The determination of rat IgE is carried out as direct sandwich ELISA. An antibody specific for rat IgE has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any IgE present is bound. After washing away any unbound substances, an enzyme-linked antibody is added. Following a wash, a substrate solution is added to the wells and color develops in proportion to the amount of antibody conjugate. The absorption at 450 nm is proportional to the IgE con cen tration. Sample Types: serum, biological fluids. Range: 15.6 - 50 ng/ml. Sensitivity: 15.6 ng/ml (sample dilution 1:10). Time: 4.5 hours ? The Eagle Biosciences Rat IgE ELISA Assay Kit is designed for the quantitative determination of IgE antibodies in rat serum and biological samples. The Rat IgE ELISA Assay Kit is for research use only and should not be used in diagnostic procedures.