Production of radioactive fullerene families using accelerators

Radioactive fullerenes, labeled with 11C, were produced and identified by HPLC with UV and BGO detectors. The compounds were produced by the 11C(γ,n)11C reaction, using a bremsstrahlung of Emax = 30 MeV. Soluble products, such as fullerene dimers produced by the reaction between two fullerene molecules, were also detected. The 11C nuclide was contained in a fullerene at the rate of about 60%–70% of the total amount of 11C produced when a C60 sample was irradiated. To confirm the production process, a mixture of C60 and boron was irradiated by a 12 MeV proton beam to implant from the outside of the fullerene cage, following the 11B(p,n)11C reaction. These results were very similar those involving a photonuclear reaction. This indicates that the 11C labeling process is due mainly to the recombination reaction between the 12C network and 11C.