Primer on gadolinium chemistry.
Gadolinium is widely known by all practitioners of magnetic resonance imaging (MRI) but few appreciate the basic solution chemistry of this trivalent lanthanide ion. Given the recent linkage between gadolinium contrast agents and nephrogenic systemic fibrosis, some basic chemistry of this ion must be more widely understood. This short primer on gadolinium chemistry is intended to provide the reader the background principles necessary to understand the basics of chelation chemistry, water hydration numbers, and the differences between thermodynamic stability and kinetic stability or inertness. We illustrate the fundamental importance of kinetic dissociation rates in determining gadolinium toxicity in vivo by presenting new data for a novel europium DOTA-tetraamide complex that is relatively unstable thermodynamically yet extraordinarily inert kinetically and also quite nontoxic. This, plus other literature evidence, forms the basis of the fundamental axiom that it is the kinetic stability of a gadolinium complex, not its thermodynamic stability, that determines its in vivo toxicity. J. Magn. Reson. Imaging 2009;30:1240-1248. (c) 2009 Wiley-Liss, Inc.
Sherry
A Dean
AD
Department of Chemistry, University of Texas at Dallas, Richardson, Texas, USA. dean.sherry@utsouthwestern.edu
Caravan
Peter
P
Lenkinski
Robert E
RE
D000818:Animals; D003287:Contrast Media / Q000009:adverse effects* / Q000737:chemistry* / Q000493:pharmacokinetics; D005682:Gadolinium / Q000009:adverse effects* / Q000737:chemistry* / Q000493:pharmacokinetics; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000009:adverse effects*; D051379:Mice; D008956:Models, Chemical; D054989:Nephrogenic Fibrosing Dermopathy / Q000139:chemically induced* / Q000378:metabolism; D051381:Rats
D003287:Contrast Media; D005682:Gadolinium