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Rhenium-186 g (t_1/2 = 3.72 d) is a β– emitting isotope suitable for theranostic applications. Current production methods rely on reactor production by way of the reaction ¹⁸⁵Re(n,γ)^186gRe, which results in low specific activities limiting its use for cancer therapy. Production via charged particle activation of enriched ¹⁸⁶W results in a ^186gRe product with a much specific activity, allowing it to be used more broadly for targeted radiotherapy applications. Furthermore, this targets the unmet clinical need for more efficient radiotherapeutics.

Protactinium-230 (t_1/2 = 17.4 d) is the parent isotope of ²³⁰U (t_1/2 = 20.8 d), a radionuclide of interest for targeted alpha therapy (TAT). Column chromatographic methods have been developed to separate no-carrier-added ²³⁰Pa from proton irradiated thorium targets and accompanying fission products. Results reported within this paper demonstrate the use of novel sulfur bearing chromatographic extraction resins for the selective separation of protactinium. The recovery yield of ²³⁰Pa was 93 ± 4% employing a R₃P=S type commercially available resin and 88 ± 4% employing a DGTA (diglycothioamide) containing custom synthesized extraction chromatographic resin. The radiochemical purity of the recoveredmore » ²³⁰Pa was measured via high purity germanium γ-ray spectroscopy to be >99.5% with the remaining radioactive contaminant being ⁹⁵Nb due to its similar chemistry to protactinium. Finally, measured equilibrium distribution coefficients for protactinium, thorium, uranium, niobium, radium, and actinium on both the R₃P=S type and the DGTA resin in hydrochloric acid media are reported, to the best of our knowledge, for the first time.« less

Alpha-emitters are radionuclides that decay through the emission of high linear energy transfer α-particles and possess favorable pharmacologic profiles for cancer treatment. When coupled with monoclonal antibodies, peptides, small molecules, or nanoparticles, the excellent cytotoxic capability of α-particle emissions has generated a strong interest in exploring targeted α-therapy in the pre-clinical setting and more recently in clinical trials in oncology. Multiple obstacles have been overcome by researchers and clinicians to accelerate the development of targeted α-therapies, especially with the recent improvement in isotope production and purification, but also with the development of innovative strategies for optimized targeting. Numerous studies havemore » demonstrated the in vitro and in vivo efficacy of the targeted α-therapy. Radium-223 (²²³Ra) dichloride (Xofigo®) is the first α-emitter to have received FDA approval for the treatment of prostate cancer with metastatic bone lesions. There is a significant increase in the number of clinical trials in oncology using several radionuclides such as Actinium-225 (²²⁵Ac), Bismuth-213 (²¹³Bi), Lead-212 (²¹²Pb), Astatine (²¹¹At) or Radium-223 (²²³Ra) assessing their safety and preliminary activity. Finally, this review will cover their therapeutic application as well as summarize the investigations that provide the foundation for further clinical development.« less

Column chromatographic methods have been developed to separate no-carrier-added ¹¹¹Ag from proton irradiated thorium targets and associated fission products as an ancillary process to an existing ²²⁵Ac separation design. In this paper, we report the separation of ¹¹¹Ag both prior and subsequent to ²²⁵Ac recovery using CL resin, a solvent impregnated resin (SIR) that carries an organic solution of alkyl phosphine sulfides (R₃P = S) and alkyl phosphine oxides (R₃P = O). The recovery yield of ¹¹¹Ag was 93 ± 9% with a radiochemical purity of 99.9% (prior) and 87 ± 9% with a radiochemical purity of 99.9% (subsequent to)more » ²²⁵Ac recovery. Both processes were successfully performed with insignificant impacts on ²²⁵Ac yields or quality. Measured equilibrium distribution coefficients for silver and ruthenium (a residual contaminant) on CL resin in hydrochloric and nitric acid media are reported, to the best of our knowledge, for the first time. Finally and additionally, measured cross sections for the production of ¹¹¹Ag and ^110mAg for the ²³²Th(p,f)^110m,111Ag reactions are reported within.« less