PT  - JOURNAL ARTICLE
AU  - Matson, Michael L.
AU  - Villa, Carlos H.
AU  - Ananta, Jeyarama S.
AU  - Law, Justin J.
AU  - Scheinberg, David A.
AU  - Wilson, Lon J.
TI  - Encapsulation of α-Particle–Emitting <sup>225</sup>Ac<sup>3+</sup> Ions Within Carbon Nanotubes
AID  - 10.2967/jnumed.115.158311
DP  - 2015 Jun 01
TA  - Journal of Nuclear Medicine
PG  - 897--900
VI  - 56
IP  - 6
4099  - http://jnm.snmjournals.org/content/56/6/897.short
4100  - http://jnm.snmjournals.org/content/56/6/897.full
SO  - J Nucl Med2015 Jun 01; 56
AB  - 225Ac3+ is a generator of α-particle–emitting radionuclides with 4 net α-particle decays that can be used therapeutically. Targeting 225Ac3+ by use of ligands conjugated to traditional bifunctional chelates limits the amount of 225Ac3+ that can be delivered. Ultrashort, single-walled carbon nanotubes (US-tubes), previously demonstrated as sequestering agents of trivalent lanthanide ions and small molecules, also successfully incorporate 225Ac3+. Methods: Aqueous loading of both 225Ac3+ ions and Gd3+ ions via bath sonication was used to construct 225Ac@gadonanotubes (225Ac@GNTs). The 225Ac@GNTs were subsequently challenged with heat, time, and human serum. Results: US-tubes internally loaded with both 225Ac3+ ions and Gd3+ ions show 2 distinct populations of 225Ac3+ ions: one rapidly lost in human serum and one that remains bound to the US-tubes despite additional challenge with heat, time, and serum. The presence of the latter population depended on cosequestration of Gd3+ and 225Ac3+ ions. Conclusion: US-tubes successfully sequester 225Ac3+ ions in the presence of Gd3+ ions and retain them after a human serum challenge, rendering 225Ac@GNTs candidates for radioimmunotherapy for delivery of 225Ac3+ ions at higher concentrations than is currently possible for traditional ligand carriers.