Ultrasensitive label-free electrochemiluminescence immunosensor based on N-(4-aminobutyl)-N-ethylisoluminol-functionalized graphene composite  

作　　者：Jiangnan Shu Wen Shen Hua Cui 

机构地区：[1]CAS Key Laboratory of Soft Matter Chemistry [2]Department of Chemistry, University of Science and Technology of China

出　　处：《Science China Chemistry》2015年第3期425-432,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(20625517,21075115,21173201);the Merieux Research Grants,the Fundamental Research Funds for the Central Universities(WK2060190007);the Opening Fund of the State Key Laboratory of Electroanalytical Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences(SKLEAC201408)

摘　　要：The electrochemiluminescence(ECL) behavior of N-(4-aminobutyl)-N-ethylisoluminol(ABEI)-functionalized graphene composite(ABEI-GC) modified on an indium tin oxide(ITO) electrode was studied. ABEI-GC exhibited excellent ECL activity. On this basis, a label-free ECL immunosensor was developed for the sensitive detection of human immunoglobulin G(h Ig G) by using ABEI-GC as the ECL nano-interface via a layer-by-layer assembly technique. ABEI-GC was first assembled onto an ITO electrode. Positively charged chitosan was then electrostatically adsorbed to the modified electrode. Finally, negatively charged antibody-coated gold nanoparticles were attached to the surface to form the ECL immunosensor. In the presence of h Ig G, h Ig G was captured by its antibody. In addition, an ECL signal was detected in the presence of H2O2 when a double potential was applied. The ECL immunosensor for the determination of h Ig G showed a linear range of 1.0×10-13–1.0×10-8 g/mL with a detection limit of 5.0×10-14 g/m L. This immunosensor has high sensitivity, wide linearity and good reproducibility. The superior sensitivity of the proposed ECL immunoassay mainly derives from the incorporation of ABEI-GC, which not only improves the ECL intensity, response speed, and stability, but also provides a large specific surface for high levels of protein loading. This work reveals that ABEI-GC is good nano-interface for the construction of ECL biosensors. Our strategy is promising for protein detection and may open up a new avenue for ultrasensitive label-free immunoassays.The electrochemiluminescence（ECL） behavior of N-（4-aminobutyl）-N-ethylisoluminol（ABEI）-functionalized graphene composite（ABEI-GC） modified on an indium tin oxide（ITO） electrode was studied. ABEI-GC exhibited excellent ECL activity. On this basis, a label-free ECL immunosensor was developed for the sensitive detection of human immunoglobulin G（h Ig G） by using ABEI-GC as the ECL nano-interface via a layer-by-layer assembly technique. ABEI-GC was first assembled onto an ITO electrode. Positively charged chitosan was then electrostatically adsorbed to the modified electrode. Finally, negatively charged antibody-coated gold nanoparticles were attached to the surface to form the ECL immunosensor. In the presence of h Ig G, h Ig G was captured by its antibody. In addition, an ECL signal was detected in the presence of H2O2 when a double potential was applied. The ECL immunosensor for the determination of h Ig G showed a linear range of 1.0×10^-13–1.0×10^-8 g/mL with a detection limit of 5.0×10^-14 g/m L. This immunosensor has high sensitivity, wide linearity and good reproducibility. The superior sensitivity of the proposed ECL immunoassay mainly derives from the incorporation of ABEI-GC, which not only improves the ECL intensity, response speed, and stability, but also provides a large specific surface for high levels of protein loading. This work reveals that ABEI-GC is good nano-interface for the construction of ECL biosensors. Our strategy is promising for protein detection and may open up a new avenue for ultrasensitive label-free immunoassays.

关 键 词：N-（aminobutyl）-N-（ethylisoluminol）（ABEI） GRAPHENE electrochemiluminescence immunosensor 

分 类 号：O657.1[理学—分析化学] TP212[理学—化学]