US – Page 443 – TechConnect Briefs

Biochemical Binding in Microspheres-Based-Imunoassays

Prabhakarpandian B., Shah K.B., Sundaram S., Makhijani V.B., CFD Research Corporation, US

Microspheres (referred commonly as beads) are being extensively used in biochemical assays as supports for proteins, DNA, etc. We have successfully developed computational models for simulating sample detection using flowing beads. The model fully integrates [...]

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 [...]

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 [...]

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.

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 [...]

System Performance Evaluation with SystemC for Two PCR Microelectrofluidic Systems

Zhang T., Chakrabarty K., Fair R.B., Cadence Design Systems, Inc., US

We present a performance comparison between two types of microfluidic systems - continuous-flow systems and droplet-based systems. The comparison based on a specific microfluidic application - a polymerase chain reaction (PCR) system. The modeling and [...]

Novel Microfluidic Jet Deflection: Significant Modeling Challenge with Great Application Potential

Delametter C.N., Trauernicht D.P., Chwalek J.M., Eastman Kodak Company, US

A novel method is described for deflecting a liquid jet emanating from an orifice having a diameter of approximately ten microns. While awkward mechanical valves or unwieldy electrodes can be used to deflect a jet, [...]

Direct Numerical Simulation of Moving Charged, Flexible Bodies with Thermal Fluctuations

Patankar N.A., Northwestern University, US

The interaction of sub-micron scale objects with fluids is an important problem encountered in miniaturized systems. Various physical phenomena should be modeled simultaneously for a fundamental investigation of these systems. Our objective is to develop [...]