We present a numerical study of induced-charge electro-osmosis (ICEO) of electrolytes in microfluidic channels containing a fixed dielectric structure. ICEO is the nonlinear electro-osmotic slip that occurs in the electrolyte when an applied electric field acts on the ionic charge it induces around the polarizable surface of the dielectric structure. We also establish a method for optimizing th...

Electrically controlled dynamics of fluids and particles at microscales is a fascinating area of research with applications ranging from microfluidics and sensing to sorting of biomolecules. The driving mechanisms are electric forces acting on spatially separated charges in an isotropic medium such as water. Here, we demonstrate that anisotropic conductivity of liquid crystals enables new mecha...

We recently introduced methods to tether phospholipid vesicles or proteoliposomes onto a fluid-supported lipid bilayer using DNA hybridization (Yoshina-Ishii, C.; Miller, G. P.; Kraft, M. L.; Kool, E. T.; Boxer, S. G. J. Am. Chem. Soc. 2005, 127, 1356-1357). These intact tethered vesicles diffuse in two dimensions parallel to the supporting membrane surface. In this article, we report the dynam...

We analyze the general phenomenon of induced-charge electro-osmosis (ICEO), nonlinear electroosmotic slip generated when an electric field acts on its own induced charge around a polarizable surface, in the context of microfluidics. Simple ICEO flows are first observed around a platinum wire in a polymer microchannel. While convenient for scaling analysis of resulting flows, this geometry prove...

We derive a mathematical model of a nematic electrolyte based on a variational formulation of nematodynamics. We verify the model by comparing its predictions to the results of the experiments on the substrate-controlled liquid-crystal-enabled electrokinetics. In the experiments, a nematic liquid crystal confined to a thin planar cell with surface-patterned anchoring conditions exhibits electro...

Overview Membranes in the outer hair cell lateral wall form a naturally occurring nanostructure which acts as a microelectromechanical (MEM) system. Computational and optical techniques are being developed to predict, verify and refine the description of nanoscale behavior in the outer hair cell (OHC) lateral wall. The biological, engineering and physics expertise of an interdisciplinary three-...

We describe the general phenomenon of ‘induced-charge electro-osmosis’ (ICEO) — the nonlinear electro-osmotic slip that occurs when an applied field acts on the ionic charge it induces around a polarizable surface. Motivated by a simple physical picture, we calculate ICEO flows around conducting cylinders in steady (DC), oscillatory (AC), and suddenly-applied electric fields. This picture, and ...