Abstract: Embodiments of the present invention comprise a surface microfluidic system with varying coplanar electrode structure capable of precision dispensing of an array of variable volume droplets in a rapid, controlled and automated fashion. Furthermore, the invention provides surface microfluidic methods and systems for the creation and transport of emulsion droplets, including vesicles and cells.

Abstract: The invention integrates a two-stage dielectrophoretic (DEP) droplet dispensing and distribution system with particulate DEP to create a novel LOC platform capable of manipulating biological cells based on the varied dielectrophoretic signatures that distinguish cells in a population, for example, healthy from diseased cells. The two-stage DEP droplet transport system acts as the backbone of this application, providing the essential dispensing and distribution function, while particulate DEP provides the critical capability to characterize and analyze the heterogeneous biological cell populations routinely encountered in biotechnology and clinical settings.

Abstract: A filter has a conduit having an opening for flow of fluid into the conduit, a pump for pumping fluid into the conduit through the opening, electrodes spaced apart from each other across the opening such that fluid flowing through the opening passes between the electrodes; and an AC electrical source for the electrodes, the source of AC electrical energy having a frequency and voltage such that an electric field created by the AC electrical energy in the area around the electrodes imposes a negative dielectrophoretic force on target particles carried by the fluid, the negative dielectrophoretic force being opposed to the direction of fluid flow through the opening and having sufficient strength to prevent the target particles from passing between the electrodes into the conduit. The filter is mounted in a bioreactor for filtering viable cells and retaining them in culture medium.