Evaluation of 186WS2 target material for production of high specific activity 186Re via proton irradiation: separation, radiolabeling and recovery/recycling.

Enriched tungsten disulfide (¹⁸⁶WS₂) was evaluated at increasing proton beam currents (20–50 μA) and times (up to 4 h) on a GE PETtrace cyclotron for production of high specific activity (HSA) ¹⁸⁶Re. The HSA ¹⁸⁶Re was separated from the irradiated target as [¹⁸⁶Re][ReO₄]^– by a liquid–liquid extraction method and radiolabeled with a new N₂S₂ ligand (222-MAMA-N-ethylpropionate). The enriched ¹⁸⁶W was recovered from the extraction process, analyzed for purity and enrichment, and converted back to the disulfide (¹⁸⁶WS₂). The results demonstrate that the ¹⁸⁶WS₂ is an easily pressed target material that can withstand relatively high currents and can be readily recovered and recycled. The ¹⁸⁶Re produced was isolated in high specific activity and readily formed the radiotracers [¹⁸⁶Re][ReO(222-MAMA-N-ethylpropionate)] and [¹⁸⁶Re][Re(CO)₃(OH₂)₃] ⁺. [ABSTRACT FROM AUTHOR]