Dependence of quality of thallium-201 on irradiation data

Backgrounds: Thallium-201 is produced through 203Tl (p, 3n) 201pb 201Tl reaction by cyclotron. This radioisotope has known as one of the cyclotron radioisotopes which is used for myocardial perfusion in the coronary artery disease, Tl-201 after chemical purification and quality control in the form of 201Tl-chlorid is ready to send to the hospitals. Materials and methods: In this work the effect of the proton energy on quality of Tl-201, was studied. Radionucleidic purity was determined by high purity Ge (HPGe) detector Gamma spectrometer, in production time and after one half-life (73h). The targets were coated with Enriched Thallium-203 (97%). Results: The Variation of thickness of targets was 18.3 ± 1.3µm. The different energies of bombardment on quality of Tl-201 and Tl-200, Tl-202, and Pb-203 (as impurity) were studied. The results have shown that optimum energy for proton was 28.5 MeV. Conclusion: The variation energy of bombardment can change the purity of Tl-201 but all results were in the standard range according to the United States Pharmacopoeia (USP) and European Pharmacopoeia. Iran . J. Radiat. Res. 2003 1(1): 51 - 54.