Nuclear spin relaxation study of aqueous raffinose solution in the presence of a gadolinium contrast agent

✍ Scribed by Leila Ghalebani; Danuta Kruk; Jozef Kowalewski

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 109 KB
• Volume: 43
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1535

✦ Synopsis

Abstract

Paramagnetic enhancement of nuclear spin–lattice relaxation rates (PREs) was measured in aqueous solution of the trisaccharide raffinose in the presence of a gadolinium(III) complex, GdDTPA–BMA, used as a magnetic resonance imaging contrast agent. The relaxation enhancement of aqueous protons was measured over a broad range of magnetic fields, using field‐cycling apparatus in addition to conventional spectrometers. The nuclear magnetic relaxation dispersion profile thus obtained was interpreted with a recently developed model, allowing for both inner‐ and outer‐sphere relaxation. The relaxation enhancement for the carbon‐13 nuclei in raffinose was studied under high‐resolution conditions at three magnetic fields, whereas the sugar proton PRE was measured at two fields. The PRE of the sugar nuclei could be interpreted in a consistent way, assuming that it was caused by the outer‐sphere mechanism. The electron spin relaxation was found to be a less important source of modulation of the electron–nuclear dipole–dipole interaction than the mutual translational diffusion. Copyright © 2004 John Wiley & Sons, Ltd.