RADIOIMMUNOASSAY WITH ANTIBODY-COATED DISCS AND TUBES

Abstract

ABSTRACT The measurement of polypeptide hormones by radioimmunoassay has been facilitated by the introduction of solid-phase antibody preparations which permit the separation of bound and free tracer to be performed by a rapid washing step. The solid-phase radioimmunoassay technique originally employed substituted powders as the solid-phase, and more recently, antibody-coated discs and tubes have been used. The observation that standard plastic tubes would adsorb an appropriate quantity of antibody for use in radioimmunoassay has allowed the development of an extremely simple method, in which the assay is performed in plastic counting tubes coated with specific antibody. Antibody-coated tube assays have been established for the measurement of HGH, HCS, HLH, ovine LH, ovine prolactin and other hormones. Recent observations on the use of coated-tube assays for the estimation of gonadotrophic hormones in human and ovine plasma are described, and the temporal relationship between oestrogen secretion and LH release is presented. The coated-tube assay procedure is simple, rapid and reliable, and is of general application to the assay of ligands such as antigens, steroids and other molecules with specific binding proteins.