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...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.展开更多
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)
文摘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.
