Deterministic separation of particles by electrophoresis: e-DLD

A suspension of particles of different size driven through an array of posts, by either gravity or flow, results into streams of particles moving in different directions, which can be used for the continuous separation of different species. In this work, we explore a spatially uniform electric field as a driving force. Specifically, we apply an electric field to a quiescent aqueous suspension (constant pH) of spherical particles of different size, across an isotropic two dimensional array of cylindrical posts at different angles with respect to the principal directions of the array and track the motion of particles as they move through the array. In general, the results are in agreement with the existence of deterministic lateral displacement and directional locking, as with the other driving fields. We discuss characterization and separation experiments as well as the advantages of using electric field to separate particles.