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Cited by 29Hydrogels: synthesis, properties, applicationsCellular Mechanics and InteractionsAdvanced Materials and Mechanics

Determination by Relaxation Tests of the Mechanical Properties of Soft Polyacrylamide Gels Made for Mechanobiology Studies

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Pérez-Calixto, Daniel, Amat-Shapiro, Samuel, Zamarrón-Hernández, Diego, Vázquez-Victorio, Genaro, Puech, Pierre-Henri, Hautefeuille, Mathieu·2021·Polymers
DOI 10.3390/polym13040629PMC PMC7923444

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Abstract

Following the general aim of recapitulating the native mechanical properties of tissues and organs in vitro, the field of materials science and engineering has benefited from recent progress in developing compliant substrates with physical and chemical properties similar to those of biological materials. In particular, in the field of mechanobiology, soft hydrogels can now reproduce the precise range of stiffnesses of healthy and pathological tissues to study the mechanisms behind cell responses to mechanics. However, it was shown that biological tissues are not only elastic but also relax at different timescales. Cells can, indeed, perceive this dissipation and actually need it because it is a critical signal integrated with other signals to define adhesion, spreading and even more complicated functions. The mechanical characterization of hydrogels used in mechanobiology is, however, commonly limited to the elastic stiffness (Young’s modulus) and this value is known to depend greatly on the measurement conditions that are rarely reported in great detail. Here, we report that a simple relaxation test performed under well-defined conditions can provide all the necessary information for characterizing soft materials mechanically, by fitting the dissipation behavior with a generalized Maxwell model (GMM). The simple method was validated using soft polyacrylamide hydrogels and proved to be very useful to readily unveil precise mechanical properties of gels that cells can sense and offer a set of characteristic values that can be compared with what is typically reported from microindentation tests.

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Authors
Pérez-Calixto, D., Amat-Shapiro, S., Zamarrón-Hernández, D., Vázquez-Victorio, G., Puech, P.-H., & Hautefeuille, M.
Affiliations
  • Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
  • Universidad Nacional Autónoma de México (MX)
  • Centre National de la Recherche Scientifique (FR)
Corresponding author
Hautefeuille, Mathieu
ORCID
Venue
Polymers
Publisher
MDPI AG
Published
2021-02-20
Volume
13
Issue
4
Pages
629
ISSN
2073-4360 (ISSN-L)
DOI
10.3390/polym13040629
PMC
PMC7923444
OpenAlex
W3122508512
Cited by
29
References
2
Citations by year
2026: 4 · 2025: 5 · 2024: 9 · 2023: 8 · 2022: 3
FWCI
1.59
Type
journal article
Language
en
Open access
Licence
Locations
  • Polymers (publishedVersion, cc-by)
  • Preprints.org (acceptedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • HAL (submittedVersion, other-oa)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México (IT102017, IN223621)
  • Centre National de la Recherche Scientifique (PICS project FibroSension (PICS07865))
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Medicine › Hydrogels: synthesis, properties, applications
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Cellular Mechanics and Interactions
  • Physical Sciences › Engineering › Mechanical Engineering › Advanced Materials and Mechanics
Keywords
polyacrylamide hydrogel, soft hydrogels, mechanical relaxation, energy dissipation, generalized Maxwell model, viscoelasticity, mechanobiology, cell mechanosensing, compliant substrates, Young's modulus, tissue stiffness

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