Peptide radiopharmaceuticals for diagnosis and therapy

Radiolabelled peptides are an emerging class of radiopharmaceuticals that s hare chemical and biological properties. From the chemical point of view th ey have a poly-amino acid structure varying from 3 to more that 200 amino a cids, and they are labelled with different isotopes directly or by a linker . Biologically, they bind to specific cell membrane receptors, thus providi ng in vivo histopathological information for diagnostic put-poses, therapy follow-up or targeted radiotherapy. This paper reviews most of the radiolab elled peptides that have been tested in animals and humans in the fields of oncology, neurology, cardiology, inflammation/infection, atherosclerosis a nd thrombosis. A new classification is also proposed for peptides targeting tumour cells based on the biological function of target receptors. These t ailored radiopharmaceuticals are the basis of the new era of "molecular nuc lear medicine".