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arXiv · 1612.07694

Compression and reswelling of microgel particles after an osmotic shock

Jelle F. Sleeboom·Panayiotis Voudouris·Melle T. J. J. M. Punter·Frank J. Aangenendt·Daniel Florea·Paul van der Schoot·Hans M. Wyss
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Abstract

We use dedicated microfluidic devices to expose soft hydrogel particles to a rapid change in the externally applied osmotic pressure and observe a non-monotonic response: After an initial rapid compression the particle slowly reswells to approximately its original size. Using a simple phenomenological and a more elaborate poroelastic model, we extract important material properties from a single microfluidic experiment, including the compressive modulus, the gel permeability and the diffusivity of the osmolyte inside the gel. We expect our approach to be relevant to applications such as controlled release, chromatography, and responsive materials.

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Jelle F. Sleeboom, Panayiotis Voudouris, Melle T. J. J. M. Punter, Frank J. Aangenendt, Daniel Florea, Paul van der Schoot, Hans M. Wyss. 2016-12-22. Compression and reswelling of microgel particles after an osmotic shock. https://doi.org/10.1103/physrevlett.119.098001

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