Screening of ligands for redox-active europium using magnetic resonance imaging.

We report a screening procedure to predict ligand coordination to Eu and Eu using magnetic resonance imaging in which bright images indicate complexation and dark images indicate no complexation. Here, paramagnetic Gd is used as a surrogate for Eu in the screening procedure to enable detection with magnetic resonance imaging. The screening procedure was tested using a set of eight ligands with known coordination to Eu and Eu, and results were found to be consistent with expected binding. Validation of the screening procedure with known coordination chemistry enables use with new ligands in the future.