(441d) The Integration of Dielectrophoresis On a CD-Like Microfluidics Platform

We present the integration of a novel Dielectrophoresis (DEP)-assisted filter on a compact disc (CD)-like centrifugal platform: a SpinDEP platform. By placing the DEP chip on a rotating disk, we reduce the footprint of the typical DEP system by eliminating bulky precision pumps and fluidic interconnects. The dielectrophoresis filter is implemented using Carbon-electrode Dielectrophoresis (CarbonDEP) which refers to the use of carbon surfaces as electrodes to induce DEP. In this case 3D electrodes penetrating the bulk of the sample are used. Compared to traditional DEP devices that employ planar metal electrodes, the 3D carbon electrode structure allows for superior filter throughput. To demonstrate the system setup as an efficient filtering mechanism we separated latex particles from a mix of latex and yeast cells at flow rates up to 40 ul/min. The demonstrated platform simplifies the use of DEP for filtering applications. In contrast to peristaltic or syringe pumps, centrifugal pumping offers several advantages. 1) Reduction of system footprint. SpinDEP platform is the size of a traditional data CD. Even when employed function generator in this work was of traditional dimensions, a sinusoidal signal generator could easily be miniaturized to be integrated in the SpinDEP platform. 2) Elimination of fluidic interconnects such as tubing, sample loading docks/ports, valves, splitters and/or syringe connectors. 3) SpinDEP is a self-contained platform. The fluidic network is contained within the chip thus minimizing the possibility of leaks in the system. 4) Programmable pumping forces can be implemented by different spinning protocols with variations in time, angular velocity and acceleration. 5) The cost of a DEP platform is greatly reduced by the elimination of an expensive precision pump and a variety of fluidic interconnects. 6) Modular setup with the ability to be integrated with sample preparation and detection architectures. Based on our previous experience with syringe pumps, we can say that the time to run a given DEP experiment is also greatly reduced. Furthermore, CD micro fluidics intrinsically eliminates air bubbles from the system before sample gets flowed over the DEP filter. The ultimate goal is to obtain a sample-to-result system for diagnostics and clinical applications.