基于金/石墨烯/C_(60)纳米复合材料为基质构建ECL传感器用于“signal off”模式中Pb^(2+)的检测  

A “signal-off” electrochemiluminescence sensor for Pb^(2+) based on the matrix of Au/Graphene/C_(60) nanocomposite

作　　者：邓炜[1,2] 余燕清 徐畅 祁乐[1] 苟桃吉 高明[1] 

机构地区：[1]重庆市三峡库区农业面源污染控制工程技术研究中心西南大学资源环境学院,重庆400715 [2]重庆市建设用地事务中心,重庆400015 [3]重庆市纳米材料及传感技术工程实验室西南大学化学化工学院,重庆400715 [4]重庆市烟草专卖局,重庆400023

出　　处：《化学传感器》2017年第1期52-59,共8页Chemical Sensors

基　　金："十二五"国家科技支撑计划项目(2012BAD14B18);中央高校基本业务费专项(XDJK2015D020)

摘　　要：该实验通过将分子内自增强的电致化学发光(ECL)钌复合物分子(PAMAM-Ru)直接标记到8-17DNAzyme底物链上,利用PAMAM-Ru分子内的相互作用及电子的快速传递,极大地提高了ECL试剂的发光效率及稳定性。另一方面,制备了纳米金功能化的石墨烯和C_(60)的复合物(Au@rGO-C_(60)),由于该纳米复合材料自身的比表面积较大,能够固载大量的8-17 DNAzyme酶链,使其与底物链结合形成Pb^(2+)特异剪切位点;同时由于Au@rGO-C_(60)纳米复合材料自身具有促进电子传递的作用,以其作为固载基质将实现信号的进一步放大。另外,S_2O_8^(2-)作为分子间共反应试剂与PAMAM-Ru分子内自增强作用相结合实现ECL信号的双重放大,获得较强的初始信号。当Pb^(2+)存在时,能够识别特异性的剪切位点,从而使结合到电极表面的PAMAM-Ru离开电极,导致ECL信号显著降低,因此构建了"signal off"型ECL铅离子传感器。其检测范围为1.0×10^(-15)mol/L到1.0×10^(-8) mol/L,检测限为3.34×10^(-16) mol/L。In this work, the intramolecular self-enhanced ECL molecule PAMAM-Ru was directly labeled with 8-17 DNAzyme substrate chain, which could greatly improve the luminous efficiency and stability of ECL reagents through intramolecular interactions and rapid electron transport. On the other hand, the Au nanoparticles functionalized graphene and C60complex（Au@r GO-C60） could act as matrix to immobilize a large amount of 8-17 DNAzyme enzyme chain via its large specific surface area. The 8-17 DNAzyme enzyme chain could be further hybridized with the 8-17 DNAzyme substrate chain to form Pb2＋-specific DNAzyme. Meanwhile, the Au@r GO-C60 as matrix could further amplify the ECL signal owing to its large specific surface area and desirable electrical conductivity. In addition, the double signal amplification was obtained by using S2O82-as intermolecular co-reaction reagent and PAMAM-Ru as intramolecular ECL luminophore, resulting in the generation of the strong initial signal.In presence of target Pb2＋, the ECL signal significantly decreased comparing with that in the absence of Pb2＋, which indicated that the PAMAM-Ru labeled 8-17 DNAzyme substrate chain was irreversibly self-cleaved to release PAMAM-Ru from the electrode surface. The prepared ＂signal off＂ ECL biosenesor was suuccesfully constructed,and the detection range was 1.0×10-15 mol/L to 1.0×10-8 mol/L, the detection limit is 3.34×10-16 mol/L.

关 键 词：8-17 DNAZYME “signaloff” PAMAM-Ru 分子间共反应试剂 Au@rGO-C60纳米复合材料 

分 类 号：TB33[一般工业技术—材料科学与工程] TP212[自动化与计算机技术—检测技术与自动化装置]