APPLICATION OF THE COATED CHARCOAL SEPARATION METHOD TO THE RADIOIMMUNOASSAY OF PLASMA CORTICOTROPHIN

Abstract

A radioimmunoassay method for porcine plasma corticotrophin (ACTH) is described. The ACTH is extracted from plasma by adsorption to silicic acid powder and subsequent elution by an acetone-acetic acid mixture. The ACTH antiserum and 131I-labelled ACTH are added and the antigen-antibody reaction proceeds for 3 days. Activated charcoal coated with plasma is used to separate antibody-bound and unbound ACTH. Factors affecting the accuracy, sensitivity, and specificity of the assay have been assessed.