Publications by Urban Seger | EPFL Graph Search

Characterization and optimization of liquid electrodes for lateral dielectrophoresis

Philippe Renaud, Thomas Michael Braschler, Harald Van Lintel, Nicolas Demierre, Urban Seger, Olof Pontus Linderholm

Using the concept of insulator-based "electrodeless" dielectrophoresis, we present a novel geometry for shaping electric fields to achieve lateral deviation of particles in liquid flows. The field is generated by lateral planar metal electrodes and is guid ...

2007

Apparatus for manipulating, modifying and characterizing particles in a micro channel

Philippe Renaud, Thomas Michael Braschler, Nicolas Demierre, Urban Seger, Olof Pontus Linderholm

Microfluidic system comprising a space (0207) for containing a liquid and at least one lateral chamber (0201) in communication with said space, said lateral chamber containing a metal electrode (0204). The lateral chamber and the space are designed to be f ...

2007

Creating structures at the scale of cells on the fly: gentle single cell entrapment on chip

Philippe Renaud, Thomas Michael Braschler, Nicolas Demierre, Urban Seger, Olof Pontus Linderholm

2007

Analytical expression for electric filed between two facing strip electrodes in microchannels

Philippe Renaud, Urban Seger, Olof Pontus Linderholm

An analytical solution is presented for the electric field between two facing strip electrodes situated in a microchannel, as frequently used in impedance cytometry applications. The measured change in resistance as induced by a 5 mm bead moving through th ...

2006

Electrical cell manipulation in microfluidic systems

Urban Seger

This dissertation reports on the development of devices and concepts for electrical and microfluidic cell manipulation. In the present context, the term cell manipulation stands for both cell handling and cell modification. The combination of microfluidic ...

EPFL2006

Temperature measurements in microfluidic systems: Heat dissipation of negative dielectrophoresis barriers

Philippe Renaud, Martin Jordan, Urban Seger, Silvan Schnydrig

The manipulation of living biological cells in microfluidic channels by a combination of negative dielectrophoretic barriers and pressure-driven flows is widely employed in lab-on-a-chip systems. However, electric fields in conducting media induce Joule he ...

2005

Cell immersion and cell dipping in microfluidic devices

Philippe Renaud, Arnaud Bertsch, Shady Didier Gawad, Urban Seger

Combining deflective dielectrophoretic barriers with controlled pressure driven liquid flows in microfluidic devices allows accurate handling of particles such as biological cells in suspensions. Working towards cell-based lab-on-a-chip applications, a pla ...

2004

Dielectric spectroscopy in a micromachined flow cytometer: theoretical and practical considerations

Philippe Renaud, Arnaud Bertsch, Shady Didier Gawad, Urban Seger, Karen Cheung

We propose a model to determine the influence of different cell properties, such as size, membrane capacitance and cytoplasm conductivity, on the impedance spectrum as measured in a microfabricated cytometer. A dielectric sphere of equivalent complex permi ...

2004