The GE FASTLab™ was programmed to perform the following protocol using a custom cassette layout (Supplementary Fig. ). The procedure was adapted from that previously reported by our group. (3 × 0.40 mL). The precursor 4 (10.0 mg, 28.8 µmol) was added to the reaction vessel as a solution in anhydrous DMSO (1 mL). Following heating at 150 °C for 25 min, the reaction temperature was lowered to 100 °C. Aqueous HCl (1 mL, 1 M) was added and the reaction mixture kept at 100 °C for 5 min. The reaction temperature was lowered to 70 °C, and a solution of ammonium acetate (3 mL, 20 mM) was added. After 5 min the reaction mixture was transferred into an external vial containing a solution of ammonium acetate (30 mL, 20 mM). Nitrogen was passed through the mixture for 20 s to encourage mixing. The crude product was extracted on to two C18 SepPak cartridges, using syringe 2 for loading in a stepwise manner. A slower loading was achieved by breaking down the syringe plunger movements into multiple programmed stop/start commands (12 × 5 second intervals) as reported previously . Washing with water (28 mL) was then performed in the same fashion. Both the extraction of [ 18 F]1 and washing steps were performed by loading onto the female end of the cartridge. Syringe 3 was then used to pass the MeOH eluent (20 mL) through the two C18 SepPak cartridges in a 'reverse elution', passing in the opposite direction to which the C18 SepPak cartridges were loaded and washed. The product was eluted through an external switch valve for collection in a glass vial to give [ 18 F]1 in 44 ± 7% RCY (n = 5) with >98% radiochemical purity as determined by radio-HPLC (Eclipse XDB-C18 , 9. MA (expressed in GBq/µmol) was measured using HPLC and was calculated using the equation: