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arXiv · 1708.09489

Thermal Molecular Focusing: Tunable Cross Effect of Phoresis and Advection

Tatsuya Fukuyama·Sho Nakama·Yusuke T. Maeda
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Abstract

The control of solute fluxes through either microscopic phoresis or hydrodynamic advection is a fundamental way to transport molecules, which are ubiquitously present in nature and technology. We study the transport of large solute such as DNA driven by a time-dependent thermal field in a polymer solution. Heat propagation of a single heat spot moving back and forth gives rise to the molecular focusing of DNA with frequency-tunable control. We developed a theoretical model, where heat conduction, viscoelastic expansion of walls, and the viscosity gradient of a smaller solute are coupled, and that can explain the underlying hydrodynamic focusing and its interplay with phoretic transports. This cross effect may allow one to design a unique miniaturized pump in microfluidics.

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Tatsuya Fukuyama, Sho Nakama, Yusuke T. Maeda. 2017-08-30. Thermal Molecular Focusing: Tunable Cross Effect of Phoresis and Advection. https://doi.org/10.1039/c8sm00754c

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