title: Gd(III) complexes intercalated into hydroxy double salts as potential MRI contrast agents.
abstract: The ion exchange intercalation of two Gd-based magnetic resonance imaging contrast agents into hydroxy double salts (HDSs) is reported. The presence of Gd(3+) diethylenetriaminepentaacetate and Gd(3+) diethylenetriaminepenta(methylenephosphonate) complexes in the HDS lattice after intercalation was confirmed by microwave plasma-atomic emission spectroscopy. The structural aspects of the HDS-Gd composites were studied by X-ray diffraction, with the intercalates having an interlayer spacing of 14.5-18.6 Å. Infrared spectroscopy confirmed the presence of characteristic vibration peaks associated with the Gd(3+) complexes in the intercalation compounds. The proton relaxivities of the Gd(3+) complex-loaded composites were 2 to 5-fold higher in longitudinal relaxivity, and up to 10-fold higher in transverse relaxivity, compared to solutions of the pure complexes. These data demonstrate that the new composites reported here are potentially potent MRI contrast agents.
authors.affiliation: UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK. g.williams@ucl.ac.uk.
authors.forename: Miao
authors.initials: M
authors.lastname: Jin
authors.forename: Dominic E M
authors.initials: DE
authors.lastname: Spillane
authors.forename: Carlos F G C
authors.initials: CF
authors.lastname: Geraldes
authors.forename: Gareth R
authors.initials: GR
authors.lastname: Williams
authors.forename: S W Annie
authors.initials: SW
authors.lastname: Bligh
mesh_terms: D003287:Contrast Media / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry*; D019786:Gadolinium DTPA / Q000737:chemistry; D008279:Magnetic Resonance Imaging; D009943:Organophosphorus Compounds / Q000737:chemistry; D012492:Salts
chemical_list: D003287:Contrast Media; D056831:Coordination Complexes; D009943:Organophosphorus Compounds; D012492:Salts; C042719:diethylenetriaminepenta(methylenephosphonic) acid; D005682:Gadolinium; D019786:Gadolinium DTPA