Fully automated radiosynthesis of [18F]fluoro-C-glyco-c(RGDfC): exploiting all the abilities of the AllInOne synthesizer

Abstract

Radiolabelled peptides are crucial tools for biomedical research purposes. Peptides are usually labeled with fluorine-18 via an indirect prosthetic group approach, which requires a complex multistep procedure not easily automatable. However, automation is a compulsory step of paramount importance to produce radiotracers with high reliability and minimal human involvement. Herein, we describe the fully automated radiosynthesis of [¹⁸F]fluoro-C-glyco-c(RDGfC) on an AllInOne (AIO) synthesizer, exploiting for the first time all the abilities of the AIO module. The radiotracer was prepared in high radiochemical purity via a challenging three-step sequence in 140 minutes with a decay-corrected radiochemical yield of 3.6 ± 0.4%. Presenting a high stability and an improved hydrophilicity, [¹⁸F]fluoro-C-glyco-c(RDGfC) could become a valuable tool in PET imaging for cancer diagnosis. Furthermore, the described automated procedure is modular and could be adapted to other prosthetic groups and/or peptides with minimal changes to afford a large panel of ¹⁸F-radiolabeled peptides.