Perspectives on digital microfluidics

Digital microfluidics (DMF) is a technique for manipulation of discrete droplets on a substrate, which allows timed motion of fluids, with accurate control, representing an alternative to steer away from the conventional paradigm of transporting fluids in enclosed channels. This review addresses the techniques for droplet control, starting with the most common, involving forces of electric origin, followed by other methods currently utilized. A discussion of the basic geometries employed, often utilizing AC voltages, is followed by a section discussing current alternatives to reduce the interaction between droplet and surfaces, frequently associated with device failure. Subsequent sections address the interfacing of DMF with other techniques, and current applications, which include topics like immunoassays, nucleic acids, proteins, cells, and studies of multicellular organisms. In addition, the integration with electromechanical systems and semiconductor structures, with still a modest number of applications, can potentially impact the development of new technologies. (C) 2016 Elsevier B.V. All rights reserved.