MRI contrast agents (CAs) are increasingly used in the medical field for sensitive imaging in vivo. However, the toxicity of some CAs, which must be present at a concentration to provide effective enhancement, poses a barricade to widespread use in vivo. Nanaoscale materials containing relaxivity-enhancing moieties provide an alternative chemical approach to achieving more sensitive and safer contrast agents. Moreover, they hold the promise of providing a mechanism for molecular targeting of materials in vivo for improved diagnostics. Herein, ring-opening metathesis polymerization (ROMP) is used to synthesize organic polymers terminated with a gadolinium chelate. These ROMP block copolymers were varied in amphiphilicity so that upon forming micellar nanoparticles in water, the chelate is located either on the shell of the particle or within the core. These materials were found to have extraordinarily elevated water relaxivity numbers. Using in vitro NMR techniques and microscopy, these unusually effective relaxivity enhancing CAs were characterized in order to fully understand the mechanism of relaxation.

Gadolinium labeled core- and shell-nanoparticles: Strategies toward improved MRI contrast agents

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.