Immunoradiometric Assay for quantitative determination of thyroglobulin in human serum
The present method is based upon two anti-Tg monoclonal antibodies recognizing two different epitopes of the molecule. One antibody is adsorbed to the solid phase (coated tube), the other – labeled with iodine 125 is used as tracer. The sample to be tested is first incubated in the coated tube. Following this incubation and after an aspirating / washing cycle, the labeled antibody is added to each coated tube, where it is bound to the solid phase by means of the antigen in the standards and (if present) in samples. The amount of binding will be directly proportional to the antigen concentration. After tracer incubation, another washing / aspirating cycle will remove any liquid reagent residue. The radioactivity in the tubes is measured in a gamma counter.
The RIAKEY PSA IRMA Tube II is an one step non-competitive immunoradiometric (IRMA) method (“sandwich”). The method employs two highly specific monoclonal anti-PSA antibodies which recognize two different epitopes of the molecule. One antibody is coated on solid phase (coated tube), the other, specific for the PSA and labeled with Iodine-125, is used as a tracer. Antibody-coated polystyrene tubes serve as solid phase. The tracer 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. The amount of bound tracer will be directly proportional to the PSA antigen concentration and the remaining radioactivity bound to the tubes is measured in a gamma scintillation counter.