Ligands Bearing Picolinate Groups as Potential Chelators for Application in Nuclear Medicine

Some metal radionuclides can be used in diagnostic methods for imaging, such as single-photon emission computed tomography (99mTc, 111In) and positron emission tomography (PET) (44Sc, 64Cu, 68Ga), as well as for therapeutic applications (47Sc, 90Y, 177Lu, 212Pb, 212/213Bi, 225Ac). A chelator, e.g., a ligand that binds a radiometal ion into a strong stable coordination complex, is an important component of a radiopharmaceutical (RP) based on radio metals. In the past decade, as part of the search for new highly effective chelating molecules, the number of studies related to the production of picolinate ligands and the characterization of their complexes with diagnostic and therapeutic radionuclides has sharply increased. Moreover, conjugates with biomolecules based on these chelators have already been synthesized and studied. In this review, data on the binding of cations of radionuclides by picolinate-containing ligands of various types, as well as their conjugates, are systematized and analyzed.