Sedimentation isotropic particles

Positive DEP drives particles towards field maxima and negative DEP moves them to field minima. It is only possible to create field maxima at the surfaces of the electrodes, no maximum can exist elsewhere in an isotropic solution. Trapping or positioning of particles by positive DEP therefore requires the dielectrophoretic force to be balanced by some other force (e.g. sedimentation, buoyancy or flow) and to be subjected to feedback control. This was first done with a two electrode system by Jones and Kaler [33-37]. 

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