Heteroditopic Binding of Magnetic Resonance Contrast Agents for Increased Relaxivity

Authors

  • Dr. Zhaoda Zhang,

    1. A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th St, Suite 2301, Charlestown, MA 02129 (USA), Fax: (+1) 617-726-7422
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  • Dr. Andrew F. Kolodziej,

    1. Epix Pharmaceuticals, Lexington, MA 02124 (USA)
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  • Matthew T. Greenfield,

    1. Epix Pharmaceuticals, Lexington, MA 02124 (USA)
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  • Prof. Peter Caravan

    Corresponding author
    1. A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th St, Suite 2301, Charlestown, MA 02129 (USA), Fax: (+1) 617-726-7422
    • A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149 13th St, Suite 2301, Charlestown, MA 02129 (USA), Fax: (+1) 617-726-7422
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  • This work was supported in part by the National Institute of Biomedical Imaging and Bioengineering, R01EB009062.

Abstract

original image

Kept within bounds: For peptide-targeted contrast agents, internal motion limits the relaxivity gain. A focused library approach identified an N-terminal thymine peptide nucleic acid (PNA) that reaches an additional binding pocket on the protein fibrin. The heteroditopic binding rigidifies the molecule upon binding, resulting in increased protein-bound relaxivity (see picture).

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