 mV,the step potential was 5 mV,and the scanning range was 0.15-0.55 V.The lead iou in textiles was determined by DPV.In the range of 0.020-2.0μg/kg of lead ion mass concentration(c),the lg c of lead ion had a good linear relationship with the change rate of DPV peak current signal(I 0-I)/I 0.The linear correlation coef fi cient was 0.992 4,and the detection limit(S/N=3)was 1.3μg/kg.The relative standard deviations were 2.5%-4.0%(n=6),and the recoveries were 91.4%-105.3%.There was no significant difference between this method and the national standard method.The sensor has good selectivity for the detection of lead ion and achieves reagent-free detection of lead ion in solution.The method is simple,accurate and can be used for the determination of lead content in textiles.
作者
洪华
王红卫
张爱平
申晓萍
任凤云
刘沙
HONG Hua;WANG Hongwei;ZHANG Aiping;SHEN Xiaoping;REN Fengyun;LIU Sha(Nantong Customs,Nantong 226004,China)
出处
《化学分析计量》
CAS
2019年第2期30-34,共5页
Chemical Analysis And Meterage
基金
南京海关(原江苏出入境检验检疫局)科技计划项目(2017KJ28)
