Natural and artificial siderophores: Iron-based applications and beyond

Siderophores are iron chelators secreted by microorganisms to scavenge iron from the environment. Natural siderophores have gained remarkable importance because their conjugates can be applied as antibiotics and diagnostic imaging agents. By utilizing the iron uptake system of microorganisms, functional molecules such as antibiotics or imaging agents can be delivered into cells. Notably, artificial siderophores have also been developed to increase stability and broaden metal chelating diversity. Various strategies, including backbone fine-tuning, artificial chelation moieties, and direct metal swapping, can be employed. Therefore, artificial siderophores can bind biorelated metals or radioactive isotopes, expanding their biological and medical applications. The aim of this review is to introduce recent advances in natural and artificial siderophore applications and highlight future challenges in this area of research.