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arXiv · 1106.3980

Interactions between colloids induced by a soft cross-linked polymer substrate

Lorenzo Di Michele·Taiki Yanagishima·Anthony R. Brewer·Jurij Kotar·Seth Fraden·Erika Eiser
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Abstract

Using video-microscopy imaging we demonstrate the existence of a short-ranged equilibrium attraction between heavy silica colloids diffusing on soft surfaces of cross-linked polymer gels. The inter-colloid potential can be tuned by changing the gel stiffness or by coating the colloids with a polymer layer. On sufficiently soft substrates, the interaction induced by the polymer matrix leads to large-scale colloidal aggregation. We correlate the in-plane interaction with a colloid-surface attraction.

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Lorenzo Di Michele, Taiki Yanagishima, Anthony R. Brewer, Jurij Kotar, Seth Fraden, Erika Eiser. 2011-06-20. Interactions between colloids induced by a soft cross-linked polymer substrate. https://doi.org/10.1103/physrevlett.107.136101

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