Understanding and controlling electrophoretic motions of nanoscopic objects in fluidic channels are a central challenge in developing nanopore technology for molecular analyses. Although progress has been made in slowing the translocation velocity to meet the requirement for electrical detections of analytes via picoampere current measurements, there exists no method useful for regulating parti...

Recently, there has been a growing interest in using induced electro-osmosis to pump fluids in microfluidic devices. We show that induced electroosmosis can also be used to promote stirring and chaotic advection. To this end, we study theoretically a stirrer in which the flow patterns are alternated in time. We first analyze an idealized embodiment of the stirrer that admits a simple analytical...

In this work, we explore two methods to simultaneously measure the electroosmotic mobility in microchannels and the electrophoretic mobility of micron-sized tracer particles. The first method is based on imposing a pulsed electric field, which allows to isolate electrophoresis and electroosmosis at the startup and shutdown of the pulse, respectively. In the second method, a sinusoidal electric ...

We propose a method to separate photosystem I crystals based on size using a combination of dielectrophoresis (DEP) and electrokinesis (EK) within a microfluidic device. In this work, a model system utilizing polystyrene beads of two sizes is employed to observe the effects of DEP and EK on particles as they pass through a microsorter via electroosmosis. Particle counting and fluorescence inten...

Objective: Cerebral edema characterized as an abnormal accumulation of interstitial fluid has not been treated effectively. We propose a novel treatment approach to drive edematous out the brain by direct current utilizing tissue's electroosmotic property. Methods: A finite element (FE) head model is developed and employed assess feasibility approach. First, capacity for electric field predicti...

Chronic epidermal wounds that do not heal within 30 days afflict nearly 8.2 million patients across the country, costing US healthcare system up to $96 billion annually. Electrical stimulation (ES) of skin speeds healing chronic despite absence specific mechanisms. We are testing hypotheses understand mechanisms by which non-excitable cells involved with wound sense these EFs. For comparison, h...

BACKGROUND AND PURPOSE This study was designed to evaluate the effects of competing ions and electroosmosis on the transdermal iontophoresis of dexamethasone phosphate (Dex-Phos) and to identify the optimal conditions for its delivery. METHODS The experiments were performed using pig skin, in side-by-side diffusion cells (0.78 cm(2)), passing a constant current of 0.3 mA via Ag-AgCl electrode...