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Updated: Jul 12, 2026
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Molecular Mechanics Investigation of Gadolinium(III) Complexes
David E. Reichert1, Robert D. Hancock, Michael J. Welch
1Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S. Kingshighway, St. Louis, Missouri 63110.
Abstract:
Parameters for the commercially available modeling package SYBYL have been developed for Gd(3+) complexes allowing these to be studied with molecular mechanics. With these parameters and a technique termed the "coordination scan", the coordination numbers of Gd(III) based complexes can be predicted, and thus the hydration number q determined. Knowledge of q has allowed the prediction of molar relaxivities based on correlations to literature values. In addition, the calculated value DeltaE(coord) was found to successfully predict the thermodynamic stability constants for polyamino carboxylate ligands with Gd(3+). Gadolinium complexes are commonly utilized as MRI contrast agents, and thus the techniques utilized in this work should aid in the development of new contrast agents.
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