How to determine free Gd and free ligand in solution of Gd chelates. A technical note
Article first published online: 28 SEP 2006
Copyright © 2006 John Wiley & Sons Ltd.
Contrast Media & Molecular Imaging
Volume 1, Issue 5, pages 184–188, September/October 2006
How to Cite
Barge, A., Cravotto, G., Gianolio, E. and Fedeli, F. (2006), How to determine free Gd and free ligand in solution of Gd chelates. A technical note. Contrast Media Mol Imaging, 1: 184–188. doi: 10.1002/cmmi.110
- Issue published online: 7 OCT 2006
- Article first published online: 28 SEP 2006
- Manuscript Accepted: 16 AUG 2006
- Manuscript Revised: 14 AUG 2006
- Manuscript Received: 11 AUG 2006
- Gd(III) quantification;
- contrast agents;
- Xylenol Orange
Gd(III) chelates are often used as reporting probes in magnetic resonance imaging applications. Their use relies on the assumption that their high stability ensures against the release of free ligand and free Gd3+ ions, which are both highly toxic to living systems. The presence of free Gd3+ ions may have a profound effect on the contrast in the MR image as they may form highly hydrated, macromolecular complexes endowed with very high relaxivity thus providing erroneous information on the extent of the contrast effect induced by the given reporting probe. Although the stability of a given complex may be high enough, the complexation step could not have been completed. Therefore any Gd complex preparation has to be carefully checked for the content of free ligand and free metal ions. Herein the currently used procedures that allow an assessment of the amounts of free metal ions and free ligand in a solution of a given Gd complex are described in detail. Copyright © 2006 John Wiley & Sons Ltd.