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Redox-activated manganese-based MR contrast agent.

ABSTRACT: Here we report a simple Mn coordination complex with utility as a redox-sensitive MR probe. The HBET ligand stabilizes both the Mn(2+) and Mn(3+) oxidation states. In the presence of glutathione (GSH), low relaxivity Mn(III)-HBET is converted to high relaxivity Mn(II)-HBET with a 3-fold increase in relaxivity, and concomitant increase in MR signal. Alternately, hydrogen peroxide can convert Mn(II)-HBET to Mn(III)-HBET with a reduction in MR signal.

SUBMITTER: Loving GS

PROVIDER: S-EPMC3622546 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Redox-activated manganese-based MR contrast agent.

Loving Galen S GS Mukherjee Shreya S Caravan Peter P

Journal of the American Chemical Society 20130319 12

Here we report a simple Mn coordination complex with utility as a redox-sensitive MR probe. The HBET ligand stabilizes both the Mn(2+) and Mn(3+) oxidation states. In the presence of glutathione (GSH), low relaxivity Mn(III)-HBET is converted to high relaxivity Mn(II)-HBET with a 3-fold increase in relaxivity, and concomitant increase in MR signal. Alternately, hydrogen peroxide can convert Mn(II)-HBET to Mn(III)-HBET with a reduction in MR signal. ...[more]

PMID: 23510406

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