title: Highly efficient automated synthesis of [(11)C]choline for multi dose utilization.
abstract: [(11)C]Choline has been under investigation as a PET ligand for imaging tumor tissue, especially prostate cancer. An improved, automated synthesis of the tracer now was established. [(11)C] Choline was produced by labeling 2-(dimethylamino)-ethanol (DMAE) with [(11)C]CH(3)I in a Tefzel tube at room temperature without solvent. The product was purified using a cation exchange cartridge. Reaction conditions were optimized with respect to synthesis time and amount of DMAE, resulting in radiochemical yields higher than 80% using 60 microl of DMAE in 20 min, radiochemical purity was >99% and residual DMAE was below 10 ppm. After (11)C-production of 1h at 50 microA [(11)C]choline activities of 30.0+/-5.6 GBq (n = 29) were obtained in sterile solution ready for intravenous administration.
authors.affiliation: PET-Zentrum, Radiopharmazie, Universitätsklinikum Tübingen Röntgenweg 15, Tübingen D-72076, Germany. gerald.reischl@uni-tuebingen.de
authors.forename: G
authors.initials: G
authors.lastname: Reischl
authors.forename: C
authors.initials: C
authors.lastname: Bieg
authors.forename: O
authors.initials: O
authors.lastname: Schmiedl
authors.forename: C
authors.initials: C
authors.lastname: Solbach
authors.forename: H-J
authors.initials: HJ
authors.lastname: Machulla
mesh_terms: D001331:Automation; D002247:Carbon Isotopes; D002794:Choline / Q000138:chemical synthesis*; D006801:Humans; D007202:Indicators and Reagents; D007553:Isotope Labeling / Q000379:methods*; D008297:Male; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging; D014055:Tomography, Emission-Computed
chemical_list: D002247:Carbon Isotopes; D007202:Indicators and Reagents; D002794:Choline