TY - JOUR
T1 - Comparative study of specific activity of [11C]methyl iodide
T2 - A search for the source of carrier carbon
AU - Iwata, Ren
AU - Ido, Tatsuo
AU - Ujiie, Akira
AU - Takahashi, Toshihiro
AU - Ishiwata, Kiichi
AU - Hatano, Kentaro
AU - Sugahara, Makoto
PY - 1988
Y1 - 1988
N2 - Any no-carrier-added 11C-compounds prepared from [11C]CH3I seem to coexist with at least about 0.2 μmol of its non-radioactive form (carrier). In order to elucidate the source of the carrier, 11C]CH3I prepared under various conditions was converted into several 11C-compounds and their specific activities were measured by high performance liquid chromatography. Carbon contamination of LiAlH4 was also examined by gas chromatography. It was shown that only a negligible amount of CO2 was brought with the irradiated target N2 gas and that the carrier amount decreased remarkably with the reduction of the amount and concentration of the LiAlH4THF solution but not to less than 0.2 μmol. The use of Et2O or Pr2O instead of THF was found to give EtOH or PrOH, respectively, together with MeOH, all in small amounts. Hence, the 0.2 μmol carrier can be regarded as being originated in MeOH formed from a trace of THF remaining in the LiALH4 after its drying step.
AB - Any no-carrier-added 11C-compounds prepared from [11C]CH3I seem to coexist with at least about 0.2 μmol of its non-radioactive form (carrier). In order to elucidate the source of the carrier, 11C]CH3I prepared under various conditions was converted into several 11C-compounds and their specific activities were measured by high performance liquid chromatography. Carbon contamination of LiAlH4 was also examined by gas chromatography. It was shown that only a negligible amount of CO2 was brought with the irradiated target N2 gas and that the carrier amount decreased remarkably with the reduction of the amount and concentration of the LiAlH4THF solution but not to less than 0.2 μmol. The use of Et2O or Pr2O instead of THF was found to give EtOH or PrOH, respectively, together with MeOH, all in small amounts. Hence, the 0.2 μmol carrier can be regarded as being originated in MeOH formed from a trace of THF remaining in the LiALH4 after its drying step.
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U2 - 10.1016/0883-2889(88)90084-6
DO - 10.1016/0883-2889(88)90084-6
M3 - Article
AN - SCOPUS:0023945361
VL - 39
SP - 1
EP - 7
JO - Applied Radiation and Isotopes
JF - Applied Radiation and Isotopes
SN - 0969-8043
IS - 1
ER -