Nozzle-Shaped Electrode Configuration for Dielectrophoretic 3D-Focusing of Microparticles.

Krishna Krishna,Mathew Mathew,Alnaimat Alnaimat

doi:10.3390/mi10090585

Krishna Krishna, Mathew Mathew + Show 1 more

Open Access

https://doi.org/10.3390/mi10090585

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Journal: Micromachines	Publication Date: Aug 31, 2019
Citations: 4	License type: CC BY 4.0

Affiliation: United Arab Emirates University

Abstract

An experimentally validated mathematical model of a microfluidic device with nozzle-shaped electrode configuration for realizing dielectrophoresis based 3D-focusing is presented in the article. Two right-triangle shaped electrodes on the top and bottom surfaces make up the nozzle-shaped electrode configuration. The mathematical model consists of equations describing the motion of microparticles as well as profiles of electric potential, electric field, and fluid flow inside the microchannel. The influence of forces associated with inertia, gravity, drag, virtual mass, dielectrophoresis, and buoyancy are taken into account in the model. The performance of the microfluidic device is quantified in terms of horizontal and vertical focusing parameters. The influence of operating parameters, such as applied electric potential and volumetric flow rate, as well as geometric parameters, such as electrode dimensions and microchannel dimensions, are analyzed using the model. The performance of the microfluidic device enhances with an increase in applied electric potential and reduction in volumetric flow rate. Additionally, the performance of the microfluidic device improves with reduction in microchannel height and increase in microparticle radius while degrading with increase in reduction in electrode length and width. The model is of great benefit as it allows for generating working designs of the proposed microfluidic device with the desired performance metrics.

Highlights

Microfluidic devices employ channels with hydraulic diameters smaller than 1 mm and this brings about certain advantages such as low sample and reagent requirement, small footprint, portability, and low power consumption [1,2]
The mathematical model is used for parametric study to understand the influence of operating/geometric parameters on the 3D-focusing efficiency of the device
The performance of the microfluidic device is quantified in terms of horizontal and vertical focusing parameters which are mathematically equivalent to the standard deviation of the horizontal and vertical positions of the microparticle evaluated at the exit section on the microfluidic device

Summary

Introduction

Microfluidic devices employ channels with hydraulic diameters smaller than 1 mm and this brings about certain advantages such as low sample and reagent requirement, small footprint, portability, and low power consumption [1,2]. Any microparticle subjected to nDEP using the electrode configuration shown in Figure 2 will b(be) pushed towards the center of the microchannel thereby achieving 3D-focusing of microparticles; the electrode configuration functions like a nozzle with regFaFiriggduurtroee1t1h. Any microparticle subjected to nDEP using the electrode configuration shown in Figure 2 will be pushed towards the center of the microchannel thereby achieving 3D-focusing of microparticles; the electrode configuration functions like a nozzle with regard to t(ah)e movement of microparticles. Knowledge of the axial distance required for reaching steady state dictates the actual size of the microfluidic device

Theoretical Model

Model Validation

Conclusions