Development of a simple and rapid antibody immobilization procedure for immunoradiometric assay of FSH and HCG

Choice of suitable solid phase separation system is an integral part of the immunoradiometric assay (IRMA) procedure. Antibody immobilized plastic tubes are the most preferred because of its extreme simplicity. Of the various methods studied for immobilization (coating), physical adsorption is observed to be reliable and convenient. Important factors towards immobilization of antibody viz. quality of plastic surface, concentration of antibody, optimum pH and incubation time were studied as the part of the standardization procedure. In order to increase the shelf life of the antibody coated tubes, efficacy of different stabilizers have been analyzed. Developed procedure was well adapted for developing coated tube immunoradiometric assay for FSH and HCG with comparable assay features as that of other commercial kits. The physical adsorption method developed is indeed a simple, convenient and rapid (overnight) method suitable for automation and large-scale production of IRMA kits. (author)