Separation Science in Support of the Domestic Production of Medical Isotope Mo-99

McDonnell Douglas Engineering Auditorium

ChEMS Seminar

Dr. Iain May

Technical Staff Member, Los Alamos National Laboratory


Tc-99m (6hr half-life) is a radioisotope with a gamma emission ideally suited to a range of nuclear medicine applications. It is currently used in more than 30 million procedures per annum world-wide and two thirds of all nuclear medicine procedures in the US. Tc-99m is the beta decay product of the parent isotope Mo-99 (2.7 day half-life). This parent isotope is used to prepare Tc-99m generators supplied to hospitals, but the <3 day half-life can quickly lead to supply issues when there are breaks in production.

Currently the US relies on overseas suppliers of Mo-99 produced from U-235 fission, and where there is an overreliance on aging reactors which have historically operated with Highly Enriched Uranium (a proliferation risk). As part of the National Nuclear Security Administration NA-212 Office of European and African Threat Reduction Program, Los Alamos National Laboratory has been tasked to assist commercial entities with the development of a Mo-99 domestic production capability using Low Enriched Uranium in aqueous solution ‘fuels’. In collaboration with Argonne National Laboratory, we have been investigating the chemical separation of Mo-99 generated from the fission of U-235 in aqueous uranium solutions. We report the preparation and analysis of uranyl nitrate and uranyl sulfate solution ‘fuels,’ gamma spectroscopy results on irradiated samples, analysis of gaseous products and separation results using inorganic sorbents.


Dr Iain May is a Technical Staff Member within Chemistry Division at Los Alamos National Laboratory. Prior to coming to the US he worked both as an academic at the Center for Radiochemistry Research, University of Manchester, and in industry with British Nuclear Fuels. He has over 15 years' experience working with radioactive elements, particularly the actinides, for a range of applied and fundamental research chemistry projects. These projects have been related to nuclear waste management, nuclear fuel reprocessing and medical radioisotope production. Dr May Received a BSc in Chemistry from The University of Glasgow in 1992 (ICI Prize for Inorganic Chemistry) and a PhD in Inorganic Chemistry from The University of Durham (1996).