Actinium chelation and crystallization in a macromolecular scaffold

Journal Article · 15 July 2024 · Nature Communications

DOI: https://doi.org/10.1038/s41467-024-50017-5 · OSTI ID:2403106

Wacker, Jennifer N. ; Woods, Joshua J. ; Rupert, Peter B. ; Peterson, Appie ; Allaire, Marc ; Lukens, Wayne W. ; Gaiser, Alyssa N. ; Minasian, Stefan G. ; Strong, Roland K. ; Abergel, Rebecca J.

Abstract Targeted alpha therapy (TAT) pairs the specificity of antigen targeting with the lethality of alpha particles to eradicate cancerous cells. Actinium-225 [ ²²⁵ Ac; t _1/2  = 9.920(3) days] is an alpha-emitting radioisotope driving the next generation of TAT radiopharmaceuticals. Despite promising clinical results, a fundamental understanding of Ac coordination chemistry lags behind the rest of the Periodic Table due to its limited availability, lack of stable isotopes, and inadequate systems poised to probe the chemical behavior of this radionuclide. In this work, we demonstrate a platform that combines an 8-coordinate synthetic ligand and a mammalian protein to characterize the solution and solid-state behavior of the longest-lived Ac isotope, ²²⁷ Ac [t _1/2  = 21.772(3) years]. We expect these results to direct renewed efforts for ²²⁵ Ac-TAT development, aid in understanding Ac coordination behavior relative to other +3 lanthanides and actinides, and more broadly inform this element’s position on the Periodic Table.

• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 2403106
• Journal Information: Nature Communications, Journal Name: Nature Communications Journal Issue: 1 Vol. 15; ISSN 2041-1723
• Publisher: Nature Publishing GroupCopyright Statement
• Country of Publication: United Kingdom
• Language: English