Human Breast Cancer Antigen C A15-3 ELISA Kit
Human Breast Cancer Antigen CA 15-3 ELISA Kit is based on the principle of a solid phase enzyme-linked immunosorbent assay. The assay system utilizes a monoclonal antibody directed against a distinct antigenic determinant on the intact CA 15-3 molecule is used for solid phase immobilization (on the microtiter wells). A rabbit anti-CA 15-3 antibody conjugated to horseradish peroxidase (HRP) is in the antibody-enzyme conjugate solution. The test sample is allowed to react sequentially with the two antibodies, resulting in the CA 15-3 molecules being sandwiched between the solid phase and enzyme linked antibodies. After two separate 1-hour incubation steps at 37C, the wells are washed with Wash Buffer to remove unbound labeled antibodies. A solution of TMB Reagent is added and incubated for 20 minutes, resulting in the development of a blue color. The color development is stopped with the addition of Stop Solution changing the color to yellow. The concentration of CA 15-3 is directly proportional to the color intensity of the test sample. Absorbance is measured spectrophotometrically at 450 nm.