Construction Of Flow Injection Chemiluminescence Immunosensor Based On Enzyme Amplification And Its Application In Banned Food Additives

Flow injection analysis(FIA) is rapid and high automation. Chemiluminescent immunoassay(CLIA) possesses typical merits of high sensitivity, good specificity and wide linear range. FI-CLIA is the combination of the two technologies and combines their advantages. FI-CLIA has been favored by many researchers and widely applied in many fields. In this paper, we use novel carboxylic resin beads as solid carrier, and introduce HRP/enzyme labeled antibody or silica nanocomposite into the immunosensor, then establish the enzymatic amplifying chemiluminescence immunoassay for beta receptor agonist agent salbutamol and brombuterol, respectively. This method would have intriguing application prospect in the detection of illegal food additive residues and other small molecules.The dissertation includes four chapters:In chapter l, the research background and significance of the thesis are introduced. And the related flow injection technique, the basic theory and the type of chemiluminescence immunoassay, common chemiluminescence system and immobilized carrier for FI-CLIA has been described.In chapter 2, a simple, rapid and sensitive flow injection chemiluminescence immunoassay was developed for the determination of salbutamol(SAL) based on carboxylic resin beads and HRP enzyme-amplification. Resin beads with carboxyl groups were creatively employed as supports for immobilizing more coating antigen through amide bonds. Then, the second antibody labeled with HRP was introduced, and an enzyme-enhanced CL emission was obtained due to the catalytic activity of HRP for the luminol-PIP-H2O2 reaction. Compared with other methods, this immunosensor for detecting salbutamol had a wider linear range, lower detection limit and examined in real samples with favorable results.In chapter 3, in order to achieve CL signal amplification, we prepared the silica nanoparticles with good dispersion and uniform particle size. Then the silane coupling agent(APTES) and glutaraldehyde(GA) were used to modify Si O2 surface for loading horseradish peroxidase(HRP) and antibody(Ab). The prepared materials were characterized by means of Fourier transform infrared spectroscopy(FT-IR), transmission electron microscopy(TEM) and scanning electron microscopy(SEM).In chapter 4, the above prepared HRP-Si O2-Ab composite was used for FI-CLIA, since a lot of HRP was loaded, the system achieved enzymatic amplifying CL signal, and improved the analytical sensitivity. This immunosensing strategy was first used in the detection of brombuterol and would be of great value in enriching the nanoparticles-based CLIA application range.