Determination of Organic Iodine Compounds in Serum. III. Iodotyrosines in Normal Human Serum

Abstract

Column chromatographic fractionation of the ¹²⁷I compounds of normal human serum and plasma has failed to reveal detectable amounts of the thyroxine precursors monoiodotyrosine (MIT) and diiodotyrosine (DIT). Over 90 % of the serum proteinbound iodine appeared in the iodothyronine fraction. The detection of iodotyrosine-iodine at levels as low as 0.2 μg/100 ml serum is possible with the method described.