Synthesis and Physicolchemical Studies of Lanthanide and Transition Metal Chelates of Relevance to Magnetic Resonance Imaging

• Research unit: COST
• Project number: C93.0027

Key words (English)

MRI; metal chelates; NMR; EPR

Research programs (English)

COST-Action D1 - Biocoordination chemistry

Short description (English)

See abstract

Further information (English)

Full name of research-institution/enterprise: EPF Lausanne Laboratoire de Chimie Inorganique et Bioinorganique EPFL - FSB/ISIC - LCIB

Abstract (English)

We have shown that 17O NMR is a useful method to determinate water exchange rate on Gd(III) complexes, as one of the essential parameters influencing efficacy of contrast agents. Variable pressure 17O NMR helped us understand the exchange mechanism. A comparison of numerous monomer, dimer and polymer Gd(III) polyamino-polycarboxylate complexes has revealed which structural factors affect water exchange rates. Multiple field EPR measurements allowed for deeper insight into electronic relaxation. We have introduced an integrated data treatment for the three principal techniques (17O NMR, EPR and NMRD) that are used to determine parameters influencing proton relaxivity. Molecular dynamic calculations have been established for lanthanide(III) complexes, and have already proven to be useful for aqua ions in the elucidation of electronic relaxation and water exchange processes. The knowledge obtained during the last four years has shown how to modifiy the ligand structure in order to improve the contrast agent's performance.

References in databases (English)

Swiss Database: COST-DB of the State Secretariat for Education and Research Hallwylstrasse 4 CH-3003 Berne, Switzerland Tel. [phone] Swiss Project-Number: C93.0027