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A review of responsive MRI contrast agents: 2005-2014.

ABSTRACT: This review focuses on MRI contrast agents that are responsive to a change in a physiological biomarker. The response mechanisms are dependent on six physicochemical characteristics, including the accessibility of water to the agent, tumbling time, proton exchange rate, electron spin state, MR frequency or superparamagnetism of the agent. These characteristics can be affected by changes in concentrations or activities of enzymes, proteins, nucleic acids, metabolites, or metal ions, or changes in redox state, pH, temperature, or light. A total of 117 examples are presented, including ones that employ nuclei other than (1) H, which attests to the creativity of multidisciplinary research efforts to develop responsive MRI contrast agents.

SUBMITTER: Hingorani DV

PROVIDER: S-EPMC4414668 | biostudies-literature | 2015 Jul-Aug

REPOSITORIES: biostudies-literature

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A review of responsive MRI contrast agents: 2005-2014.

Hingorani Dina V DV Bernstein Adam S AS Pagel Mark D MD

Contrast media & molecular imaging 20141029 4

This review focuses on MRI contrast agents that are responsive to a change in a physiological biomarker. The response mechanisms are dependent on six physicochemical characteristics, including the accessibility of water to the agent, tumbling time, proton exchange rate, electron spin state, MR frequency or superparamagnetism of the agent. These characteristics can be affected by changes in concentrations or activities of enzymes, proteins, nucleic acids, metabolites, or metal ions, or changes in ...[more]

PMID: 25355685

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