Remote control production of an aqueous solution of no-carrier-added 34mCl− via the 32S(α,pn) nuclear reaction

A remote system was established for the production of a biologically important radionuclide, chlorine-34m (32.0 min, β+ 53%, IT 47%). The 32S(α,pn)34mCl reaction on elemental sulfur of natural isotopic composition was adopted for the production method. The target sulfur was melted by heating in the target chamber and then irradiated with 65 MeV alpha particles (58.2 MeV on target) at 3 μA for 30 min. Generated 34mCl was extracted remotely with hot water from the molten sulfur in the target chamber. Within 20 min, [34mCl]chloride was obtained as a 10±3 mL aqueous solution at a yield of 450±90 MBq, which corresponds to a recovery efficiency of 79±17% (n=5). Both radionuclidic and radiochemical purities were more than 99% with a specific activity of 1.1 GBq/μmol. Non-radioactive impurities in the solution were identified as F−, Cl−, NO3−, SO42−; other unknown ions were also present.