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arXiv · 2408.11569

Specific yet transient bonds between anisotropic colloids

Muraleedharapai Mayarani·Justine Laurent·Martin Lenz·Olivia du Roure·Julien Heuvingh
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Abstract

Self-assembly of colloidal particles is a promising avenue to control the shape and dynamics of larger aggregates. However, achieving the necessary fine control over the dynamics and specificity of the bonds between such particles remains a challenge. Here we demonstrate such control in bonds mediated by depletion interactions between anisotropic colloids that we 3D-print in the shape of half disks with sub-micron resolution. When brought together by diffusion, the particles interact in different configurations but the interaction through the flat faces is by far the longest-lasting. All bonds are flexible and transient, and we demonstrate control over their life time through the depletant concentration in quantitative agreement with a simple physical model. This basic design could be extended to manufacture particles with multiple binding sites to engineer directional assembly with multiple particles.

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Muraleedharapai Mayarani, Justine Laurent, Martin Lenz, Olivia du Roure, Julien Heuvingh. 2024-08-21. Specific yet transient bonds between anisotropic colloids. https://arxiv.org/abs/2408.11569

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