A Janus Chelator Enables Biochemically Responsive MRI Contrast with Exceptional Dynamic Range.
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ABSTRACT:
SUBMITTER: Gale EM
PROVIDER: S-EPMC5328420 | biostudies-literature | 2016 Dec
REPOSITORIES: biostudies-literature
Publications
A Janus Chelator Enables Biochemically Responsive MRI Contrast with Exceptional Dynamic Range.
Gale Eric M EM Jones Chloe M CM Ramsay Ian I Farrar Christian T CT Caravan Peter P
Journal of the American Chemical Society 20161202 49
We introduce a new biochemically responsive Mn-based MRI contrast agent that provides a 9-fold change in relaxivity via switching between the Mn<sup>3+</sup> and Mn<sup>2+</sup> oxidation states. Interchange between oxidation states is promoted by a "Janus" ligand that isomerizes between binding modes that favor Mn<sup>3+</sup> or Mn<sup>2+</sup>. It is the only ligand that supports stable complexes of Mn<sup>3+</sup> and Mn<sup>2+</sup> in biological milieu. Rapid interconversion between oxidat ...[more]
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