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Time-resolved dehydration-induced structural changes in an intact bovine cortical bone revealed by solid-state NMR
Peizhi Zhu1, Jiadi Xu, Nadder Sahar
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Journal of the American Chemical Society
|November 10, 2009
Summary
Dehydration causes bone
Area of Science:
- Biomaterials Science
- Structural Biology
- Biophysics
Background:
- Bone's complex hierarchical structure presents challenges for atomic-level analysis.
- Dehydration is known to impair bone's mechanical properties, but the structural basis is unclear.
Purpose of the Study:
- To investigate dehydration-induced structural changes in intact bovine cortical bone at the atomic level.
- To elucidate the role of water in bone's structure and mechanics.
Main Methods:
- Utilized solid-state Nuclear Magnetic Resonance (NMR) spectroscopy.
- Employed controlled dehydration and Hydrogen-Deuterium (H/D) exchange techniques.
- Analyzed proton ((1)H) and carbon-13 ((13)C) NMR spectra under magic-angle spinning.
Main Results:
- Observed slow denaturation of collagen upon dehydration.
- Confirmed that the trans-Xaa-Pro conformation in collagen remains stable.
- Hypothesized that glycosaminoglycans chelate Ca(2+) ions on the mineral surface via sulfate or carboxylate groups.
Conclusions:
- Water molecules play a critical role in maintaining bone's structural integrity.
- Structural changes induced by dehydration impact bone's mechanical properties.
- Findings offer insights into the bone's structure-mechanics relationship.
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