title: Molecular imaging using a targeted magnetic resonance hyperpolarized biosensor.
abstract: A magnetic resonance approach is presented that enables high-sensitivity, high-contrast molecular imaging by exploiting xenon biosensors. These sensors link xenon atoms to specific biomolecular targets, coupling the high sensitivity of hyperpolarized nuclei with the specificity of biochemical interactions. We demonstrated spatial resolution of a specific target protein in vitro at micromolar concentration, with a readout scheme that reduces the required acquisition time by >3300-fold relative to direct detection. This technique uses the signal of free hyperpolarized xenon to dramatically amplify the sensor signal via chemical exchange saturation transfer (CEST). Because it is approximately 10,000 times more sensitive than previous CEST methods and other molecular magnetic resonance imaging techniques, it marks a critical step toward the application of xenon biosensors as selective contrast agents in biomedical applications.
authors.affiliation: Department of Chemistry, University of California, Berkeley, CA 94720, USA. dewemmer@lbl.gov
authors.forename: Leif
authors.initials: L
authors.lastname: Schröder
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Lowery
authors.forename: Christian
authors.initials: C
authors.lastname: Hilty
authors.forename: David E
authors.initials: DE
authors.lastname: Wemmer
authors.forename: Alexander
authors.initials: A
authors.lastname: Pines
mesh_terms: D001360:Avidin; D015374:Biosensing Techniques; D001710:Biotin; D003287:Contrast Media; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008863:Microspheres; D012680:Sensitivity and Specificity; D012685:Sepharose; D013997:Time Factors; D014979:Xenon Isotopes
chemical_list: D003287:Contrast Media; D014979:Xenon Isotopes; C066402:avidin-agarose; D001360:Avidin; D001710:Biotin; D012685:Sepharose