KE20021 is a solid phase sandwich Enzyme Linked-Immuno-Sorbent Assay (Sandwich ELISA). The rat IL-1 beta ELISA kit is to be used to detect and quantify protein levels of endogenous rat IL-1 beta. The assay recognizes rat IL-1 beta. An antibody specific for rat IL-1 beta has been pre-coated onto the microwells. The rat IL-1 beta protein in samples is captured by the coated antibody after incubation. Following extensive washing, another antibody specific for rat IL-1 beta is added to detect the captured rat IL-1 beta protein. For signal development, Streptavidin-HRP is added, followed by Tetramethyl-benzidine (TMB) reagent. Solution containing sulfuric acid is used to stop color development and the color intensity which is proportional to the quantity of bound protein is measurable at 450nm with the correction wavelength set at 630 nm.