A Microfluidic System for Biological Particle Enrichment Using Contactless Dielectrophoresis

A microfluidic system for the enrichment of biological particles, operating on the principle of dielectrophoresis (DEP), is presented. Through the use of a unique manifestation of DEP, contactless DEP (cDEP), this system illustrates the potential to sidestep the common trade-off between sample throughput and selectivity without the need of a complicated fabrication process. The ability to concentrate particles from a sample fluid is validated experimentally through the concentration of 2-mu m polystyrene beads and live THP-I human leukemia cells from a heterogeneous media solution. Finite element analysis of the electric field within the microfluidic channel of the device allows for the determination of effective experimental parameters and accurate predictions of a particle's trajectory through the device. The concentration of particles combined with a fabrication procedure conducive to mass production makes cDEP an attractive alternative to current sample enrichment technologies. (JALA 2010;15:224-32)