title: Thermodynamic stability and kinetic inertness of a Gd-DTPA bisamide complex grafted onto gold nanoparticles.
abstract: Gold nanoparticles coated by gadolinium (III) chelates (Au@DTDTPA) where DTDTPA is a dithiolated bisamide derivative of diethylenetriamine-N,N,N',N'',N''-pentaacetic acid (DTPA), constituted contrast agents for both X-ray computed tomography and magnetic resonance imaging. In an MRI context, highly stable Gd(3+) complexes are needed for in vivo applications. Thus, knowledge of the thermodynamic stability and kinetic inertness of these chelates, when grafted onto gold nanoparticles, is crucial since bisamide DTPA chelates are usually less suited for Gd(3+) coordination than DTPA. Therefore, these parameters were evaluated by means of potentiometric titrations and relaxivity measurements. The results showed that, when the chelates were grafted onto the nanoparticle, not only their thermodynamic stability but also their kinetic inertness were improved. These positive effects were correlated to the chelate packing at the nanoparticle surface that stabilized the corresponding Gd(3+) complexes and greatly enhanced their kinetic inertness.
authors.affiliation: Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, UFR des Sciences Exactes et Naturelles, Bâtiment 18, Europol'Agro, BP 1039, 51687, REIMS Cedex 2, France.
authors.forename: Vijetha
authors.initials: V
authors.lastname: Mogilireddy
authors.affiliation: Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, UFR des Sciences Exactes et Naturelles, Bâtiment 18, Europol'Agro, BP 1039, 51687, REIMS Cedex 2, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Déchamps-Olivier
authors.affiliation: Laboratoire de Physico-Chimie des Matériaux Luminescents, UMR CNRS 5620, Université Claude Bernard Lyon 1, 69622, Villeurbanne Cedex, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Alric
authors.affiliation: Institut UTINAM, UMR 6213 CNRS, Université de Franche-Comté, 25030, BESANCON, France.
authors.forename: Gautier
authors.initials: G
authors.lastname: Laurent
authors.affiliation: University of Mons-Hainaut, NMR and Molecular Imaging Laboratory, Department of General, Organic and Biomedical Chemistry, B-7000, Mons, Belgium.
authors.forename: Sophie
authors.initials: S
authors.lastname: Laurent
authors.affiliation: University of Mons-Hainaut, NMR and Molecular Imaging Laboratory, Department of General, Organic and Biomedical Chemistry, B-7000, Mons, Belgium.|Center for Microscopy and Molecular Imaging, 6041, Gosselies, Belgium.
authors.forename: Luce
authors.initials: L
authors.lastname: Vander Elst
authors.affiliation: University of Mons-Hainaut, NMR and Molecular Imaging Laboratory, Department of General, Organic and Biomedical Chemistry, B-7000, Mons, Belgium.|Center for Microscopy and Molecular Imaging, 6041, Gosselies, Belgium.
authors.forename: Robert
authors.initials: R
authors.lastname: Muller
authors.affiliation: Institut UTINAM, UMR 6213 CNRS, Université de Franche-Comté, 25030, BESANCON, France.
authors.forename: Rana
authors.initials: R
authors.lastname: Bazzi
authors.affiliation: Institut UTINAM, UMR 6213 CNRS, Université de Franche-Comté, 25030, BESANCON, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Roux
authors.affiliation: Laboratoire de Physico-Chimie des Matériaux Luminescents, UMR CNRS 5620, Université Claude Bernard Lyon 1, 69622, Villeurbanne Cedex, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Tillement
authors.affiliation: Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, UFR des Sciences Exactes et Naturelles, Bâtiment 18, Europol'Agro, BP 1039, 51687, REIMS Cedex 2, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Chuburu
mesh_terms: D002614:Chelating Agents; D003287:Contrast Media / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry; D019786:Gadolinium DTPA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D013816:Thermodynamics; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D002614:Chelating Agents; D003287:Contrast Media; D006046:Gold; D005682:Gadolinium; D019786:Gadolinium DTPA
keywords: gadolinium chelates; imaging agents; kinetics; nanoparticles; thermodynamics