Insulin Hexamer-Caged Gadolinium Ion as MRI Contrast-o-phore.

ABSTRACT: High-relaxivity protein-complexes of Gd^III are being pursued as MRI contrast agents in hope that they can be used at much lower doses that would minimize toxic-side effects of Gd^III release from traditional contrast agents. We construct here a new type of protein-based MRI contrast agent, a proteinaceous cage based on a stable insulin hexamer in which Gd^III is captured inside a water filled cavity. The macromolecular structure and the large number of "free" Gd^III coordination sites available for water binding lead to exceptionally high relaxivities per one Gd^III ion. The Gd^III slowly diffuses out of this cage, but this diffusion can be prevented by addition of ligands that bind to the hexamer. The ligands that trigger struct

SUBMITTER: Taylor SK 

PROVIDER: S-EPMC6347121 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature