Determination of the Terbium-152 half-life from mass-separated samples from CERN-ISOLDE and assessment of the radionuclide purity

S M Collins; U Köster; A P Robinson; P Ivanov; T E Cocolios; B Russell; A J Fenwick; C Bernerd; S Stegemann; K Johnston; A M Gerami; K Chrysalidis; H Mohamud; N Ramirez; A Bhaisare; J Mewburn-Crook; D M Cullen; B Pietras; S Pells; K Dockx; N Stucki; P H Regan

doi:10.1016/j.apradiso.2023.111044

Determination of the Terbium-152 half-life from mass-separated samples from CERN-ISOLDE and assessment of the radionuclide purity

Appl Radiat Isot. 2023 Dec:202:111044. doi: 10.1016/j.apradiso.2023.111044. Epub 2023 Sep 27.

Authors

S M Collins¹, U Köster², A P Robinson³, P Ivanov⁴, T E Cocolios⁵, B Russell⁴, A J Fenwick⁴, C Bernerd⁶, S Stegemann⁵, K Johnston⁷, A M Gerami⁷, K Chrysalidis⁷, H Mohamud⁴, N Ramirez⁴, A Bhaisare⁴, J Mewburn-Crook⁴, D M Cullen⁸, B Pietras⁸, S Pells⁸, K Dockx⁵, N Stucki⁹, P H Regan¹⁰

Affiliations

¹ National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK; School of Mathematics and Physics, University of Surrey, Guildford, GU2 7XH, UK. Electronic address: sean.collins@npl.co.uk.
² Institut Laue-Langevin, 38042, Grenoble, France.
³ National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK; Christie Medical Physics and Engineering (CMPE), The Christie NHS Foundation Trust, Manchester, M20 4BX, UK; The University of Manchester, Manchester, M13 9PL, UK.
⁴ National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK.
⁵ KU Leuven, Institute for Nuclear and Radiation Physics, Celestijnenlaan 200D, 3001, Leuven, Belgium.
⁶ KU Leuven, Institute for Nuclear and Radiation Physics, Celestijnenlaan 200D, 3001, Leuven, Belgium; CERN - European Organization for Nuclear Research, Esplanade des Particules 1, 1217, Meyrin, Switzerland.
⁷ CERN - European Organization for Nuclear Research, Esplanade des Particules 1, 1217, Meyrin, Switzerland.
⁸ The University of Manchester, Manchester, M13 9PL, UK.
⁹ HEPIA, HES-SO, University of Applied Sciences and Arts Western Switzerland, Rue de la Prairie 4, 1202, Geneva, Switzerland.
¹⁰ National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK; School of Mathematics and Physics, University of Surrey, Guildford, GU2 7XH, UK.

PMID: 37797447
DOI: 10.1016/j.apradiso.2023.111044

Abstract

Terbium-152 is one of four terbium radioisotopes that together form a potential theranostic toolbox for the personalised treatment of tumours. As ¹⁵² Tb decay by positron emission it can be utilised for diagnostics by positron emission tomography. For use in radiopharmaceuticals and for activity measurements by an activity calibrator a high radionuclide purity of the material and an accurate and precise knowledge of the half-life is required. Mass-separation and radiochemical purification provide a production route of high purity ¹⁵²Tb. In the current work, two mass-separated samples from the CERN-ISOLDE facility have been assayed at the National Physical Laboratory to investigate the radionuclide purity. These samples have been used to perform four measurements of the half-life by three independent techniques: high-purity germanium gamma-ray spectrometry, ionisation chamber measurements and liquid scintillation counting. From the four measurement campaigns a half-life of 17.8784(95) h has been determined. The reported half-life shows a significant difference to the currently evaluated half-life (ζ-score = 3.77), with a relative difference of 2.2 % and an order of magnitude improvement in the precision. This work also shows that under controlled conditions the combination of mass-separation and radiochemical separation can provide high-purity ¹⁵²Tb.