PRODUCTION OF POSITRON-EMITTING IN-110M VIA THE CD-110(HE-3, 3N)SN-110-]IN-110M PROCESS

Positron-emitting In-110m was produced in a two-step process. Irradiat ion of highly enriched Cd-110 with He-3-particles over an energy range of 36-25 MeV led to the formation of Sn-110, which after its fast rad iochemical separation from the target material was used to prepare a S n-110-->In-110m generator. The radiochemical separation consisted of a thermochromatographic volatilization of (SnCl4)-Sn-110 from metallic Cd-110 targets in a small quartz apparatus at 800 +/- 10 degrees C wit hin 20 min, followed by its removal from the quartz tube via dissoluti on in hydrochloric acid. The Sn-110 separation yield was >98% and the fraction contained only <10(-4)% of the target material. The solution was then transferred to a small Kieselgel 40 column to prepare a Sn-11 0-->In-110 elution generator. The In-110 was eluted quantitatively wit hin 1 mi of 0.02 M hydrochloric acid. The only detectable isotopic imp urity was In-111, generated from the co-formed Sn-111-contamination. I ts percentage decreased from about 0.8% at Ih after the end of bombard ment to <0.01% at 7 h. The final solution was free of any traces of Cd . In the first experiments more than 15 mCi of In-110m was delivered p er generator. Copyright (C) 1997 Elsevier Science Ltd