title: 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.
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, USA.
authors.forename: Dina V
authors.initials: DV
authors.lastname: Hingorani
authors.affiliation: Department of Biomedical Engineering, University of Arizona, USA.
authors.forename: Adam S
authors.initials: AS
authors.lastname: Bernstein
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, USA.|Department of Biomedical Engineering, University of Arizona, USA.|Department of Medical Imaging, University of Arizona, USA.|University of Arizona Cancer Center, University of Arizona, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Pagel
mesh_terms: D003287:Contrast Media / Q000737:chemistry* / Q000627:therapeutic use*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: CEST agents; MRI contrast agents; MRS agents; T1 agents; T2* agents; hyperpolarized agents; responsive agents