Micro & Bio Fluidics, Lab-on-Chip – Page 48

Macromolecules in Microdevices: Multiscale simulation of DNA dynamics in model microfluidic geometries

Jendrejack R.M., de Pablo J.J., Graham M.D., University of Wisconsin-Madison, US

Simple arguments predict that the dynamics of a dissolved macromolecule confined to a channel comparable to its equilibrium coil size (~1 um for viral DNA) are quite different from those in free solution, because of [...]

Separation of Long Polyelectrolytes in a Microfuluidic Channel with Constrictions: A Monte Carlo Study

Tessier F., Slater G.W., University of Ottawa, CA

We present Monte Carlo simulation results for the motion of long linear polyelectrolytes inside a microchannel of molecular dimensions, structured as a periodic array of wells linked by narrow constrictions. Molecules are driven in the [...]

Modeling of Joule Heating in Electrophoretic Separation Microchips

Wang Y., Lin Q., Hoburg J.F., Mukherjee T., Carnegie Mellon University, US

This paper presents a model for Joule heating induced analyte dispersion in electrophoretic separation channels with a rectangular cross section. The model is in closed form and captures the effect of cross-sectional geometry. Three-dimensional numerical [...]

Analysis of Physico-Chemical Processes in an Amperometric Oxygen Biosensor

Krishnamoorthy S., Feng J.J., Makhijani V.B., Gao C., Choi J.W., Ahn C., CFD Research Corporation, US

Amperometric techniques are commonly used in lab-on-a-chip systems to sense various blood gas analytes such as H+, CO2, O2, etc. In the present study, a microchip-based amperometric biosensor, being developed as a part of plastic-based [...]

Simulation of Electro-Osmotically Driven Microsythesis Systems

Oosterbroek R.E., Goedbloed M., van den Berg A., University of TWente, NL

Modeling, optimization, and the realization of an electroosmotically driven chemical microsynthesis system for Wittig reactions are presented. Essential for good functioning of the chemical liquid reaction system is controllability of the supplied chemicals, independently of [...]

Electroosmotic Flow and Zone Broadening in Microfluidic Channels of Variable Cross-Section and Wall Charge

Ghosal S., Lu Z., Northwestern University, US

Electroosmotic flow is often the method of choice for generating fluid flows in micro fluidic devices. The resulting flow has a characteristic at profile which has the advantage of very low axial dispersion. This is [...]

Squeezing Flow of Particles and Large Molecules Suspended in a Liquid Through Nanochannels

Acrivos A., Khusid B., Koplik J., Drazer G., New Jersey Institute of Technology, US

The presentation addresses the status of current understanding of the hydrodynamic phenomena accompanied the motion of a nanometer-sized particle through a nanotube.

Simulation of Electrically-Excited Flows in Microchannels for Mixing Application

Meisel I., Ehrhard P., Forschungszentrum Karlsruhe GmbH, DE

In the present paper we propose a method for improved mixing in microchannels. The basic idea is to excite a secondary vortex flow around an obstacle within the micromixer by applying an external oscillatory electrical [...]

A Compact Model for Flowrate and Pressure Computation in Micro-fluidic Devices

Qiao R., Aluru N.R., University of Illinois at Urbana-Champaign, US

A compact model to compute flowrate and pressure in micro-fluidic devices is presented. The micro-fluidic flow can be driven by either an applied electric field or by a pressure gradient or both. In the proposed [...]

Simulation of Hydrodynamic Dispersion in Gas/Liquid Microreactors

Hardt S., Doffing F., Pennemann H., Institut für Mikrotechnik Mainz GmbH, DE

Dispersion and spreading of concentration signals in gas/liquid microreactors is studied with methods of computational fluid dynamics (CFD). It is shown that conventional reactor designs exhibit a broad residence-time distribution due to convective signal dispersion. [...]