THE GEL GENERATOR - A VIABLE ALTERNATIVE SOURCE OF TC-99M FOR NUCLEAR-MEDICINE

The majority of the world's supply of Tc-99m is derived from generator s in which fission produced Mo-99 is adsorbed on to alumina. While suc h systems consistently produce Tc-99m with excellent physico-chemical and biomedical properties, their manufacturing processes, commencing w ith the irradiation of U-235, involve numerous complications with the result that few organisations, worldwide, are willing to participate i n such an endeavour, despite the size of the market (> SUS 100,000,000 per annum). Encouraging results from basic research on an alternative generator system, based upon zirconium molybdate gel prepared from ne utron irradiated molybdenum trioxide, was the stimulus for the decisio n to build a small pilot plant at Lucas Heights to manufacture the new generator under conditions akin to routine production. From this seri es of generators, a database of comprehensive performance characterist ics has been constructed to show that, indeed, (n,y) Mo-99 can be succ essfully exploited to provide an acceptable source of Tc-99m for use i n both nuclear medicine clinics and centralised radiopharmacies. (C) 1 997 Elsevier Science Ltd.