A simple method of correcting 99Mo breakthrough from a 99mTc-99Mo generator.

Abstract

The eluent of a 99mTc-99Mo commercial generator is routinely checked for contamination by 99Mo. Infrequently we have found a concentration of 99Mo higher than the level permitted by AEC regulations (1 µCi 99Mo/mCi of 99mTc). A method of reducing the level of 99Mo contamination by passing the contaminated eluent through a second exhausted generator was suggested by E. R. Squibb & Sons, Inc. Though tandom elution is known to increase the yield of 99mTc (1), its use in the correction of 99Mo breakthrough has not previously been reported. Method The eluent contaminated with 99Mo was passed through a recently exhausted generator which had been demonstrated to be free of significant contamination by 99Mo while in use. Prior to and following the passage of the contaminated eluent through the exhausted generator, levels of 99Mo were measured by two different methods. In the first: method, described in the Squibb pamphlet,3 the total eluent in a lead shield approximately 1'4 inch thick was compared to a l37Cs stan...