The Construction And Application Of Electrochemiluminescence Immunosensor Based On Functional Nanomaterials

Electrochemiluminescence immunoassay(ECLIA) is the product of combining electrochemiluminescence with immunoassay. It has the advantage of good specificity, high sensitivity, wide linear range etc. Recently, new functional nanomaterials have attracted widespread attention in the field of ECLIA, and opened up a new road for ECLIA research and development. The new functional nanomaterials in ECL sensors mainly served as sensor interface modified material, biomolecules immobilization matrix and signal labels and so on. In this paper, graphene enriched and immobilized quantum dots, and gold nanoparticles labeled horseradish peroxidase to detect mercury ions. Gold nanoparticles functionalized Zn O nanorods acted as matrix to immobilization coating antigen, and PAMAM-graphene labeled quantum dots severed as signal markers to detect the residue of brombuterol in food. Super paramagnetic Fe3O4 prepared by co-precipitation modified the interface of sensor.The dissertation includes four chapters:In chapter 1, the background knowledge and significance of this dissertation have been introduced with the emphasis on the following aspects, mechanism of ECL and functional nanomaterials, electrochemical immunosensor in real-life applications.In chapter 2, PDDA functionalized graphene, grapheme-quantum dots composite and gold nanoparticles-labeled horseradish peroxidase were synthesized, and characterized by UV-Vis absorption and High-resolution transmission electron microscopy(HRTEM). The above-mentioned functional materials were assembled to form an ultrasensitive electrochemiluminescence sensor for the detection of mercury ions. The immunosensor exhibited good reproducibility and stability with a low detection limit of 0.06 ng/m L.In chapter 3, gold nanoparticles-functionalized Zn O nanorods modified the electrode by electrostatical, and provided a larger platform for antigen, which reacted with the limited binding sites of the PAMAM-GO-QDs-antibody. We developed a sensitive electrochemiluminescence sensor for detection of brombuterol. New functional materials of Zn O nanorods and PAMAM-graphene improved the sensitivity of the sensor, and enriched electrochemiluminescence immunoassay applications based on nanoparticles.In chapter 4, super paramagnetic Fe3O4 prepared by co-precipitation could catalyze the decomposition of H2O2 to achieve quenching of the electrochemical signal. Fe3O4 nanoparticles were first used to catalyze the decomposition of H2O2, a co-reaction of quantum dots. A new type of quenching electrochemical immunosensor would be established.