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This is a video about Competitive -ELISA Kit.
The micro ELISA plate provided in this kit has been pre-coated with a specific antigen. During the reaction, the antigen in samples or Standard competes with a fixed amount of the antigen on the solid phase supporter for sites on a biotinylated detection antibody specific for antigen. Excess conjugate and unbound sample or standard are washed from the plate, and Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. Free components are washed away. The substrate solution is added to each well. Only those wells that contain antigen, biotinylated detection antibody and Avidin-HRP conjugate will appear blue in color. The enzyme-substrate reaction is terminated by the addition of a sulphuric acid solution and the color turns yellow. The optical density (OD) is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm. The OD value is inversely proportional to the concentration of antigen. You can calculate the concentration of antigen in the samples by comparing the O.D. of the samples to the standard curve.