Details

Autor(en) / Beteiligte

• Cagle, Dawson W
• Thrash, Thomas P
• Alford, Michael
• Chibante, L. P. Felipe
• Ehrhardt, Gary J
• Wilson, Lon J

Titel

Synthesis, Characterization, and Neutron Activation of Holmium Metallofullerenes

Ist Teil von

• Journal of the American Chemical Society, 1996-08, Vol.118 (34), p.8043-8047

Ort / Verlag

American Chemical Society

Erscheinungsjahr

1996

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Isolation of the first macroscopic quantities of endohedral holmium metallofullerenes (principally Ho@C82, Ho2@C82, and Ho3@C82 by LD-TOF mass spectrometry) has been accomplished by carbon-arc and preparative HPLC methodologies. The detailed procedure for production and isolation of the metallofullerenes includes a new technique whereby holmium-impregnated electrodes are prepared simply by soaking porous graphite rods in an ethanolic solution of Ho(NO3)3·xH2O. Monoisotopic 165Ho offers a unique combination of advantages for neutron-activation studies of metallofullerenes, and purified samples containing 165Ho@C82, 165Ho2@C82, and 165Ho3@C82 have been activated by high-flux neutron irradiation (Φ = 4 × 1013 n cm-2 s-1) to generate 166Ho metallofullerenes, which undergo β- decay to produce stable 166Er. Chemical workup of the irradiated samples, followed by re-irradiation, has been used to demonstrate that observed decomposition of holmium metallofullerenes is due mainly to “fast” neutron damage rather than to holmium atom nuclear recoil (E max = 200 eV). This implies that metallofullerene damage can be minimized by using neutron fluxes with the highest possible thermal component. A detailed analysis of the neutron-activation results is presented as a prelude to the possible use of neutron-activated metallofullerenes in nuclear medicine.