| abstract |
Disclosed herein are complexes of gadolinium metal, ligand and meglumine that are substantially free of non-aqueous solvents. In particular, solvent-free complexes of 1) gadopentetate dimeglumine and 2) gadoterate meglumine are disclosed and methods of their preparation are disclosed. In addition, methods are disclosed for purifying reactants, monitoring and controlling pH, quantifying the free gadolinium content, quantifying the concentration of gadolinium-ligand complex in aqueous solution, and procedures for producing a drug product in one step. The one step process eliminates the need to dry the gadolinium-ligand complex, which is typically highly hygroscopic. The one step process includes purification steps that do not require the use of non-aqueous solvents. |