Production and Chemical Separation of No Carrier Added (nca) Lutetium-177

Abstract

Lutetium-177 dotatate gained FDA approval for use in certain neuroendocrine tumors, opening the door for research looking at other avenues of radiopharmaceutical use. With a half-life of 6.647 days and average ∖beta - particle range in soft tissue of ∼670 μm, 177Lu has promise for other therapy applications. Another benefit of 177Lu is that it produces low energy gammas (113 keV, 208 keV), suitable for imaging purposes, allowing biodistribution and excretion kinetics to be monitored. Lutetium-177 can be produced as carrier added (ca) and no carrier added (nca) from enriched 177Lu or 176Y b, respectively by two production routes: 176Lu(n,α)177Lu, 176Y b(n,α)177Y b→β-177Lu. The later requires separation of Lu from the Yb target following irradiation. The ORNL High Flux Isotope Reactor (HFIR) with a max thermal neutron flux of 2.1x1015 n⋅cm-2 ⋅s-1 (85 MW) is ideally suited to produce high specific activity 177Lu. Separating nca 177Lu is a complex process because it requires separating micro amounts of 177Lu from macro amounts of 176Y b and they are both part of the lanthanide series. The best method of separation will be tested from previous work to come up with a method that will cut down on waste, time, and improve the overall radio-purity of 177Lu.