Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 May 17;32(19):4917-23.
doi: 10.1021/acs.langmuir.5b03841. Epub 2016 May 3.

Modification of β-Sheet Forming Peptide Hydrophobic Face: Effect on Self-Assembly and Gelation

Mohamed A Elsawy, Andrew M Smith, Nigel Hodson, Adam Squires  1 , Aline F Miller, Alberto Saiani
Affiliations

Modification of β-Sheet Forming Peptide Hydrophobic Face: Effect on Self-Assembly and Gelation

Mohamed A Elsawy et al. Langmuir. .

Abstract

β-Sheet forming peptides have attracted significant interest for the design of hydrogels for biomedical applications. One of the main challenges is the control and understanding of the correlations between peptide molecular structure, the morphology, and topology of the fiber and network formed as well as the macroscopic properties of the hydrogel obtained. In this work, we have investigated the effect that functionalizing these peptides through their hydrophobic face has on their self-assembly and gelation. Our results show that the modification of the hydrophobic face results in a partial loss of the extended β-sheet conformation of the peptide and a significant change in fiber morphology from straight to kinked. As a consequence, the ability of these fibers to associate along their length and form large bundles is reduced. These structural changes (fiber structure and network topology) significantly affect the mechanical properties of the hydrogels (shear modulus and elasticity).

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing financial interest.

Figures

Figure 1
Figure 1
Top: schematic representation of the self-assembling and gelation processes of β-sheet forming peptides. Bottom left: schematic representation of an extended β-sheet fiber. Bottom right: molecular structures of F9 and FC9-BM.
Figure 2
Figure 2
Scheme of the synthetic route used to produce FC9-BM peptide.
Figure 3
Figure 3
Left: ATR-FTIR spectra obtained for F9/FC9-BM hybrid hydrogels with an overall peptide molar concentration of 30 mM. Right: 1624 cm–1 β-sheet peak relative intensity vs FC9-BM content.
Figure 4
Figure 4
CD spectra obtained for F9/FC9-BM solutions prepared by 20-fold dilution of hybrid hydrogels with overall peptide molar concentrations of 30 mM.
Figure 5
Figure 5
TEM (top) and AFM height (bottom) images obtained for the different samples. Arrows in the TEM of 100% FC9-BM show example of kinks in fibers (see text for further details).
Figure 6
Figure 6
Log vs log (left) and ln qI(q) vs q2 representation of the SAXS scattering pattern obtained for the 100% F9, 50% F9 + 50% FC9-BM, and 100% FC9-BM samples prepared at 3 mM concentration.
Figure 7
Figure 7
Left: shear modulus (G′) of F9/FC9-BM composite hydrogels at 15 Hz obtained from the frequency sweep experiments performed at 0.2% strain vs FC9-BM content. Right: strain sweep experiments for the 100% F9 (●, ○), 75% F9/25% FC9-BM (⧫, ◊), and 100% FC9-BM sample (■, □) (close symbols: G′; open symbols: G″). All samples had an overall peptide molar concentration of 30 mM.
Figure 8
Figure 8
Log–log plot of shear moduli (G′) vs molar concentrations obtained for F9 (●) and FC9-BM (○) hydrogels.
See this image and copyright information in PMC

References

    1. Haines-Butterick L.; Rajagopal K.; Branco M.; Salick D.; Rughani R.; Pilarz M.; Lamm M. S.; Pochan D. J.; Schneider J. P. Controlling hydrogelation kinetics by peptide design for three-dimensional encapsulation and injectable delivery of cells. Proc. Natl. Acad. Sci. U. S. A. 2007, 104 (19), 7791–7796. 10.1073/pnas.0701980104. - DOI - PMC - PubMed
    1. Yan C.; Mackay M. E.; Czymmek K.; Nagarkar R. P.; Schneider J. P.; Pochan D. J. Injectable Solid Peptide Hydrogel as a Cell Carrier: Effects of Shear Flow on Hydrogels and Cell Payload. Langmuir 2012, 28 (14), 6076–6087. 10.1021/la2041746. - DOI - PMC - PubMed
    1. Collier J. H.; Rudra J. S.; Gasiorowski J. Z.; Jung J. P. Multi-component extracellular matrices based on peptide self-assembly. Chem. Soc. Rev. 2010, 39 (9), 3413–3424. 10.1039/b914337h. - DOI - PMC - PubMed
    1. Szkolar L.; Guilbaud J. B.; Miller A. F.; Gough J. E.; Saiani A. Enzymatically triggered peptide hydrogels for 3D cell encapsulation and culture. J. Pept. Sci. 2014, 20 (7), 578–584. 10.1002/psc.2666. - DOI - PubMed
    1. Matson J. B.; Stupp S. I. Self-assembling peptide scaffolds for regenerative medicine. Chem. Commun. 2012, 48 (1), 26–33. 10.1039/C1CC15551B. - DOI - PMC - PubMed

Publication types