High sensitivity three-dimensional insulator-based dielectrophoresis

Insulator-based dielectrophoresis (iDEP) is a very promising technique for sorting microparticles based on their electrical properties. The need for microfabricated electrode arrays is eliminated by using constrictions in a microchannel to induce large electric field gradients. In this work, micro-milling is used to build devices with three-dimensional features that exhibit very large constriction ratios. These three-dimensional insulator-based dielectrophoresis (3DiDEP) devices allow for trapping microparticles at average electric fields one order of magnitude lower than two-dimensional designs with the same footprint. Low voltage operation minimizes Joule heating effects that have limited previous systems, opening up the possibility for new biological applications of iDEP.