title: Evaluation of an internal cyclotron target for the production of 211At via the 209Bi (alpha,2n)211 at reaction.
abstract: Astatine-211 is a 7.2 h half-life alpha-emitting radionuclide which has shown great promise for targeted radiotherapy. It is generally produced by cyclotron bombardment of bismuth metal targets with 28 MeV alpha-particles via the 209Bi(alpha,2n)211 At reaction. In order to provide 211At activity levels anticipated for clinical investigations, an internal target system has been designed and evaluated. The system has a grazing-angle configuration and leading- and trailing-edge monitors. Both aluminum and copper target backings were evaluated. With approx. 28 MeV alpha-particles, the 211At production efficiency was 41 +/- 7 MBq/microA.h, compared with 10.6 +/- 1.2 MBq/microA.h for an external target. Radionuclidic purity of 211At was high with no evidence of 210At.
authors.affiliation: Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: R H
authors.initials: RH
authors.lastname: Larsen
authors.forename: B W
authors.initials: BW
authors.lastname: Wieland
authors.forename: M R
authors.initials: MR
authors.lastname: Zalutsky
mesh_terms: D001246:Astatine / Q000737:chemistry* / Q000302:isolation & purification; D001729:Bismuth / Q000737:chemistry* / Q000302:isolation & purification; D017357:Cyclotrons; D005069:Evaluation Studies as Topic; D006207:Half-Life; D011854:Radiochemistry / Q000379:methods; D011868:Radioisotopes / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D011868:Radioisotopes; D001729:Bismuth; D001246:Astatine