PRODUCTION OF BR-76 BY A LOW-ENERGY CYCLOTRON

We present a production method of a positron-emitting bromine isotope Br-76 (T-1/2 = 16.2 h) using a low-energy proton reaction Se-76(p, n)B r-76. A pressed copper (I) selenide pellet containing enriched Se-76 i s used as a target. Irradiation of a 180 mg/cm(2) target with 16 --> 8 MeV protons gives a yield of 65-70 MBq/mu Ah EOB. In our target set-u p with a simple water cooling, the target can withstand 14 mu A. Bromi ne-76 is separated with an efficiency of 65-75%, within 60-75 min usin g dry distillation at 1090 degrees C. The loss of target material is l ess than 1% per separation cycle and the target can be re-used several times. Thermal chromatography is applied to separate Br-76 from trace s of volatilized selenium. The method allows a simple and economical p roduction of Br-76 With the use of accelerators commonly available at PET-centers. (C) 1998 Elsevier Science Ltd. All rights reserved.