@article{oai:repo.qst.go.jp:00047695,
 author = {Fukumura, Toshimitsu and Yamaguchi, Masatoshi and Suzuki, Kazutoshi and 福村 利光 and 山口 政俊 and 鈴木 和年},
 issue = {2},
 journal = {Radiochimica Acta},
 month = {Mar},
 note = {Radiolysis of [11C]iomazenil was investigated
in an aqueous solution. Preparation of [11C]iomazenil with
[11C]CH3I produced a good radiochemical yield, however,
its radiochemical purity was always less than 90% without
additives. This poor radiochemical purity was attributed to radiolysis
of [11C]iomazenil. The degradation of [11C]iomazenil
via radiolysis was markedly facilitated in the presence of
HCOONa (strong selective hydroxyl radical and hydrogen
atom scavenger). On the other hand, the radiolysis was
suppressed effectively in the presence of NaNO3 (selective
hydrated electron scavenger), suggesting participation of hydrated
electrons in the radiolysis of [11C]iomazenil. LC/MS
analysis of the degradation product suggested that the major
degradation product by radiolysis had a molecular weight of
285 corresponding to the deiodinated compound. The present
study showed that a decrease in the radiochemical purity
of [11C]iomazenil was attributed to the radiolysis via the
deiodination reaction by hydrated electron.},
 pages = {119--123},
 title = {Radiolysis of an aqueous [11C]iomazenil solution},
 volume = {92},
 year = {2004}
}