Optimized relaxivity and stability of [Gd(H(2,2)-1,2-HOPO)(H 2O)]- for use as an MRI contrast agent

Christoph J. Jocher, Mauro Botta, Stefano Avedano, Evan G. Moore, Jide Xu, Silvio Aime, Kenneth N. Raymond

Research output: Contribution to journalArticlepeer-review

Abstract

Relaxometry and solution thermodynamic measurements show that Gd(H(2,2)-1,2-HOPO) is a good candidate as a contrast agent for magnetic resonance imaging (MRI-CA). Acidic, octadentate H(2,2)-1,2-HOPO forms a very stable Gd(III) complex [pGd = 21.2(2)]. The coordination sphere at the Gd(III) center is completed by one water molecule that is not replaced by common physiological anions. In addition, this ligand is highly selective for Gd(III) binding in the presence of Zn(II) or Ca(II). The symmetric charge distribution of the 1,2-HOPO chelates is associated with favorably long electronic relaxation time T1,2e comparable to those of GdDOTA. This, in addition to the fast water exchange rate typical of HOPO chelates, improves the relaxivity to r1p = 8.2 mM-1 s-1 (0.47 T). This remarkably high value is unprecedented for small-molecule, q = 1 MRI-CA.

Original languageEnglish
Pages (from-to)4796-4798
Number of pages3
JournalInorganic Chemistry
Volume46
Issue number12
DOIs
Publication statusPublished - 11 Jun 2007

Fingerprint

Dive into the research topics of 'Optimized relaxivity and stability of [Gd(H(2,2)-1,2-HOPO)(H 2O)]- for use as an MRI contrast agent'. Together they form a unique fingerprint.

Cite this