An enzyme immunoassay for the quantitative measurement of leptin in serum and plasma. The DRG Leptin ELISA Kit is a solid phase enzyme-linked immunosorbent assay (ELISA) based on the sandwich principle. The microtiter wells are coated with a monoclonal antibody directed towards a unique antigenic site on a Leptin molecule. An aliquot of patient sample containing endogenous Leptin is incubated in the coated well with a specific biotinylated monoclonal anti Leptin antibody. A sandwich complex is formed. After incubation the unbound material is washed off and a Steptavidin Peroxidase Enzyme Complex is added for detection of the bound Leptin. Having added the substrate solution, the intensity of colour developed is proportional to the concentration of Leptin in the patient sample.