Solid-state NMR has been applied to the study of two types of heterogeneous materials: bone and polymer-clay nanocomposites. Each has useful and unexpected properties that are largely determined by the interfacial region between the two components making up each material rationalization of these properties at a molecular level is essential if we are to intelligently design new materials, which might mimic bone for instance. In Chapter 3. 2D experiments that correlate the <i>T</i><sub>1</sub> relaxation time by the chemical shift are described and their application to the study of the interfacial region in Fe<sup>3+</sup> substituted polymer-clay nanocomposites is described. It is found that in polyhydroxyethylmethacrylate nanocomposites the polymer is significantly more ordered at the surface than in polymethylmethacrylate nanocomposites. In Chapter 5, a variety of techniques that explicit the dipolar coupling between <sup>31</sup>P in the inorganic phase and <sup>13</sup>C in the organic matrix of equine bone are used, with the aim of identifying the proteins and/or the amino acid residues responsible for the binding of the two phases and the nature of the interaction between the phases. Natural equine bone samples (i.e. non-isotopically enriched) are studied to give the first experimental evidence that (i) it is predominantly glutamate residues that are bound to the inorganic surface with a <i>d-</i><sup>13</sup>C-<sup>31</sup>P distance in the range 0.45-0.5 nm. (ii) no P-O-C bonds occur and (iii) that proline and hydroxyproline are not involved in binding. Finally, in Chapter 6, solid-state NMR is applied to the study of osteoarthritic equine bone samples with a view to characterizing the changes in bone composition and structure that occur with this disease.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:599750 |
| Date | January 2005 |
| Creators | Groom, N. S. |
| Publisher | University of Cambridge |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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