An automated one-step one-pot [(18)F]FCWAY synthesis: development and minimization of chemical impurities.
Nucl Med Biol
; 34(4): 433-8, 2007 May.
Article
em En
| MEDLINE
| ID: mdl-17499733
ABSTRACT
[(18)F]FCWAY (N-{2-[4-(2-methoxyphenyl)piperazino]}-N-(2-pyridinyl)trans-4-fluorocyclohexanecarboxamide) has been prepared routinely as a serotonin 5-HT(1A) receptor ligand for clinical human studies. We have developed an automated one-step radiosynthesis using a modified Nuclear Interface C-11 Methylation System. The chemical synthesis of an appropriate methanesulfonate precursor for single-step nucleophilic substitution with [(18)F]fluoride ion and the adaptation of radiochemical synthesis to an automated production module were accomplished. Following purification of a substrate using countercurrent chromatography, radiochemical yield increased from 18.9+/-0.3% to 21.9+/-2.2%. In addition, reduction of chemical impurities from about 40% to about 20% of total mass was observed. Further improvements in chemical purity were achieved by minimization of side reactions by modification of reaction conditions and optimization of the high-performance liquid chromatography method for the purification of the final radiopharmaceutical. Optimized automated synthesis produced [(18)F]FCWAY in a radiochemical yield of 28+/-6% at a chemical purity of 99.3% based on the absorbance of FCWAY at 254 nm and with a specific activity of 3433+/-1015 mCi/micromol at the end of bombardment, all calculated from the same 50 runs.
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Base de dados:
MEDLINE
Assunto principal:
Piperazinas
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Compostos Radiofarmacêuticos
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Cicloexanos
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Receptor 5-HT1A de Serotonina
Idioma:
En
Ano de publicação:
2007
Tipo de documento:
Article