Microfluidic-Chip Technology for Disease Diagnostic Applications via Dielectrophoresis

Dielectrophoresis (DEP), an electrokinetic tool utilized to sort, trap, enrich, and characterize particles based on the particles’ dielectric properties, has seen significant growth during the past two decades. The particles of interest range from sub-micron or nanoparticles like exosomes and proteins to micron-sized particles like stem cells and cancer cells. Dielectrophoresis is a powerful technique that offers unique capabilities and scientific solutions in a label-free way that cannot be addressed using conventional methods. This chapter discusses about the different forces influencing dielectrophoretic sorting or trapping, i.e. electrophoresis and electro-osmosis; particle characterization techniques including electrorotation and DEP crossover frequency measurement methods; modeling of dielectric properties based on the shape and layers of the particle; sorting device platform modeling via commercial software packages; and applications of dielectrophoresis for disease diagnostics particularly DNA, virus, bacteria, yeasts, and blood cells.