An Application of Thin-Layer Chromatography to Radiochemical Inspection of Iodide-131I and Sulfite- 35S

Abstract Thin-layer chromatography was applied to radiochemical purity determination of sulfites (35SO2-3) and iodides (131)I−), in which the samples were chromatographed on silica gel sheet with acetone-water mixture as solvent. Prior to actual application, certain compounds of S and I contained as impurities in the (35SO2-3) and (131)I− were chromatographically separated. The Rf values were determined as function of the concentration of the acetone solvent and of the concentration of the species in the sample solutions. Acetone was found to be a very effective solvent, only requiring the ratio of mixture with water to be changed to yield the Rf value of any compound, thus permitting the selection of a wide variety of solvent composition according to the combination of compounds to be developed. The solvent composition also influenced the developing time, which furnished another criterion in selecting the solvent composition. The Rf value was also greatly affected by the concentration of the species to b...