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arXiv · 1209.0032

Capillary micromechanics: Measuring the elasticity of microscopic soft objects

Hans M. Wyss·Thomas Franke·Elisa Mele·David A. Weitz
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Abstract

We present a simple method for accessing the elastic properties of microscopic deformable particles. This method is based on measuring the pressure-induced deformation of soft particles as they are forced through a tapered glass microcapillary. It allows us to determine both the compressive and the shear modulus of a deformable object in one single experiment. Measurements on a model system of poly-acrylamide microgel particles exhibit excellent agreement with measurements on bulk gels of identical composition. Our approach is applicable over a wide range of mechanical properties and should thus be a valuable tool for the characterization of a variety of soft and biological materials.

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Hans M. Wyss, Thomas Franke, Elisa Mele, David A. Weitz. 2012-08-31. Capillary micromechanics: Measuring the elasticity of microscopic soft objects. https://doi.org/10.1039/c003344h

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