title: A responsive europium(III) chelate that provides a direct readout of pH by MRI.
abstract: A europium(III) DO3A-tris(amide) complex is reported for imaging pH by MRI using ratiometric chemical exchange saturation transfer (CEST) principles. Deprotonation of a single phenolic proton between pH 6 and 7.6 results in an ∼5 ppm shift in the water exchange CEST peak that is easily detected by MRI. Collection of two CEST images at two slightly different activation frequencies provides a direct readout of solution pH without the need of a concentration marker.
authors.affiliation: Department of Chemistry, University of Texas at Dallas, P.O. Box 830668, Richardson, Texas 75083, USA.
authors.forename: Yunkou
authors.initials: Y
authors.lastname: Wu
authors.forename: Todd C
authors.initials: TC
authors.lastname: Soesbe
authors.forename: Garry E
authors.initials: GE
authors.lastname: Kiefer
authors.forename: Piyu
authors.initials: P
authors.lastname: Zhao
authors.forename: A Dean
authors.initials: AD
authors.lastname: Sherry
mesh_terms: D002614:Chelating Agents / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008279:Magnetic Resonance Imaging / Q000379:methods*
chemical_list: D002614:Chelating Agents; D005063:Europium