Synthesis of Short-Lived Radiotracers

<正> Positron emission tomography （PET） has become a powerful tool for non-invasive investi-gations of basic biological and physiological processes in vivo, for example: blood flow, transport andmetabolism of natural substrates and localization and characterization of receptor systems. The aim ofthe synthesis of short-lived radiotracers is to develop the PET probes. Cyclotron-produced 11C(t1/2:20min), 13N(t1/2:10min), 15O(t1/2:2min) and 18F(t1/2:110min) are gaining ever inereasing attentionand being actively utilized in clinical research and application, because they could be incorporated intonaturally oocurring biomolecules or drugs of various class without alteration of the compounds' definedfunctions in living systems. During recent years lots of 11C and 18F-labelled ligands has been synthe-sized for a number of receptor systems such as opiate, dopamine, serotonin, benzodiazepine, his-tamine, nicotine and muscarine. Ohmetentanyl, a new, highly potent and selective agonist for opiateμ-receptor found in this laboratory was labelled with carbon-11 in CEA, France.