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arXiv · 1509.06330

Dynamic self-assembly of microscale rotors and swimmers

Megan S. Davies Wykes·Jeremie Palacci·Takuji Adachi·Leif Ristroph·Xiao Zhong·Michael D. Ward·Jun Zhang·Michael J. Shelley
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Abstract

Biological systems often involve the self-assembly of basic components into complex and function- ing structures. Artificial systems that mimic such processes can provide a well-controlled setting to explore the principles involved and also synthesize useful micromachines. Our experiments show that immotile, but active, components self-assemble into two types of structure that exhibit the fundamental forms of motility: translation and rotation. Specifically, micron-scale metallic rods are designed to induce extensile surface flows in the presence of a chemical fuel; these rods interact with each other and pair up to form either a swimmer or a rotor. Such pairs can transition reversibly be- tween these two configurations, leading to kinetics reminiscent of bacterial run-and-tumble motion.

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Megan S. Davies Wykes, Jeremie Palacci, Takuji Adachi, Leif Ristroph, Xiao Zhong, Michael D. Ward, Jun Zhang, Michael J. Shelley. 2015-09-21. Dynamic self-assembly of microscale rotors and swimmers. https://doi.org/10.1039/c5sm03127c

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