Role of sheet-edge interactions in β-sheet self-assembling peptide hydrogels

DOI: 10.1021/acs.biomac.0c00229

Authors: Jacek K. Wychowaniec (The University of Manchester) , Andrew Smith (The University of Manchester) , Cosimo Ligorio (The University of Manchester) , Oleksandr O. Mykhaylyk (The University of Sheffield) , Aline F. Miller (The University of Manchester) , Alberto Saiani (The University of Manchester)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Biomacromolecules

State: Published (Approved)
Published: April 2020
Diamond Proposal Number(s): 12950 , 15246

Abstract: Hydrogels’ hydrated fibrillar nature makes them the material of choice for the design and engineering of 3D-scaffolds for cell culture, tissue engineering and drug delivery applications. One particular class of hydrogels that has been the focus of significant research is self-assembling peptide hydrogels. In the present work we were interested in exploring how fibre-fibre edge interactions affect the self-assembly and gelation properties of amphipathic peptides. For this purpose we investigated two β-sheet forming peptides, FEFKFEFK (F8) and KFEFKFEFKK (KF8K), the latter one having the fibre edges covered by lysine residues. Our results showed that the addition of the two lysine residues did not affect the ability of the peptides to form β-sheet rich fibres provided that the overall charge carried by the two peptides was kept constant. It did though significantly reduce edge driven hydrophobic fibre-fibre associative interactions resulting in a reduced tendency for KF8K fibres to associate / aggregate laterally and form large fibre bundles and consequently network crosslinks. This effect resulted in the formation of hydrogels with lower moduli but faster dynamics. As a result KF8K fibres could be aligned only under high shear and at high concentration while F8 hydrogel fibres were found to align readily at low shear and low concentration. In addition F8 hydrogels were found to fragment at high concentration due to the high aggregation state stabilising the fibre bundles resulting in fibre breakage rather than disentanglement and alignment.

Journal Keywords: Peptide; nano-fibres; hydrogel; Beta-sheet; self-assembly; shear thinning; SIPLI

Subject Areas: Biology and Bio-materials, Chemistry, Medicine


Instruments: I22-Small angle scattering & Diffraction

Added On: 14/04/2020 10:10

Documents:
acs.biomac.0c00229.pdf

Discipline Tags:

Drug Delivery Biotech & Biological Systems Health & Wellbeing Soft condensed matter physics Chemistry Chemical Engineering Engineering & Technology Life Sciences & Biotech

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS)