UC San Diego

The primary objective of this dissertation is to develop improve and expand the foundational electrokinetic technology available to the medical field. Dielectrophoresis (DEP), the movement of polarizable particles in an electric field gradient, is a unique and compelling method for manipulating biologic samples under both high and low conductance conditions. Effective for particles ranging from nanoparticulate matter to cell clusters and complex biological samples from whole blood and cerebrospinal fluid to urine and tears. Where research has developed many new applications, one major limitation has been discovery and particle selectivity. While the phenomenon makes many, previously improbable interactions possible, the lack of control for fine differentiation between minor particle differences makes selective isolation and discovery difficult. The problems manifest themselves during damaging down-steam purification and target isolation processing. Strict attention to device architecture and electronic signal parameters offer greater degrees of control, but confounding and inevitable conditions like joule heating and electrothermal flow can make material of interest more difficult to protect. However, careful design and control of sample conductivities, wash buffer chemistries and collection protocols make explorative efforts a reality. This clarified potential may offer confidence to future researchers to apply the DEP phenomena to discovery-based explorative research efforts.