Abstract
ABSTRACT
During this project new macrocyclic gadolinium (Gd (III)) complexes with a cationic side group were made as potential contrast agents for magnetic resonance imaging (MRI).
Two DO3A-derivates with a guanidine side group have been synthesized. In addition, synthesis of two DO3A- derivates with a permanent cationic quaternary ammonium side group was attempted.
This was done in order to study how the introduction of a cationic moiety into the MRI contrast agents will affect the distribution pattern in the body. All gadolinium based MRI contrast agents on the market today are either neutral or negatively charged, so a change in the distribution pattern would be expected when a cationic moiety was introduced.
Some problems with purification were seen during synthesis. At the end, efficient purification methods were not found, and therefore it was not possible to determine the relaxivities of the gadolinium complexes made, nor carry out biodistribution studies in rats. Both measurements require purified substances.