Optimisation study of α-cyclotron production of At-211/Po-211g for high-LET metabolic radiotherapy purposes

The production of no-carrier-added (NCA) a-emitter At-211/Po-211g radionuclides for high-LET targeted radiotherapy and immunoradio therapy, through the Bi-209(alpha,2n) reaction, together with the required wet radiochemistry and radioanalytical quality controls carried out at LASA is described, through dedicated irradiation experiments at the MC-40 cyclotron of JRC-Ispra. The amount of both the gamma-emitter At-210 and its long half-lived alpha-emitting daughter Po-210 is optimised and minimised by appropriate choice of energy and energy loss of alpha particle beam. The measured excitation functions for production of the main radioisotopic impurity At-210 -> Po-210 are compared with theoretical predictions from model calculations performed at ENEA. (c) 2005 Elsevier Ltd. All rights reserved.