Enzyme immunoassays (EIA) of Eicosanoids

Radioimmunoassay (RIA) and enzyme immunoassay (EIA) are used for detecting very small amounts of a hormone, drug, or other such material in blood (serum), tissue, urine, or culture media. Both radioimmunoassay and enzyme immunoassay techniques for the measurement of eicosanoids are based on the principles of the competitive substrate binding assay. More specifically, these assays involve the competition (for binding sites on an antibody) of a known concentration of a labeled eicosanoid with an unknown quantity of the same unlabeled eicosanoid. The antibody used has been generated against the specific eicosanoid to be measured. EIA is similar to RIA as an assay except that instead of using a radiolabeled compound, the competing antigen is labeled with a specific enzyme.