High yield one-pot production of [18F]FCH via a modified TRACERlab FxFN module

Introduction: [F-18]Fluoromethylcholine ([F-18]FCH) is a potent tumors imaging agent. In order to fulfill the demand of pre-clinical and clinical studies, we have developed an automated high yield one-pot synthesis of this potent tumors imaging agent. Methods: [F-18]FCH was synthesized using a modified TRACERlab Fx(FN) module. Briefly, dibromomethane (10% in CH3CN) was fluorinated with K[F-18]/K (2.2.2) in a glassy carbon reaction vessel at 120 degrees C for about 5 min to generate [F-18]fluorobromomethane ([F-18]FBM). The resulting [F-18]FBM was then bubbling (He, 700 mL/min) through four Sep-Pak (R) Silica Plus Long cartridges to react with dimethylaminoethanol (10% DMAE in 0.3 mL DMSO) which was pre-loaded on Sep-Pak (R) C-18 Plus Short cartridge. The [F-18]FCH was purified by solid-phase extraction (SPE) using one Sep-Pak (R) C-18 Plus Short and one Sep-Pak (R) CM Plus Short in series. The quality of [F-18]FCH synthesized by this method was verified by HPLC and TLC as compared to authentic sample. Results: Using this improved one-pot method, the RCY of [F-18]FCH was 18.8 +/- 2.1% (EOB, n = 27) in a synthesis time of 49 +/- 5 min from EOB. The radiochemical purity of [F-18]FCH was greater than 90% and the residual DMAE concentration in the final product was less than 10 ppm. Conclusions: This optimized method could fulfill the demand of [F-18]FCH for both pre-clinical and clinical studies, especially for nearby study sites without a cyclotron.