Viscophoretic particle transport
Abstract
Viscosity is a fundamental property of liquids and determines the diffusivity of suspended particles. A gradient in viscosity leads to a gradient in diffusivity, yet it is unknown whether such a gradient can lead to directed transport of particles. In this work, we generate a steep, stable viscosity gradient in a microfluidic channel and image the resulting transport of suspended nanoparticles at the single-particle level using high-resolution microscopy. We observe high viscophoretic drift velocities that significantly exceed theoretical predictions. In addition, we utilize viscophoresis for a new type of particle trap. We provide a first quantification of a transport phenomenon that is of importance in any system and any application exhibiting viscosity gradients, for example in separation using membrane technology as well as in inter- and intracellular biomolecular transport.
Cite
@article{arxiv.2212.11503,
title = {Viscophoretic particle transport},
author = {Vahid Khandan and Vincent Boerkamp and Abbas Jabermoradi and Mattia Fontana and Johannes Hohlbein and Elisabeth Verpoorte and Ryan C. Chiechi and Klaus Mathwig},
journal= {arXiv preprint arXiv:2212.11503},
year = {2025}
}