Enhanced electrokinetic manipulation and impedance sensing using FPGA digital signal processing
Electrokinetic manipulation of microscopic biological particles, such as bacteria and other cells, is useful in the technology of lab-on-a-chip devices and micro-total-analysis systems (唁S). In electrokinetic manipulation, non-uniform electric fields are used to exploit the dielectric properties of suspended biological microparticles, to induce forces and torques on the particles. The electric fields are produced by planar electrode arrays patterned on electrically-insulating substrates. Biological microparticles are dielectrically-heterogeneous structures. Each different type of biological cell has a distinct dielectric frequency response signature. This dielectric distinction allows specificity when manipulating biological microparticles using electrokinetics. Electrokinetic microbiological particle manipulation has numerous potential applications in biotechnology, such as the separation and study of cancerous cells, determining the viability of cells, as well as enabling more automation and parallelization in microbiological research and pathology. This paper presents microfabricated devices for the manipulation of biological microparticles using electrokinetics. Methods of impedance sensing for determining microparticle concentration and type are also discussed. This paper also presents methods of using digital signal processing systems to enhance the manipulation and sensing of the microbiological particles. A Field-Programmable Gate Array (FPGA) based system is demonstrated which is used to digitally synthesize signals for electrokinetic actuation, and to process signals for impedance sensing.
BioMEMS and Nanotechnology II, Proc. SPIE, Vol. 6036