SANDWICH IMMUNOASSAY AND REAGENT THEREFOR

PROBLEM TO BE SOLVED: To measure the quantity of antigen existing in a sample by using IgY, a hen's egg antibody, as a solid phase antibody (primary antibody), using IgG as a secondary antibody, and using material simultaneously having a labeled part and a part with binding ability to the Fc area of IgG. SOLUTION: A hen's egg antibody is used as a solid phase antibody (primary antibody), and immunoglobulin is extracted and separated to obtain IgY. Animal IgG is used as a secondary antibody forming a sandwich. The secondary antibody can be polyclonal or monoclonal. In order to measure the quantity of the secondary antibody, IgY, antigen, IgG and labeled polypeptide which are material combining a labeled part and a part with binding ability to the Fc area of immunoglobulin, desirably polypeptide, are reacted in a water medium, and pH and reaction temperature are selected according to the sort of enzyme. After reaction, B/F separation is performed to eliminate unbound components, and then the quantity of the reacted secondary antibody is measured.