An enzyme immunoassay for the quantitative measurement of total human chorionic gonadotropin (hCG and b-hCG) in serum.
Chorionic Gonadotropin (hCG) is a glycoprotein hormone which is normally produced by the placenta during pregnancy. After conception, the hCG concentration increases rapidly to reach a peak near the end of the first trimester. High concentrations are observed throughout pregnancy. After delivery, hCG levels fall rapidly and become undetectable after a few days. Structurally intact hCG molecules are composed of an alpha and a beta subunit. The alpha subunit is nearly identical to the alpha subunits of other glycoprotein hormones, such as Thyroid Stimulating Hormone (TSH), Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH): The differences in the beta subunit of the respective hormones account for their biological specificity and immunochemical distinctiveness. Monoclonal antibodies recognizing unique sites on the beta chain of the §-hCG/hCG molecule are essential for differentiation between hCG and LH, FSH and TSH. Specific assays for beta-hCG permit the early detection of pregnancy. In addition to the elevated hCG levels during pregnancy, high concentrations of §hCG/hCG may be associated with neoplasms of trophoblastic and nontrophoblastic origin such as hydatiform mole, chorionepithelioma, embryonal cell carcinoma,seminoma and many others.
The DRG _-HCG 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 [mouse] directed towards a unique antigenic site on a __HCG molecule. An aliquot of sample containing endogenous _-HCG and/or HCG is incubated in the coated well with enzyme conjugate, which is an anti- _-HCG antibody conjugated with horseradish peroxidase. After incubation the unbound conjugate is washed off. The amount of
bound peroxidase is proportional to the concentration of _-HCG/HCG in the sample. Having added the substrate solution, the intensity of color developed is proportional to the concentration of _-HCG/HCG in the sample.