基于双层酶信号放大及纳米功能界面的微囊藻毒素电化学免疫传感器  

Electrochemical Immunosensor for Microcystin-LR Detection Based on Nano-composite Material Immobilization and Enzymatic Amplification

作　　者：尹艳艳[1,2] 侯丽 张丽丽 林学滨[1,2] 吴晓苹 YIN Yan-Yan;HOU Li;ZHANG Li-Li;LIN Xue-Bin;WU Xiao-Ping(Key Laboratory of Analytical Science of Food Safety and Biology(Ministry of Education&Fujian Province),College of Chemistry,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]福州大学食品安全与生物分析教育部重点实验室,福州350108 [2]福州大学化学学院,福州350108

出　　处：《分析化学》2018年第4期493-501,共9页Chinese Journal of Analytical Chemistry

基　　金：本文系国家自然科学基金项目(No.21375019)和教育部创新团队(二期)项目(No.IRT15R11)资助

摘　　要：设计了一种基于纳米复合膜双层酶信号放大的竞争型电化学免疫传感器,用于检测痕量微囊藻毒素-LR(Microcystin-(leucine-arginine),MCLR)。在多壁碳纳米管修饰玻碳电极上电沉积金纳米粒子形成纳米复合膜,作为MCLR抗体(anti-MCLR)和辣根过氧化物酶(HRP)的固定化载体;引入HRP作为封闭剂或者通过抗体捕获HRP标记的MCLR(HRP-MCLR),起封闭活性位点及协同催化的作用。利用MCLR与HRPMCLR对纳米复合膜所固载抗体活性位点的竞争结合模式,采用微分脉冲伏安法(DPV)测定电极界面上HRP酶催化过氧化氢(H_2O_2)氧化对苯二酚(HQ)产生的还原电流,实现MCLR的定量检测。此传感器具有良好的特异性、稳定性与灵敏度,线性检测范围为0.1~100.0 μg/L,检出限为0.038 μg/L(S/N=3),对实际水样的加标回收率为72.9%~117.3%。A competitive electrochemical immunosensor based on the nano-composite material immobilization and enzymatic amplification was designed for detection of microcystin-LR.Gold nanoparticles/carboxylated multi-walled carbon nanotubes(AuNPs/c-MWCNTs)composite film,which formed by electrodepositing of AuNPs on the C-MWCNTs modified glassy carbon electrode,was used for the immobilization of the antibody of microcystin-LR(anti-MCLR).Horseradish peroxidase(HRP)was introduced onto the nanocomposite interface by HRP blocked sensing interface and specific capture of antibody with target.It could be employed to catalyze the reduction of H 2O 2,and to block the possible remaining active sites as well.A competitive immunoreaction between antigen and MCLR-HRP was used for target analysis.In the presence of H 2O 2 and hydroquinone(HQ),MCLR could be indirectly detected with differential pulse voltammetry(DPV)method by determining the reduction current of HQ.Under the optimal conditions,the proposed immunosensor exhibited wide linear ranges in the concentration ranges of 0.1-100.0μg/L,with a detection limit of 0.038μg/L(S/N=3,n=8).The immunosensor showed good specificity,stability and sensitivity.It was used to determine MCLR in real water samples with the recoveries of 72.9%-117.3%.

关 键 词：辣根过氧化物酶 多壁碳纳米管 纳米金 微囊藻毒素 电化学免疫传感器 

分 类 号：O657.1[理学—分析化学]