Enzyme immunometric assay for quantitative determination of prostate specific antigen (PSA) in human serum or plasma
The prostate is a male sex gland. It produces a thick fluid that forms part of the semen. The prostate is about the size of a walnut. It is located below the bladder and in front of the rectum. The prostate surrounds the upper part of the urethra, the tube that empties urine from the bladder. The prostate needs male hormones to function. The main male hormone is testosterone, which is made mainly by the testicles. Some male hormones are produced in small amounts by the adrenal glands.
The DIAKEY PSA ELISA is a solid-phase, non-competitive immunoassay based upon the sandwich technique. Two different monoclonal anti-PSA antibodies are used. One antibody is coated on solid phase (coated plate), the other, specific for the PSA and labeled with HRPO, is used as a conjugate. The conjugate antibody and the coated antibody react simultaneously with the PSA antigen present in the standards, control serum and samples. Unbounded material is removed by a washing step. After washing, substrate reagent is added to each well and the enzyme reaction is allowed to proceed. During the enzyme reaction a blue color will develop if antigen is present. The intensity of the color is proportional to the amount of PSA present in the samples. The color intensity is determined in a microplate spectrophotometer at 450nm (reference 620nm).