Controlled surface-induced flows from the motion of self-assembled colloidal walkers

Proc Natl Acad Sci U S A. 2010 Jan 12;107(2):535-40. doi: 10.1073/pnas.0906489107. Epub 2009 Dec 18.


Biological flows at the microscopic scale are important for the transport of nutrients, locomotion, and differentiation. Here, we present a unique approach for creating controlled, surface-induced flows inspired by a ubiquitous biological system, cilia. Our design is based on a collection of self-assembled colloidal rotors that "walk" along surfaces in the presence of a rotating magnetic field. These rotors are held together solely by magnetic forces that allow for reversible assembly and disassembly of the chains. Furthermore, rotation of the magnetic field allows for straightforward manipulation of the shape and motion of these chains. This system offers a simple and versatile approach for designing microfluidic devices as well as for studying fundamental questions in cooperative-driven motion and transport at the microscopic level.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Transport / physiology
  • Biology / methods*
  • Cilia / physiology*
  • Colloids*
  • Computer Simulation
  • Electromagnetic Fields
  • Kinetics
  • Magnetics
  • Mathematics
  • Motion
  • Pigmentation / physiology
  • Rotation


  • Colloids