This Cysteinyl Leukotriene kit is a competitive immunoassay for the determination of Cysteinyl Leukotrienes in tissue culture media and urine. Please read the complete kit insert before performing this assay. The kit measures three of themajor metabolites of LTA ; LTC , LTD and LTE . The kit uses a monoclonal antibody to the Cysteinyl Leukotrienes (LTC , LTD and LTE ) to bind, in a competitive manner, the Cysteinyl Leukotrienes in the sample or an alkaline phosphatase molecule which has LTC covalently attached to it. After incubation at room temperature the excess reagents are washed away and substrate is added. After a second incubation, the enzyme reaction is stopped and the yellow color generated is read on a microplate reader at 405nm. The intensity of the bound yellowcolor is inversely proportional to the concentration of LTC in the standards or Cysteinyl Leukotrienes in the samples. The measured optical density of LTC is used to calculate the concentration of Cysteinyl Leukotrienes in the sample.