RADIOLABELING OF PHARMACEUTICAL DOSAGE FORMS BY NEUTRON-ACTIVATION OFSM-152

Samarium-152 can be activated in a neutron flux for the labelling of p harmaceutical dosage forms for evaluation by gamma scintigraphy. The s amarium is incorporated as samarium oxide powder which is available wi th Sm-152 in its natural isotopic abundance or isotopically enriched. The yield of Sm-153 was reduced considerably following the neutron act ivation of the non-isotopically enriched oxide. This can be attributed to the high neutron capture by Sm-149 present in the non-isotopically enriched oxide. In order to keep the mass of the added oxide powder t o the minimum and also to reduce the neutron irradiation time, it is r ecommended that samarium oxide enriched with Sm-152 should be used rou tinely when radiolabelling pharmaceutical dosage forms.