Syntheses Of Immunogold Probe And Its Application In Immunoassay On Polyethylenimine Film

Gold nanoparticles show some unique properties, such as small-dimension-effect, surface effect,quantum size effect,etc. which due to their high area ratio,surface-energy and surface-activation,that make their catalytical,optical,electronical and biological applications promising and make them an ideal candidate for nano-material preparation and nano-device fabrication.This thesis reports the synthesis of gold nanoparticles with different dimensions via aqueous phase synthesis method from the initial raw material HAuCl4. Gold nanoparticles synthesized here are characterized by Transmission Electron Microscopy (TEM), UV-Vis Spectroscopy. In this thesis, a polyethylenimine (PEI) film was formed on the quartz slides rather than APTMS coated film for more amines and safer. A method based on use of functionalized gold nanoparticles on polyethylenimine film has been developed for colorimetric detection of immunoglobulin G (IgG). The immunogold nanoparticles were immobilized on quartz slides by recognition between antibody and antigen, with the antigen chemically adsorbed on the polyethylenimine film. By measurement of the UV–visible spectra of the immobilized immunogold, detection of h-IgG was achieved. The detection limit for h-IgG by use of this method can be as low as 0.01μg·mL?1. This method is quite promising for numerous applications in immunoassay.