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arXiv · 1708.02228

Mobile Microelectrodes: Towards active spatio-temporal control of the electric field and selective cargo assembly

Alicia M Boymelgreen·Tov Balli·Touvia Miloh·Gilad Yossifon
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Abstract

With an eye towards next-generation, smart, micro/nanofluidic devices, capable of responding to external stimuli or changes in environment, we demonstrate a means to achieve dynamic control of the spatio-temporal properties of the electric field in a standardized microfluidic chamber. Typical top-down patterning, currently used to design the field distribution, is replaced by freely-suspended colloids which locally disturb the electric field from the bottom-up. Even under uniform forcing, polarization of the colloid induces the formation of strong, three-dimensional gradients at its surface - essentially repurposing it into a portable floating electrode whose precise location can be manipulated to reconfigure the electric field in real time. Focusing on active Janus colloids as a sample platform, we measure the strength of the induced gradients and highlight the advantages of a colloid-based system by revealing a prototype for an all-in-one cargo carrier, capable of on-demand, selective, label-free assembly and transport of micro/nano sized targets.

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Alicia M Boymelgreen, Tov Balli, Touvia Miloh, Gilad Yossifon. 2017-08-07. Mobile Microelectrodes: Towards active spatio-temporal control of the electric field and selective cargo assembly. https://arxiv.org/abs/1708.02228

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