Chapter 2: Biomedical Imaging: Advances in Radiotracer and Radiopharmaceutical Chemistry

The development of radiotracers and radiopharmaceuticals as biomedical imaging tools involves the integration of several types of expertise. First, one requires sufficient knowledge of the biological systems that are to be interrogated, in order to appreciate whether those systems would be appropriate for the biomedical problem. Second, one must be able to identify an appropriate compound-peptide, small molecule ligand or enzyme inhibitor that can selectively interact with that biological target. Finally, one must be able to design and synthesize the radiotracer–radiopharmaceutical using clinically relevant radionuclides. This latter factor requires an appreciation of the radiochemistry of the nuclides, including emission characteristics, physical half-lives, the methods for incorporation into carrier molecules and separation–purification. This chapter will briefly review the types of expertise needed to develop optimized radio-imaging agents and then provide three examples of how this has been achieved.