Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE) BioAssay-ELISA Kit (Human) employs the competitive inhibition enzyme immunoassay technique. An antibody specific for Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE) has been pre-coated onto a microplate. A competitive inhibition reaction is launched between Horseradish Peroxidase (HRP) labeled Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE) and unlabeled Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE) (Standards or samples) with the pre-coated antibody specific for Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE). After incubation the unbound conjugate is washed off. The amount of bound HRP conjugate is reverse proportional to the concentration of Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE) in the sample. After addition of the substrate solution, the intensity of color developed is reverse proportional to the concentration of Pro-Insulin Like Growth Factor II E-Peptide (IGFIIE) in the sample.