Volume 84, Number 4, November 2008
Article Number 48001
Number of page(s) 6
Section Interdisciplinary Physics and Related Areas of Science and Technology
Published online 10 November 2008
EPL, 84 (2008) 48001
DOI: 10.1209/0295-5075/84/48001

The effect of curvature and topology on membrane hydrodynamics

M. L. Henle1, R. McGorty2, 3, A. B. Schofield4, A. D. Dinsmore2 and A. J. Levine1, 5

1   Department of Chemistry and Biochemistry, University of California - Los Angeles, CA 90095, USA
2   Department of Physics, University of Massachusetts - Amherst, MA 01003, USA
3   Department of Physics, Harvard University - Cambridge, MA 02138, USA
4   School of Physics, The University of Edinburgh - Edinburgh EH9 3JZ, UK, EU
5   California Nanosystems Institute, University of California - Los Angeles, CA 90095, USA

received 11 July 2008; accepted in final form 5 October 2008; published November 2008
published online 10 November 2008

We study the mobilities of point-like and extended objects (rods) on a spherical membrane to show how these quantities are modified in a striking manner by the curvature and topology of the membrane. We also present theoretical calculations and experimental measurements of the membrane fluid velocity field around a moving rod bound to the crowded interface of a water-in-oil droplet. By using different droplet sizes, membrane viscosities, and rod lengths, we show that the viscosity mismatch between the interior and exterior fluids leads to a suppression of the fluid flow on small droplets that cannot be captured by the flat-membrane predictions.

87.16.dp - Transport, including channels, pores, and lateral diffusion.
47.63.-b - Biological fluid dynamics.
68.05.-n - Liquid-liquid interfaces.

© EPLA 2008