Regensburg 2019 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 58: Nanostructures, Nanostructuring and Nanosized Soft Matter

CPP 58.9: Vortrag

Donnerstag, 4. April 2019, 17:30–17:45, H13

High-resolution multi-channel nanoparticle separation utilizing rocked Brownian motors — •Christian Schwemmer, Francesca Ruggeri, Xiaoyu Ma, and Armin Knoll — IBM Research - Zurich, Switzerland

Artificial Brownian motors were inspired by how nature achieves directed transport in highly diffusive environments [1]. Their two main ingredients are an asymmetric potential and a zero-mean driving force. Our implementation employs the electrostatic interactions in weak electrolytes between charged nanoparticles and like charged surfaces of a nanofluidic slit [2] to define a ratchet shaped energy landscape [3]. A zero-mean AC electric field across the slit induces an electro-osmotically transduced driving force, resulting in drift speeds of up to 50 µm/s for 60 nm gold spheres. The motors exhibit an Arrhenius-like onset of the particle current with decreasing amplitude of the energy barriers, a promising feature for particle separation [4]. Based on this property, we developed a fast and highly selective nanoparticle sorting device to separate gold spheres of nominally 80 nm and 100 nm diameter along its y-axis into 30 subpopulations with <2 nm sorting resolution. By switching the AC field to the x-direction, the separated populations are transported to compartments for collection. Thus, scalable continuous multi-channel particle separation is within reach.
[1] Hänggi et al., Rev. Mod. Phys., 81, 387 (2009)
Krishnan et al., Nature, 467, 692 (2010)
Skaug et al., Science, 359, 1505 (2018)
Bartussek et al., Europhs. Lett., 28, 459 (1994)