square logo


navigation:  << previous  ||  next >>

Electric Tweezers: Positive Dielectrophoresis Based Positioning and Orientation of Nano- and Micro- Sized Particles


Brian Edwards, Nader Engheta

Our goal is the planer positioning and orientation of individual micro- and nanometer sized objects which is simultaneously touchless and applicable to many materials. We have developed a general system using positive dielectrophoretic forces. In this method, the particle responds to carefully controlled voltages on an array of electrodes. These voltages can be mathematically linked to a desired force and orientation for each nanoparticle. We use this technique to manipulate a 6 micron long 300nm diameter gold nanorod in between five electrodes spaced on a circle of 200 micron diameter. The simulation to the right demonstrates how the voltage field (in black) and the potential energy (in colored contour) can be simultaneously changed to produce force and angle on a nanorod.

img009Still frame from movie showing the manipulation of a 6 micron long gold rod
Edwards B, Engheta N, Evoy S 2005 Journal of Applied Physics 98
img009PCB Board which is in development to reduce the entire experimental apparatus to a size which fits on a microscope stage.



Nano/Bio Interface Center @ The University of Pennsylvania
Home | Participents | Research | Education | Industry | Partners | Publications | Facilities | Events | Calendar | NIRT | Members