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Title: Chirality-Mediated Mechanical and Structural Properties of Oligopeptide Hydrogels

Abstract

The origin and the effects of homochirality in the biological world continuously stimulate numerous hypotheses and much debate. This work attempts to look at the biohomochirality issue from a different angle - the mechanical properties of the bulk biomaterial and their relation to nanoscale structures. Using a pair of oppositely charged peptides that co-assemble into hydrogels, we systematically investigated the effect of chirality on the mechanical properties of these hydrogels through different combinations of syndiotactic and isotactic peptides. It was found that homochirality confers mechanical advantage, resulting in a higher elastic modulus and strain yield value. Yet, heterochirality confers kinetic advantage, resulting in faster gelation. Structurally, both homochiral and heterochiral hydrogels are made of fibers interconnected by lappet-like webs, but the homochiral peptide fibers are thicker and denser. These results highlight the possible role of biohomochirality in the evolution and/or natural selection of biomaterials.

Authors:
; ; ; ;  [1];  [2]
  1. (NIST)
  2. (
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Institutes of Health (NIH)
OSTI Identifier:
1048563
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chem. Mater.; Journal Volume: 24; Journal Issue: (12) ; 06, 2012
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRALITY; FIBERS; GELATION; HYDROGELS; KINETICS; MECHANICAL PROPERTIES; NEUTRONS; ORIGIN; PEPTIDES; SCATTERING; SPECTROSCOPY; STRAINS

Citation Formats

Taraban, Marc B., Feng, Yue, Hammouda, Boualem, Hyland, Laura L., Yu, Y. Bruce, and Maryland). Chirality-Mediated Mechanical and Structural Properties of Oligopeptide Hydrogels. United States: N. p., 2012. Web. doi:10.1021/cm300422q.
Taraban, Marc B., Feng, Yue, Hammouda, Boualem, Hyland, Laura L., Yu, Y. Bruce, & Maryland). Chirality-Mediated Mechanical and Structural Properties of Oligopeptide Hydrogels. United States. doi:10.1021/cm300422q.
Taraban, Marc B., Feng, Yue, Hammouda, Boualem, Hyland, Laura L., Yu, Y. Bruce, and Maryland). 2012. "Chirality-Mediated Mechanical and Structural Properties of Oligopeptide Hydrogels". United States. doi:10.1021/cm300422q.
@article{osti_1048563,
title = {Chirality-Mediated Mechanical and Structural Properties of Oligopeptide Hydrogels},
author = {Taraban, Marc B. and Feng, Yue and Hammouda, Boualem and Hyland, Laura L. and Yu, Y. Bruce and Maryland)},
abstractNote = {The origin and the effects of homochirality in the biological world continuously stimulate numerous hypotheses and much debate. This work attempts to look at the biohomochirality issue from a different angle - the mechanical properties of the bulk biomaterial and their relation to nanoscale structures. Using a pair of oppositely charged peptides that co-assemble into hydrogels, we systematically investigated the effect of chirality on the mechanical properties of these hydrogels through different combinations of syndiotactic and isotactic peptides. It was found that homochirality confers mechanical advantage, resulting in a higher elastic modulus and strain yield value. Yet, heterochirality confers kinetic advantage, resulting in faster gelation. Structurally, both homochiral and heterochiral hydrogels are made of fibers interconnected by lappet-like webs, but the homochiral peptide fibers are thicker and denser. These results highlight the possible role of biohomochirality in the evolution and/or natural selection of biomaterials.},
doi = {10.1021/cm300422q},
journal = {Chem. Mater.},
number = (12) ; 06, 2012,
volume = 24,
place = {United States},
year = 2012,
month =
}
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