Detection reagent, article, and immunoassay method

摘要

The binding site on an immunoglobulin for a protein is blocked by hydrophobically coupling the immunoglobulin to a blocking agent such as a label. This results in a detection reagent useful in a variety of test assays in which a protein and an immunoglobulin are advantageously used together, but separately. The reagent is useful in the simultaneous determination of IgG and one of IgA or IgM. Anti-IgA-IgG or anti-IgM-IgG is coupled to a hydrophobic label, particularly a pigment or dye, which label blocks the binding site on IgG for Protein A, and labeled Protein A is added.