On the use of correction factors for the mathematical modeling of insulator based dielectrophoretic devices

Abstract

Mathematical modeling is a fundamental component in the development of new microfluidics techniques and devices. Modeling allows for the rapid testing of new system configurations while saving resources. Microscale electrokinetic (EK) techniques have significantly benefited by the advances in modeling programs and software packages. However, EK phenomena are complex to model, as they dynamically affect system characteristics, including the physical properties of the particles and fluid within the system. Insulator‐based dielectrophoresis (iDEP) is an EK technique that has received important attention during the last two decades. In particular, numerous research groups that study iDEP systems employ a combination of modeling and experimentation for developing new iDEP systems. An important fraction of these research groups has adopted the practice of employing “correction factors” to account for EK phenomena that cannot be accurately predicted in their models due to model complexity and limitations in computing resources. The present review article aims to provide the reader with an overview of the most common approaches in the use of correction factors for the modeling of iDEP systems.

Passive Dielectrophoretic Focusing of Particles and Cells in Ratchet Microchannels

“…It is because the particle's disturbances to the electric field (and as well the flow field) were neglected in the model. Such a treatment has been proved effective in our earlier studies as well as in those from other research groups [55]. To calculate the Clausius-Mosotti factor, f CM , in Equation 3, we assumed that the electric conductivity of polystyrene particles is determined solely by the surface conduction, σ s = 1 nS, through σ p = 4σ s /d [56].…”

Fine-Tuning Electrokinetic Injections Considering Nonlinear Electrokinetic Effects in Insulator-Based Devices

“…Only a handful of reports in the field of microscale EK separations have considered the effects of EP (3) in detail: five recent developments by our group [7,8,23,25,36] and the recent work of Rouhi et al [37] and Tottori et al [33]. Until recently, correction factors [38] were commonly added to mathematical models to improve the accuracy of modeling predictions. Considering the effects of EP (3) , which are enhanced at the constriction regions between posts due to the higher local electric field magnitude, allows for the first proper design of EK injection schemes by employing mathematical modeling.…”

Protein Dielectrophoresis: A Tale of Two Clausius-Mossottis—Or Something Else?

“…This is an aspect of protein DEP within the mesoscale between [CM] macroscopic and [CM] molecular , where κ or N dip , respectively, may or may not equal unity in either Equation ( 21) or (50), respectively. As reviewed by Hill and Lapizco-Encinas [104], significant efforts have been made to mathematically model iDEP-based microfluidic devices and to identify empirical correction factors that can be added to align model predictions with experimental observations. These correction factors are intended to take account of electrothermally induced fluid flow, Joule heating, particle-particle interactions and temperature gradients, for example.…”

“…These correction factors are intended to take account of electrothermally induced fluid flow, Joule heating, particle-particle interactions and temperature gradients, for example. For micronsized particles (e.g., bacteria, blood cells, polystyrene beads and yeast cells) most correction factors are found to be small (0.3 to ~15), whilst particles of diameter ~1 µm attract larger correction factors-in some cases as large as 500~600, depending on the geometry and layout of the insulating posts, hurdles or restrictions [104].…”