Natural abundance 43Ca solid-state NMR characterization of hydroxyapatite: identification of the two calcium sites

Danielle Laurencin (1) , Alan Wong (1) , Ray Dupree (1) , Mark E. Smith (1)

1 University of Warwick [Coventry]

Natural abundance 43Ca solid-state NMR of hydroxyapatite (Ca10(PO4)6(OH)2) was performed at three different fields (8.45, 14.1 and 18.8 T). The two crystallographically distinct calcium sites of the apatite structure were spectroscopically resolved at 18.8 T. The 43Ca NMR interaction parameters (delta iso, Cq and hq) of each site were determined by multiple magnetic-field simulations. The peaks with delta iso = 11.2 +- 0.8 and -1.8 +- 0.8 ppm, both with Cq = 2.6 +- 0.4 MHz, were assigned to the Ca(II) and Ca(I) sites, respectively, on the basis of their relative intensities.

Mots clés: hydroxyapatite; RMN du solide 43Ca; RMN des noyaux à bas-gamma

Domaines: Chimie inorganique; Matériaux

Danielle Laurencin, Alan Wong, Ray Dupree, Mark E. Smith. Natural abundance 43Ca solid-state NMR characterization of hydroxyapatite: identification of the two calcium sites. Magnetic Resonance in Chemistry, 2008, 46 (4), pp.347-350. ⟨10.1002/mrc.2117⟩. ⟨hal-00358171⟩