Question

The biochemical procedure used to detect human chorionic gonadotropin (hCG) is

• A. WIDAL
• B. CAT
• C. MRI
• D. ELISA

Answer 1

The correct option is D ELISA

The enzyme-linked immunosorbent assay (ELISA) is a medical test that uses antibodies and colour change to identify a substance. Home pregnancy test utilizes the principle of ELISA (sandwich enzyme immunoassay), with a unique mono-mono antibody combination specific against hCG present in urine/serum. The patient's urine/serum specimen is allowed to react with the monoclonal antibody directed against hCG, coated on the microtiter wells and the monoclonal antibody - enzyme conjugate complex. If hCG is present in the test specimen, antibody-hCG-antibody enzyme complex will be formed on the surface of the microtiter well. Washing the well under running tap water will clear off the unbound complex and the unreacted conjugate. Incubating the well with substrate reagent results in the development of blue colour. The intensity of the blue colour is proportional to the concentration of hCG present in the urine/serum specimen.