A facile and rapid automated synthesis of 3′-deoxy-3′-[18F]fluorothymidine

AimTo develop a simplified and fully automated synthesis procedure of 3′-deoxy-3′-[18F]fluorothymidine ([18F]FLT) using PET-MF-2V-IT-I synthesis module.MethodsSynthesis of [18F]FLT was performed using PET-MF-2V-IT-I synthesis module by one-pot two-step reaction procedure, including nucleophilic fluorination of 3-N-t-butoxycarbonyl-1-[5′-O-(4,4′-dimethoxy triphenylmethyl)-2′-deoxy-3′-O-(4-nitrobenzenesulfonyl)-β-d-threopentofuranosyl]thymine (15 mg) as the precursor molecule with [18F]fluoride, and subsequent hydrolysis of the protecting group with 1.0 M HCl at the same reaction vessel and purification with SEP PAK cartridges instead of the HPLC system.ResultsThe automated synthesis of [18F]FLT with SEP PAK purification gave corrected radiochemical yield of 23.2±2.6% (n=6, uncorrected yield: 16–22%) and radiochemical purity of >97% within the total synthesis time of 35 min.ConclusionThe fully one-pot automated synthesis procedure with SEP PAK purification can be applied to the fully automated synthesis of [18F]FLT using commercial [18F]FDG synthesis module.