Endogenous compounds labeled with radionuclides of short half-life-some perspectives

In the article, the strategy and synthesis of some endogenous compounds labeled mainly with 11C are presented. There are some examples illustrating how endogenous labeled compounds in connection with positron emission tomography have unique properties to describe various biological processes, and a few examples of the use of tracers labeled with 13N and 15O are also discussed. Labeled endogenous compounds may be an important asset to describe the conditions and the status of biological systems and might therefore be a key for the future search of individualized medicine. Copyright © 2013 John Wiley & Sons, Ltd. Positron emission tomography has made it possible to follow the fate of an atom of key elements of life in molecules in living tissue and organs. Endogenous molecules labeled with positron emitting radioisotopes such as 11C, 13N, and 15O, instead of natural stable isotopes, open up a new window and opportunities to understand and track in vivo biological processes that are a consequence of the evolution.