Cyclotron isotopes and radiopharmaceuticals—XXII. Improved targetry and radiochemistry for production of 123I and 124I☆

Abstract An improved 4 π water-cooled target for production of 123 I of >99.4% radionuclidic purity via the 124 Te( p ,2 n ) 123 I reaction with 25.8-MeV protons on 256 mg cm −2 124 Te of >99.8% isotopic enrichment is described. Radiochemical methods and results for obtaining 123 I as iodide by sorption techniques, and a quantitative procedure for recovery (99.8 ± 0.2%) of the ultrahigh enrichment 124 Te are described. The methods are applicable to 124 I production if the incident proton beam is reduced to 12 MeV. Optimized thick target production yields for 123 I and 10.6 and 0.093 mCi μAh −1 , respectively.