In:
Radiochimica Acta, Walter de Gruyter GmbH, Vol. 101, No. 5 ( 2013-05), p. 339-346
Abstract:
Rhenium-186g ( T 1/2 = 89.2 h) is a β − emitter suitable for therapeutic applications. Current production methods rely on reactor production via 185 Re( n , γ ) which results in low specific activities, thereby limiting its use. Production by p , d activation of enriched 186 W results in a 186g Re product with a higher specific activity, allowing it to be used for targeted therapy with limited receptors. A test target consisting of pressed, sintered nat WO 3 was proton irradiated at Los Alamos (LANL-IPF) to evaluate product yield and impurities, irradiation parameters and wet chemical Re recovery for proof-of-concept for bulk production of 186g Re. We demonstrated isolation of 186g Re in 97% yield from irradiated nat WO 3 targets within 12 h of end of bombardment (EOB) via an alkaline dissolution followed by anion exchange. The recovery process has potential for automation, and WO 3 can be easily recycled for recurrent irradiations. A 186g Re batch yield of 42.7 ± 2.2 μCi/μAh or 439 ± 23 MBq/C was obtained after 24 h in an 18.5 μA proton beam. The target entrance energy was determined to be 15.6 MeV. The specific activity of 186g Re at EOB was measured to be 1.9 kCi (70.3 TBq) mmol −1 , which agrees well with the result of a previous 185,186m Re co-production EMPIRE and TALYS modeling study assuming similar conditions. Utilizing enriched 186 WO 3 , we anticipate that a proton beam of 250 μA for 24 h will provide batch yields of 256 mCi (9.5 GBq) of 186g Re at EOB with specific activities even higher than 1.9 kCi (70.3 TBq) mmol −1 , suitable for therapy applications.
Type of Medium:
Online Resource
ISSN:
2193-3405
DOI:
10.1524/ract.2013.2031
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2013
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