Evaluation of a Simplified Technique for the Specific Measurement of Serum Thyroxine Concentration

Abstract

A simple, highly reproducible, and accurate method for the specific measurement of thyroxine in serum is described. This method depends upon the competitive protein-binding principle developed by Murphy and Pattee, but the method appears to be far simpler and more convenient than other methods based upon this principle. The results obtained by the present method and by a standard Murphy-Pattee technique in various clinical states are essentially indistinguishable, are not influenced by iodine containing compounds, accurately diagnose the presence of hyperthyroidism or hypothyroidism, and are affected in the expected manner by changes in the activity of the thyroxine-binding proteins.