Coordination Compounds in Diagnostic Imaging and Theranostics: Emerging Trends in Biomedical Applications

Abstract:

The rapid evolution of biomedical sciences has significantly transformed disease diagnosis and treatment through the integration of advanced imaging technologies and targeted therapeutics. Coordination compounds have emerged as indispensable components of modern diagnostic imaging and theranostics because of their unique physicochemical properties, versatile coordination chemistry, tunable electronic structures, and excellent biocompatibility. Metal-based coordination complexes containing gadolinium, technetium, gallium, copper, indium, zirconium, manganese, ruthenium, iridium, and platinum have demonstrated remarkable applications in magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), fluorescence imaging, photoacoustic imaging, and multimodal imaging platforms. Recent advances in ligand engineering, nanotechnology, molecular targeting, and bioinorganic chemistry have enabled the development of multifunctional coordination compounds capable of simultaneously diagnosing and treating diseases, particularly cancer. These theranostic agents integrate imaging, drug delivery, photodynamic therapy, photothermal therapy, radiotherapy, and targeted chemotherapy within a single molecular platform, thereby improving treatment precision and patient outcomes. This review discusses the chemistry of coordination compounds used in diagnostic imaging, recent advances in theranostic systems, biomedical applications, current challenges, and future perspectives for precision medicine.