Fully Automated Preparation and Conjugation of N-Succinimidyl 4-[18F]Fluorobenzoate ([18F]SFB) with RGD Peptide Using a GE FASTlab™ Synthesizer

Purpose: The aim of this work was to automate the radiosynthesis of [F-18]SFB, a widely used reagent for the labeling of biomolecules with F-18 on a new generation commercial synthesis module (FASTLab (TM), GE Healthcare). Procedures: Two synthesis approaches were implemented on this module: the classical two-pot radiosynthesis and the more recently described one-pot method. Results: The two-pot approach affords [F-18]SFB with a 42% decay-corrected yield in 57 min (n = 24) with a chemical purity sufficient to avoid an intermediate HPLC purification. The recently established one-pot method, afforded a product with a lower chemical purity, in the conditions used in this report. The lower d.c. yield obtained (32% (n = 15)) was related to the low F-18 labeling yields obtained in MeCN compared with DMSO. The subsequent conjugation step with a RGD (PRGD2) peptide was also successfully automated. Conclusions: The formulated [F-18]FPRGD2 was obtained without any operator manipulation with a d.c. yield of 13% +/- 3% (n = 13) in 130 min, a radiochemical purity > 98% and a specific activity of 140 +/- 40 TBq/mmol.