Abstract: A generic signaling assay method comprising an affinity matrix for the detection of low molecular weight compositions is provided. A test sample is mixed with a pre-determined amount of a substance conjugated to at least two molecules of the target analyte. When the test sample containing the multiple-analyte conjugated substance is passed over the immunoaffinity column, the antibodies can bind competitively to two species: free analyte and multiple-analyte conjugated substance. The column is then exposed to a second tagged antibody. Upon elution, high label activity is seen in a clean sample. Conversely, only a small amount of the label activity is detected in the eluant of a test sample that is highly contaminated with the free analyte.