Structural and Dynamic Parameters Obtained from 17O NMR, EPR, and NMRD Studies of Monomeric and Dimeric Gd3+ Complexes of Interest in Magnetic Resonance Imaging: An Integrated and Theoretically Self-Consistent Approach1

摘要: We present the results of new and previously published 17O NMR, EPR, NMRD studies aqueous solutions Gd3+ octaaqua ion commercial MRI contrast agents [Gd(DTPA)(H2O)]2- (MAGNEVIST, Schering AG, DTPA = 1,1,4,7,7-pentakis(carboxymethyl)-1,4,7-triazaheptane), [Gd(DTPA-BMA)(H2O)] (OMNISCAN, Sanofi Nycomed, DTPA-BMA 1,7-bis[(N-methylcarbamoyl)methyl]-1,4,7-tris(carboxymethyl)-1,4,7-triazaheptane), [Gd(DOTA)(H2O)]- (DOTAREM, Guerbet, DOTA 1,4,7,10-tetrakis(carboxymethyl)-1,4,7,10-tetraazacyclododecane). High-field EPR measurements at different concentrations give evidence an intermolecular dipole−dipole electronic relaxation mechanism that has not been described for complexes. For first time, experimental data from three techniques each complex have treated using a self-consistent theoretical model in simultaneous multiple parameter least-squares fitting procedure. The lower quality fits compared to separate o...