Bhattacharya, S. orcid.org/0000-0001-7285-453X and Dubey, D.K. orcid.org/0000-0003-1264-1422 (2021) Radial variations in mechanical behaviour and fibrillar structure in annulus fibrosus has foundations at molecular length-scale: Insights from molecular dynamics simulations of type I and type II collagen molecules. Journal of Materials Research, 36 (17). pp. 3407-3425. ISSN 0884-2914
Abstract
In annulus fibrosus (AF), type I collagen (Col-I) dominates outer AF (OAF) while type II collagen (Col-II) dominates inner AF (IAF). Using molecular dynamics simulations, this work reports how molecular-level structural and mechanical differences between Col-I and Col-II contribute to AF exhibiting radially varying structure and mechanical properties. Results show that differences in interpolypeptide forces and residue solvent accessibility contributes to Col-I showing intact triple-helix, lower backbone kinks and interpolypeptide separation (IPS), and thus contributing to expression of lower intermolecular spacing in collagen fibrils, lower lamellae thickness and lower water content in OAF. Furthermore, Col-I primarily exhibits backbone stretch while Col-II exhibit backbone straightening under tension, despite having comparable elastic moduli of ~ 3.5 GPa and ~ 3.2 GPa during backbone stretch. Such differences contribute to OAF showing stiffer stress–strain characteristics under tension. Furthermore, higher slenderness ratio of Col-I leads to buckling under compression—contributing to larger radial bulge being exhibited by OAF lamellae.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Keywords: | Nanoscale, Biomaterial, Molecular, Stress/strain relationship, Tissue |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Mechanical Engineering (Leeds) > Institute of Medical and Biological Engineering (iMBE) (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 16 Feb 2024 10:22 |
Last Modified: | 16 Feb 2024 10:22 |
Status: | Published |
Publisher: | Springer |
Identification Number: | 10.1557/s43578-021-00376-2 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:209253 |