Fluorescent cyclic peptides for cell imaging

Fluorescent cyclic peptides are excellent chemical scaffolds to build optical agents for molecular imaging. In addition to their favourable physicochemical properties, they can be modified with multiple organic fluorophores and generate useful probes for biological assays targeting specific proteins, namely receptors or enzymes. In this article, we review recent advances in the synthetic approaches for the preparation of fluorescent cyclic peptides as well as some of their applications in biological imaging, from in vitro live-cell imaging studies to in vivo characterisation of preclinical models.