Synthesis and evaluation of fluorine-18 labelled compounds for imaging of bacterial infections with pet

Syntheses of no carrier added (n.c.a.) 6-fluoro-1,4-dihydro-1-cyclopropyl-4-oxo-7-[4-[18F]fluoro-phenacyl-1-piperacinyl]-chinolincarboxylic acid ([18F]COPCA) and n.c.a. 4-[18F]fluoro-benzoyl-ubiquicidin 29-41 ([18F]UBI 29-41) are described. [18F]COPCA was synthesised within 120 min with a radiochemical yield of 9–12%. [18F]UBI 29-41 was synthesised within 150 min with a radiochemical yield of 15–20%. Both compounds had a specific activity of more than 35 GBq/μ mol. The biological activity was verified by measuring its binding to Staphylococcus aureus bacteria. Specific binding was found for [18F]UBI 29-41 (12–17%), whereas no specific binding for [18F]COPCA was found.