A reverse 230U/226Th radionuclide generator for targeted alpha therapy applications

Nucl Med Biol. 2020 Nov-Dec:90-91:69-73. doi: 10.1016/j.nucmedbio.2020.09.006. Epub 2020 Sep 30.

Abstract

Purpose: Thorium-226 (half-life 30.6 m) is a radionuclide of interest for use in targeted alpha therapy applications. Due to its short half-life, 226Th must be provided through a radionuclide generator system from its parent 230U (20.8 d). Furthermore, as the half-life of 226Th is very short, it should be provided in a form that is directly amenable to use in biomedical applications.

Methods: A reverse radionuclide generator system was developed employing a DGA extraction chromatography column. A 230U/226Th parent/daughter solution in equilibrium is added to a DGA column in >6 M HCl. The parent 230U is eluted first in 0.1 M HNO3 followed by elution of 226Th in 0.1 M citrate buffer pH 5.

Results: Thorium-226 was recovered from the radionuclide generator column with >96% yield. Greater than 99.5% of the 230U parent was isolated for reuse in the generator. Long term evaluation over six weeks demonstrated consistent supply of 226Th with greater than 99.5% radionuclidic purity. The only contaminant found in the final product was 230U (<0.5%).

Conclusions: The reverse radionuclide generator described herein was shown to be a feasible method for providing 226Th in high yield, purity and in a chemical form that is amenable for direct use in biomedical applications.

Keywords: (226)Th; (230)U/(226)Th radionuclide generator; Targeted alpha therapy.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alpha Particles* / therapeutic use
  • Radiochemistry / instrumentation
  • Radiochemistry / methods
  • Radioisotopes / chemistry
  • Radionuclide Generators
  • Thorium* / chemistry

Substances

  • Thorium
  • Radioisotopes