Adsorption of radioiodine on platinum: a fast and simple column method to obtain concentrated and pure radioiodide in either water or anhydrous solvents.

Radioiodine can be adsorbed on a small column filled with platinum powder from an acidified aqueous solution. The adsorption is nearly quantitative, irrespective of the oxidation state of the iodine used. With an alternated flow of hydrogen gas and solvent, the iodine can be desorbed from the platinum into an aqueous or organic solvent. Depending on the solvent used, the desorption process is also nearly quantitative, and the eluate obtained contains almost pure radioiodide. Using this method, labelling reactions with radioiodide are no longer restricted to water-stable substrates and catalysts.