Abstract: A swab device, method, and kit for collecting and analyzing a sample for an analyte (antigens or antibodies) on the swab. The device includes a narrow rod or stick-like support in combination with an assay medium which is positioned adjacent to the support. The assay medium is extended longitudinally down the support a length sufficient to permit an immunoassay to be carried out within it. The assay medium and the support may include a capillary medium. A collection medium may also be attached to the capillary medium to enhance sample collection. The method includes collecting a sample suspected of containing the analyte in a sample collection area at the end of the swab. A liquid containing a labelled component is applied to the swab and allowed to immunochemically react with the sample. If the analyte is present, an immunocomplex is formed and retained on the swab. A wash solution is subsequently applied to the swab to effect the separation of the immunocomplex from excess free label.

Abstract: A sensitive direct immunoassay system is provided for the detection of an antigen in body fluids. A single antibody which reacts with an antigen or antigens and which is bonded to an insoluble member, is incubated with a test sample. During this first period of incubation a portion of an antigen present in the test sample will combine with the antibody immobilized on the insoluble member. The antibody bonded member, to which antigen is attached, is then washed and incubated with an enzyme tagged antibody reagent. During the second incubation, the tagged antibody reacts with antigen fixed to the antibody member in the first incubation. Thus, an immobilized "sandwich" is formed of an insoluble member- antibody-antigen-enzyme tagged antibody. After the second incubation, the member is washed again to remove unreacted enzyme antibody reagent. The member is then exposed to a substrate which is converted by the enzyme to produce an end product.