Abstract for the APS Division of Fluid Dynamics Meeting San Diego, CA, November 18-20, 2001 Electophoresis of Conductors: Theory and Microfluidic Applications ------------------------------------------------------------------ Martin Z. Bazant (Department of Mathematics, MIT) and Todd Squires (Department of Physics, Harvard University) When a background electric field is applied to a conductor immersed in a liquid electrolyte, its surface charge evolves to produce a nonuniform zeta potential, and the resulting electro-osmotic flow is very different from the familiar case of an insulator (with a fixed zeta potential). As the electric field increases, it is predicted that a charged, conducting sphere reaches a limiting electrophoretic velocity (i.e. the mobility vanishes), and a secondary flow develops, which sucks in fluid along the field axis and ejects it radially. In this talk, a simple physical picture of such intriguing phenomena will be presented, and a variety of microfluidic applications will be discussed, such as micro-pumps and mixers driven by AC electric fields.