title: Interfacial Ca2+environments in nanocrystalline apatites revealed by dynamic nuclear polarization enhanced43Ca NMR spectroscopy.
abstract: The interfaces within bones, teeth and other hybrid biomaterials are of paramount importance but remain particularly difficult to characterize at the molecular level because both sensitive and selective techniques are mandatory. Here, it is demonstrated that unprecedented insights into calcium environments, for example the differentiation of surface and core species of hydroxyapatite nanoparticles, can be obtained using solid-state NMR, when combined with dynamic nuclear polarization. Although calcium represents an ideal NMR target here (and de facto for a large variety of calcium-derived materials), its stable NMR-active isotope, calcium-43, is a highly unreceptive probe. Using the sensitivity gains from dynamic nuclear polarization, not only could calcium-43 NMR spectra be obtained easily, but natural isotopic abundance 2D correlation experiments could be recorded for calcium-43 in short experimental time. This opens perspectives for the detailed study of interfaces in nanostructured materials of the highest biological interest as well as calcium-based nanosystems in general.
authors.affiliation: Univ. Grenoble Alpes, INAC, F-38000 Grenoble, France.|CEA, INAC, F-38000 Grenoble, France.
authors.forename: Daniel
authors.identifier: 0000-0002-1015-0980
authors.initials: D
authors.lastname: Lee
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, Collège de France, UMR CNRS 7574, Laboratoire de Chimie de la Matière Condensée de Paris, 4 place Jussieu, 75252 Paris cedex 05, France.
authors.forename: César
authors.initials: C
authors.lastname: Leroy
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, Collège de France, UMR CNRS 7574, Laboratoire de Chimie de la Matière Condensée de Paris, 4 place Jussieu, 75252 Paris cedex 05, France.
authors.forename: Charlène
authors.initials: C
authors.lastname: Crevant
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, Collège de France, UMR CNRS 7574, Laboratoire de Chimie de la Matière Condensée de Paris, 4 place Jussieu, 75252 Paris cedex 05, France.
authors.forename: Laure
authors.initials: L
authors.lastname: Bonhomme-Coury
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, Collège de France, UMR CNRS 7574, Laboratoire de Chimie de la Matière Condensée de Paris, 4 place Jussieu, 75252 Paris cedex 05, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Babonneau
authors.affiliation: Institut Charles Gerhardt de Montpellier, UMR5253, CNRS UM ENSCM, CC1701, Place Eugène Bataillon, 34095 Montpellier cedex 05, France.
authors.forename: Danielle
authors.initials: D
authors.lastname: Laurencin
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, Collège de France, UMR CNRS 7574, Laboratoire de Chimie de la Matière Condensée de Paris, 4 place Jussieu, 75252 Paris cedex 05, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Bonhomme
authors.affiliation: Univ. Grenoble Alpes, INAC, F-38000 Grenoble, France.|CEA, INAC, F-38000 Grenoble, France.
authors.forename: Gaël
authors.initials: G
authors.lastname: De Paëpe