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arXiv · 1710.02346

Particle transport across a channel via an oscillating potential

Yizhou Tan·Leonardo Dagdug·Jannes Gladrow·Ulrich F. Keyser·Stefano Pagliara
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Abstract

Membrane protein transporters alternate their substrate-binding sites between the extracellular and cytosolic side of the membrane according to the alternating access mechanism. Inspired by this intriguing mechanism devised by nature, we study particle transport through a channel coupled with an energy well that oscillates its position between the two entrances of the channel. We optimize particle transport across the channel by adjusting the oscillation frequency. At the optimal oscillation frequency, the translocation rate through the channel is a hundred times higher with respect to free diffusion across the channel. Our findings reveal the effect of time dependent potentials on particle transport across a channel and will be relevant for membrane transport and microfluidics application.

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Yizhou Tan, Leonardo Dagdug, Jannes Gladrow, Ulrich F. Keyser, Stefano Pagliara. 2017-10-06. Particle transport across a channel via an oscillating potential. https://doi.org/10.1103/physreve.96.052401

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