High Specific Activity Sm-153 by Post Irradiation Isotope Separation

Samarium-153 (153Sm) has ideal nuclear properties for a variety of therapeutic applications; however, it is only available in low specific activity (radioactivity/weight) form. While large quantities can be made by the 152Sm(n,)153Sm reaction in a medium flux reactor such as at the University of Missouri Research Reactor Center (MURR), typical irradiation parameters result in less than 2% of the 152Sm target material being converted into 153Sm. Since chemical methods cannot be used to perform isotopic separation, this means that & gt;98% of the resultant pharmaceutical molecules are labeled with cold atoms and are therefore incapable of delivering the desired radiation-induced therapeutic effect. Electromagnetic isotope separation is routinely used in the production of enriched stable isotopes and in mass spectrometry; however, the successful development of an economically viable facility for processing relatively short-lived radioactive medical isotopes presents new challenges. Results of the Phase I project clearly indicate the technical feasibility of using this approach for processing 153Sm. Experimental ion source testing demonstrated high extracted Sm+ ion current, in excess of 1 mA. All key process steps were tested individually, including pre- and post- separation chemistry.