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. This journal is © The Royal Society of Chemistry 2012