National Superconducting
Cyclotron Laboratory

Greg Severin
Greg Severin
Assistant Professor of Chemistry
PhD 2010, Nuclear Physics, University of Wisconsin-Madison
Joined NSCL in 2016
Phone 517-908-7124
Office 2014

Greg Severin

Beam interactions at NSCL produce a wide variety of radionuclides. Careful tuning through the fragment separator selects one of these exotic products for on-line experiments, while the remainders are captured in beam stops and target-system components. By implementing chemical post-processing of the collection-sites we will be able access the unused radionuclides for off-line experiments. The purpose of my research is to develop the chemical procedures to harvest and purify the off-line radionuclides in order to expand the palette of research-ready isotopes at NSCL, and eventually at FRIB.

One of the most important applications of novel and unconventional radionuclides is in medicine. Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), RadioImmunoTherapy (RIT), and Peptide Receptor RadioTherapy (PRRT) rely upon a broad selection of nuclear and chemical properties for optimizing clinical effectiveness. In addition, preclinical radiotracing, a critical screening tool for drug development, requires radionuclides that are chemically and physically matched to specific pharmacokinetic processes. Therefore, it is important for medicinal radiochemists to have access to a large selection of high purity and high specific activity radionuclides. NSCL and FRIB will constantly accumulate a unique inventory of medically relevant radionuclides that will be extremely valuable once isolated and purified.

The first goals of the radiochemistry program at NSCL and FRIB will be to isolate 47Ca and 76Kr as generator parents for 47Sc and 76Br respectively (figure, below). 47Sc is an important radionuclide for RIT, and 76Br is to be used for PET research. By setting up an ion exchange collection system for 47Ca, and a noble gas purification routine for trapping 76Kr, we will have the necessary infrastructure to begin harvesting other important gaseous or ionic radionuclides. Ideally, this will provide pure radionuclides for research projects in medicine, chemistry, botany, nuclear physics and other diverse fields and applications.

Selected Publications

ImmunoPET/MR imaging enables specific detection in vivo of Aspergillus fumigatus infection, Rolle, A-M, et al, Proc Natl Acad Sci 2016 vol. 113 no. 8, E1026–E1033

Measurement of the branching ratio for the beta decay of 14O, Voytas PA, et al, Phys Rev C 2015 vol. 92, 065502.

Novel Preparation Methods of 52Mn for ImmunoPET Imaging, Graves, SA et al, Bioconjug Chem, 2015 vol 26, no. 10, pp. 2118-2124.

Bringing radiotracing to titanium-based antineoplastics: solid phase radiosynthesis, PET and ex-vivo evaluation of antitumor agent [45Ti](salan)Ti(dipic) Severin GW et al, J Med Chem, 2015 vol. 58 no. 18, pp. 7591-7595.