title: Reactivity of electrochemically concentrated anhydrous [18F]fluoride for microfluidic radiosynthesis of 18F-labeled compounds.
abstract: In order to demonstrate the usefulness of electrochemically concentrated [(18)F]fluoride the reactivity of the [K(+)/K.222] (18)F(-) complex concentrated in an aprotic solvent (ca. 60μL) was evaluated via nucleophilic (18)F-substitution reactions through radiosynthesis of [(18)F]FDG, [(18)F]FMISO, [(18)F]flumazenil and [(18)F]fluoromethyl bromide. The substitutions were carried out in a microfluidic reaction flow cell and the effects of reaction time, temperature, precursor concentration and reaction solvent on the (18)F-substitution yields were investigated. The (18)F-fluorination yields for the four (18)F-labeled compounds under optimized conditions (98% for protected [(18)F]FDG, 80% for protected [(18)F]FMISO, 20% for [(18)F]flumazenil and 60% for [(18)F]fluoromethyl bromide) were comparable to or higher than those obtained by conventional means. In this study it is clearly demonstrated that electrochemically concentrated [(18)F]fluoride enables microfluidic radiosynthesis by effectively reducing synthesis times and especially by increasing radiochemical yields of products labile at high temperatures.
authors: Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Japan.
authors: Rebecca
authors: R
authors: Wong
authors: Ren
authors: R
authors: Iwata
authors: Hidekazu
authors: H
authors: Saiki
authors: Shozo
authors: S
authors: Furumoto
authors: Yoichi
authors: Y
authors: Ishikawa
authors: Eiichi
authors: E
authors: Ozeki
mesh_terms: D004563:Electrochemistry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D007553:Isotope Labeling / Q000295:instrumentation*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D014867:Water / Q000737:chemistry
chemical_list: D005462:Fluorine Radioisotopes; D014867:Water