title: Simplified fast and high yielding automated synthesis of [18F]fluoroethylcholine for prostate cancer imaging.
abstract: (11)C- and (18)F-labeled choline analogues are successful tracers for prostate cancer imaging using positron emission tomography (PET). Due to the practical advantages of the longer-living radioisotope (18)F (t(1/2)=110 min) instead of (11)C (t(1/2)=20 min), [(18)F]fluoroethylcholine has been introduced to increase the opportunity of widespread clinical application. Nevertheless, the various known synthetic methods provide [(18)F]fluoroethylcholine for human use only in moderate overall yields of up to 30% so far. Here, a new simplified and high yield two-step-synthesis for [(18)F]fluoroethylcholine is described for potential clinical applications starting from 2-bromoethyl triflate (BETfO) using a modified, commercially available fully automated synthesis module. All synthesis parameters were subsequently optimized resulting in a total yield of 47+/-5% (not decay corrected) in only 40min. [(18)F]fluoroethylcholine could be obtained ready for human use as physiological solution after fixation on Sep-Pak Accell Light cartridges (waters((R))) and formulation with saline without the need of GC or HPLC purification. Radiochemical purity was >99.9% and no contamination of the sterile solution with chemicals used during the synthesis was detected.
authors.affiliation: Klinik für Nuklearmedizin, Universitätsklinikum Schleswig-Holstein Campus Kiel, Arnold-Heller-Strasse 9, 24105 Kiel, Germany. mzuhayra@nuc-med.uni-kiel.de
authors.forename: M
authors.initials: M
authors.lastname: Zuhayra
authors.forename: A
authors.initials: A
authors.lastname: Alfteimi
authors.forename: L
authors.initials: L
authors.lastname: Papp
authors.forename: U
authors.initials: U
authors.lastname: Lützen
authors.forename: A
authors.initials: A
authors.lastname: Lützen
authors.forename: C
authors.initials: C
authors.lastname: Von Forstner
authors.forename: B
authors.initials: B
authors.lastname: Meller
authors.forename: E
authors.initials: E
authors.lastname: Henze
mesh_terms: D001331:Automation; D002794:Choline / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D006801:Humans; D008297:Male; D015394:Molecular Structure; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D011854:Radiochemistry; D013997:Time Factors
chemical_list: C448902:fluoroethylcholine; D002794:Choline