Investigating the Impact of Bound-Water Exclusion on the PARACEST MRI and Optical Properties of Lanthanide (III) Complexes

Lanthanide (III) complexes exhibit both paramagnetic and photophysical properties which make them attractive for Magnetic Resonance Imaging (MRI) and optical imaging applications. The combination of these two properties presents an opportunity to develop a single imaging agent that is applicable in two different modalities. The goal of the project is to develop Ln (III) complexes comprising a nonadentate ligand and a lanthanide ion, that can serve as bimodal agents. The main characteristic differentiating our proposed agents from traditional imaging agents is the exclusion of the water molecule typically associated with the lanthanide ion. Such a complex has the potential to facilitate the image-guided delineation of tumor boundaries during surgery. So far, three of the six synthetic steps have been successfully completed, and the identities of the products obtained have been verified by 1H-NMR and 13C-NMR Spectroscopy. Future work includes completion of the Ln(III) complex syntheses, and evaluation of the NMR and luminescence properties.