Labeling of human C-peptide by conjugation with N-succinimidyl-4-[F-18]fluorobenzoate

We have labeled proinsulin connecting peptide (C-peptide) with fluorine-18 (t(1/2) = 109.7min) in order to perform in vivo biodistribution and pharmac okinetic studies with position emission tomography (PET). This study report s the optimization of the conjugation labeling in the N-terminal with N-suc cinimidyl-4-[F-18]fluorobenzoate ([F-18]SFB). In preparative runs N-4-[F-18 ]fluorobenzoyl-C-peptide ([F-18]FB-C-peptide) was produced in 8-12% decay-c orrected yields, counted from resolubilized [F-18]F-, in less than 5h. The specific radioactivity of [F-18]FB-C-peptide, determined using ELISA for on e of the preparations, was around 70 GBq/mu mol at end of synthesis. Copyri ght (C) 2001 John Wiley & Sons, Ltd.