title: Synthesis of isomers of 18F-labelled amino acid radiopharmaceutical: position 2- and 3-L-18F-alpha-methyltyrosine using a separation and purification system.
abstract: To diagnose cancers with radiolabelled amino acid using positron emission tomography, we have constructed a separation and purification system for the production of L-18F-alpha-methyltyrosine (L-18FAmT). This system could provide radioprotection and consistent production of L-18FAmT. L-18FAmT was synthesized and purified and the efficiency of the system was examined. The radiochemical yield of L-18FAmT was 20.3 +/- 5.1% (n = 5) based on the radioactivity trapped in the reaction vessel. The radiochemical purity was greater than 99.4 +/- 0.3% (n = 5). The radiochemical stability in phosphate-buffered saline and human plasma was examined and little decomposition was observed by HPLC analysis. Our results indicate that the separation and purification system gave simple and quick synthesis of L-18FAmT with a large reduction in radiation exposure and consistent production of L-18FAmT.
authors.affiliation: Department of Nuclear Medicine, Gunma University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tomiyoshi
authors.forename: K
authors.initials: K
authors.lastname: Amed
authors.forename: S
authors.initials: S
authors.lastname: Muhammad
authors.forename: T
authors.initials: T
authors.lastname: Higuchi
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Endo
authors.forename: D
authors.initials: D
authors.lastname: Yang
mesh_terms: D000596:Amino Acids; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods; D005462:Fluorine Radioisotopes; D006801:Humans; D007202:Indicators and Reagents; D007536:Isomerism; D007553:Isotope Labeling / Q000379:methods; D008781:Methyltyrosines; D009369:Neoplasms / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000302:isolation & purification; D019805:alpha-Methyltyrosine
chemical_list: C105991:3-fluoro-alpha-methyltyrosine; D000596:Amino Acids; D005462:Fluorine Radioisotopes; D007202:Indicators and Reagents; D008781:Methyltyrosines; C105990:2-fluoro-alpha-methyltyrosine; D014443:Tyrosine; D019805:alpha-Methyltyrosine