Kinetics of1H →31P NMR cross-polarization in bone apatite and its mineral standards
| Autor: | Agnieszka Kaflak, Waclaw Kolodziejski |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Calcium Phosphates
Magnetic Resonance Spectroscopy Kinetics Carbonates Analytical chemistry Mineralogy Bone and Bones Apatite law.invention Crystal law Apatites medicine Magic angle spinning Humans General Materials Science Calcination Brushite Bone mineral Chemistry Phosphorus Isotopes Water General Chemistry Durapatite medicine.anatomical_structure visual_art visual_art.visual_art_medium Cortical bone Protons |
| Zdroj: | Magnetic Resonance in Chemistry. 46:335-341 |
| ISSN: | 1097-458X 0749-1581 |
| DOI: | 10.1002/mrc.2207 |
| Popis: | Kinetics of NMR cross-polarization (CP) from protons to phosphorus-31 nuclei was studied in the following samples: mineral of whole human bone, apatite prepared from bone, natural brushite, synthetic hydroxyapatite (hydrated and calcined), and synthetic carbonatoapatite of type B with 9 wt% of CO32−. In order to avoid an effect of magic angle spinning on CP and relaxation, the experiments were carried out on static samples. Parameters of the CP kinetics were discussed for trabecular and cortical bone tissue from adult subjects in comparison to the synthetic mineral standards. It was found that carbonatoapatite shows similar CP behavior to the bone mineral. Both materials undergo two-component CP kinetics. The fast-relaxing classical component is from the surface of apatite crystals and the slow-relaxing nonclassical component comes from the crystal interior. The components have been unambiguously assigned using inverse CP from phosphorus-31 to protons. The study provides information on a structured water layer, which covers crystal surface of carbonato- and bone apatite. The layer encompasses ca 40% of apatite phosphorus and its thickness is more than ca 2 nm. Copyright © 2008 John Wiley & Sons, Ltd. |
| Databáze: | OpenAIRE |
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