Peptides and peptide hormones for molecular imaging and disease diagnosis

Numerous peptide-based molecular imaging probes with respect to their design strategies and applications are studied. Somatostatin (SST), integrin, gastrin-releasing peptide (GRP), cholecystokinin (CCK), R-melanocyte stimulating hormone (R-MSH), and glucagon-like peptide-1 (GLP-1) receptors have been identified and characterized for tumor receptor imaging. An imaging probe can be created through combination of a targeting peptide, a linker, and an imaging moiety. The new peptide associated probe should have high in ViVo uptake and retention in the target, with low background uptake in non-target tissues. Despite the rapid progress of a number of imaging modalities, nuclear imaging remains the premier clinical method. Both PET and SPECT have been well-developed and are widely used in daily practice. A critical step in the development of peptide probes for nuclear imaging is the radiolabeling process. Real-time imaging of biological processes in live cells and in vivo is one of the basic goals of modern optical imaging techniques.