Elucidation of differential mineralisation on native and regenerated silk matrices
File(s)Midha_et_al_MSE_C_2016_as_submitted.pdf (12.34 MB)
Accepted version
Author(s)
Midha, S
Tripathi, R
Geng, H
Lee, PD
Ghosh, S
Type
Journal Article
Abstract
Bone mineralisation is a well-orchestrated procedure triggered by a protein-based template inducing the nucleation of hydroxyapatite (HA) nanocrystals on the matrix. In an attempt to fabricate superior nanocomposites from silk fibroin, textile braided structures made of natively spun fibres of Bombyx mori silkworm were compared against regenerated fibroin (lyophilized and films) underpinning the influence of intrinsic properties of fibroin matrices on HA nucleation. We found that native braids could bind Ca(2+) ions through electrostatic attraction, which initiated the nucleation and deposition of HA, as evidenced by discrete shift in amide peaks via ATR-FTIR. This phenomenon also suggests the involvement of amide linkages in promoting HA nucleation on fibroin. Moreover, CaCl2-SBF immersion of native braids resulted in preferential growth of HA along the c-axis, forming needle-like nanocrystals and possessing Ca/P ratio comparable to commercial HA. Though regenerated lyophilized matrix also witnessed prominent peak shift in amide linkages, HA growth was restricted to (211) plane only, albeit at a significantly lower intensity than braids. Regenerated films, on the other hand, provided no crystallographic evidence of HA deposition within 7days of SBF immersion. The present work sheds light on the primary fibroin structure of B. mori which probably plays a crucial role in regulating template-induced biomineralisation on the matrix. We also found that intrinsic material properties such as surface roughness, geometry, specific surface area, tortuosity and secondary conformation exert influence in modulating the extent of mineralisation. Thus our work generates useful insights and warrants future studies to further investigate the potential of bone mimetic, silk/mineral nanocomposite matrices for orthopaedic applications.
Date Issued
2016-06-14
Date Acceptance
2016-06-12
Citation
Materials Science and Engineering C, 2016, 68, pp.663-674
ISSN
1873-0191
Publisher
Elsevier
Start Page
663
End Page
674
Journal / Book Title
Materials Science and Engineering C
Volume
68
Copyright Statement
© 2016 Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Subjects
Hydroxyapatite
Mineralisation
Silk fibroin
Simulated body fluid
Textile braid
Biomedical Engineering
0903 Biomedical Engineering
Publication Status
Published