Computational Prototyping of the Programmable Fluid Processor

Jun Zeng and Tom Korsmeyer Coventor, Inc. The Programmable Fluid Processor (PFP), currently under development at M. D. Anderson Cancer Center, will have applications in disease screening, environmental monitoring, and battlefield detection of biochemical agents [1]. In this device, an electrostatic field exerts forces on dielectric droplets suspended in an immiscible insulating liquid medium. This phenomenon is known as dielectrophoresis (DEP). The electrostatic field is generated by an array of electrodes, each of which is addressable so that a droplet, or a group of droplets, can be directed to desired locations, where the droplets can merge, mix, and split. The droplets. | Computational Prototyping of the Programmable Fluid Processor Jun Zeng and Tom Korsmeyer Coventor Inc. The Programmable Fluid Processor PFP currently under development at M. D. Anderson Cancer Center will have applications in disease screening environmental monitoring and battlefield detection of biochemical agents 1 . In this device an electrostatic field exerts forces on dielectric droplets suspended in an immiscible insulating liquid medium. This phenomenon is known as dielectrophoresis DEP . The electrostatic field is generated by an array of Chamber top Figure 1 Elevation view of the Programmable Fluid Processor. electrodes each of which is addressable so that a droplet or a group of droplets can be directed to desired locations where the droplets can merge mix and split. The droplets are used as carriers of different chemical compounds so that a programmed chemical assay can be conducted. Recent advances in semiconductor manufacturing technology have enabled researchers to fabricate such BioChips at the size of less than a centimeter 2 . The design of the PFP and its operating programs calls for a detailed understanding of DEP-driven droplet formation and migration that is droplet behavior with a given electrode configuration must be reliably predicted. This demands full-dimensional transient simulation capabilities that incorporate electromechanics and multiphase-flow hydrodynamics. The work reported here addresses such a simulation need for the first time. We describe a full-dimensional transient electrohydrodynamics numerical simulation tool based on a proven computational fluid dynamics technique 3 . We present the results of this simulation tool from an investigation of droplet dielectrophoresis in the context of the PFP. These include a study of droplet migration under a non-uniform electric field and a study of the effects on droplet behavior of droplet dimension electrode dimension electrode spacing and dielectric coating. Figure 2 Three electrostatic