Separation of 201Tl and 203Pb by ion-exchange chromatography on AG 50W-X4 and Chelex 100, after proton bombardment of a thallium cyclotron target

A method is presented for the simultaneous preparation of 201Tl and 203Pb via proton induced nuclear reactions on natural thallium cyclotron targets and ion exchange chromatography. Lead radioisotopes are seperated from the thallium target material by cation exchange chromatography on AG50W-X4 in hydrobromic acid containing bromine. The lead radioisotopes are sorbed on the chelating ion exchanger, Chelex 100, and any remaining thallium is eluted with ascorbic acid. The resin column is left for 32 h to permit the 201Pb to decay to 201Tl, which is then eluted with ascorbic acid. The 203Pb is finally eluted with nitric acid. Separations are sharp and less than 1 μg of thallium remains in the final solutions. 3 figs., 3 tabs