Separation of radiolabelled arsenic compounds produced by neutron irradiation of organoarsenic compounds

Results are presented for the separation of radiolabelled arsenic compounds obtained by the irradiation of organoarsenic compounds in a nuclear reacto r. Previously developed chromatographic techniques with element-specific de tection were used and further improved to measure the As-76 activities and As concentrations of the arsenic-containing decomposition products formed. Since the recoil energy available during irradiation is high enough to brea k molecular bonds, a range of radiolabelled arsenic compounds were produced , depending on the conditions (type of compound, matrix and irradiation tim e). The most extensively investigated compound, viz, arsenobetaine, yielded , when irradiated as solid material for 60 min, 11 radiolabelled arsenic co mpounds, of which eight could be identified. Theoretically, an overall spec ific activity of 3.7 GBq g(-1) was expected, but experimentally specific ac tivities were found from 0.5 GBq g(-1) (for arsenobetaine) to more than 380 0 GBq g(-1) (for arsenate). (C) 1999 Elsevier Science B.V. All rights reser ved.