Advances in macrocyclic chelators for positron emission tomography imaging

Abstract

Abstract In recent years, radiometals have been successfully applied to medicine because of their breadth of decay properties and increased production and availability. Bifunctional chelators play a key role in radiometal‐based radiopharmaceuticals, affecting the labeling, targeting, and pharmacokinetics of bioconjugations and ensuring the stable complexation of the metal in vivo. The capacity of macrocycles to form complexes with extremely high thermodynamics, kinetics, and stability compared to acyclic chelators continues to pique the curiosity of pharmacists and biochemists among all prospective chelators utilized for the radiometal chelation. As new imaging modalities and therapeutic targets develop, the discovery of novel ligand structures with suitable chemical and biological features encourages the modification of chelators with charge and chemical properties. Herein, we present a comprehensive review of developments of macrocyclic chelators for PET radiopharmaceuticals, including innovative chelating agents with new structures and known chelating agent modifications, and their physical‐chemical properties, as well as their biological characteristics and applications in vivo.

Keywords

• bifunctional chelator
• macrocyclic chelators
• PET
• radiometals
• radiopharmaceuticals