Abstract
Re-186g (T-1/2 = 3.7183 d, E-(beta)mean(-)= 346.7 keV, I-(beta)mean(-) = 92.59%), a mixed beta and gamma-emitter shows great potential for use in theranostic applications. The dominant Re-185(n,gamma) route, via use of a nuclear reactor, provides 1(86g)Re in carrier added form with low specific activity, while cyclotrons offer no carrier-added (NCA) high specific activity production of 186 gRe. However, to be able to select the best possible nuclear reaction and to optimize the production route via the use of a cyclotron, information on the excitation function for the reaction of interest as well as for the competing reactions is necessary. Accordingly, we have conducted a detailed study of the excitation functions for W-nat(d, x) reactions in seeking optimized parameters for the NCA production of 186 gRe. Noting a discrepancy among the experimental data, we made an evaluation of the available literature, finally selecting optimum parameters for the production of Re-186g via the W-186(d,2n) Re-186 reaction. These beam parameters were then used for batch production of Re-186g by irradiating an enriched W-186 metallic powder target, followed by a subsequent automated chemical separation process. The preliminary results show 98.1% radionuclidic purity of Re-186g at 8 h subsequent to the End of Bombardment (EOB), offering the potential for use in clinical applications.