Preparation of high specific-volume solutions of technetium-99m and rhenium-188

Because of the high content of inactive molybdenum/tungsten in neutron-irradiated MoO3/WO3, large columns containing alumina are needed to produce chromatographic 99Mo→99mTc/188W→188Re generators. This results in large elution volumes containing low concentrations of 99mTc/188Re. The system described is based on generator elution with acetone. 99mTc-pertechnetate/188Re-perrhenate can conveniently be concentrated not, vert, similar10-fold by evaporation. This new approach also works very effectively to yield high specific-volume solutions of 99mTc-pertechnetate from a fission 99Mo-loaded alumina generator towards the end of its normal working life.