STUDIES ON THE EFFECT OF STORAGE ON THE PURITY OF SODIUM IODIDE-I1311

Abstract

Solutions of NaI131 upon storage show the presence of several bands (usually six inclusive of NaI131) when chromatographed one dimensionally in an ascending technique with various solvent mixtures and radioautographed. The percentage of radioactivity in the bands other than NaI131 increases rapidly upon storage at room temperature. Incubation of NaI131 solutions under nitrogen for 1 1/2 hours with 40 mg./ml. of cysteine at pH 4 pH 7 or 10 mg./ml. of NaI127 or KI127 at pH 7 converges the extraneous bands into the NaI131 are due to oxides of iodine or due to iodides other than NaI131. Studies on the uptake of the NaI131 or the major extraneous band by day old chick thyroids indicate that 20% of the injected radioactivity of the extraneous band is collected in the thyroid in contrast to the 60% uptake of NaI131.