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Calcium ions to cross-link supramolecular nanofibers to tune the elasticity of hydrogels over orders of magnitude.

ABSTRACT: Learning from the stabilization of protein structures, we combine aromatic-aromatic and electrostatic interactions to tailor the elasticity of supramolecular hydrogels. Specifically, calcium ions allow interfiber cross-links among the supramolecular nanofibers of small peptides that consist of multiple carboxylic acid and aromatic groups. A small change in the concentration of calcium increases the elasticity of hydrogels over several orders of magnitude. This simple approach not only demonstrates a biomimetic design of materials but also confirms that the combination of multiple aromatic-aromatic interactions and multiple calcium salt bridges is a feasible way to control the mechanical properties of soft nanomaterials.

SUBMITTER: Shi J

PROVIDER: S-EPMC3238096 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Calcium ions to cross-link supramolecular nanofibers to tune the elasticity of hydrogels over orders of magnitude.

Shi Junfeng J Gao Yuan Y Zhang Ye Y Pan Yue Y Xu Bing B

Langmuir : the ACS journal of surfaces and colloids 20111102 23

Learning from the stabilization of protein structures, we combine aromatic-aromatic and electrostatic interactions to tailor the elasticity of supramolecular hydrogels. Specifically, calcium ions allow interfiber cross-links among the supramolecular nanofibers of small peptides that consist of multiple carboxylic acid and aromatic groups. A small change in the concentration of calcium increases the elasticity of hydrogels over several orders of magnitude. This simple approach not only demonstrat ...[more]

PMID: 21978281

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