@article{oai:repo.qst.go.jp:00044324,
 author = {Noguchi, Junko and Suzuki, Kazutoshi and 鈴木 和年},
 journal = {Nuclear Medicine and Biology},
 month = {Apr},
 note = {We have designed and constructed an automated device for the production of ultra-high specific activity 11C-labeled compounds via [11C]CH3I synthesized by the single pass I2 method. The optimum condition for the production of[11C]CH3I was determined to be 630degree C for oven-1 (reaction column), 50degree C for oven-2 (iodine column) and 50 ml/min for the He gas flow rate, and gave the maximum conversion ratio of [11C]CH3I,44%. [11C]Ro15-4513, known as an inverse agonist of the benzodiazepine receptor, was produced under optimized conditions. An i.v.injectable[11C]Ro15-4513 solution of 1500+/-490 MBq (n=6) with specific activity 4700+/-2500 GBq/mumol and a radiochemical purity of 98.2+/-2% was obtained automatically within 25 minutes (from EOB) by irradiating nitrogen gas containing 5% H2 with 18 MeV protons (14,2 MeV on target) at 20 muA for 20 minutes. The highest specific activity of 9700 GBq/mumol (at EOS) could be achieved,although the radiochemical purity was 92.4%. By the use of the ultra-high specific activity [11C]Ro15-4513,the super high affinity binding sites in the rat brain hippocampus could be clearly visualized even at the extremely low concentration of 0.66 pM Ro15-4513 by in vitro autoradiography.},
 pages = {335--343},
 title = {Automated synthesis of the ultra high specific activity of [11C]Ro15-4513 and its application in an extremely low concentration region to an ARG study},
 volume = {30},
 year = {2003}
}