3D Concentric Electrodes-Based Alternating Current Electrohydrodynamics: Design, Simulation, Fabrication, and Potential Applications for Bioassays

Abstract

Two-dimensional concentric asymmetric microelectrodes play a crucial role in developing sensitive and specific biological assays using fluid micromixing generated by alternating current electrohydrodynamics (ac-EHD). This paper reports the design, simulation, fabrication, and characterization of fluid motion generated by 3D concentric microelectrodes for the first time. Electric field simulations are used to compare electric field distribution at the electrodes and to analyze its effects on microfluidic micromixing in 2D and 3D electrodes. Three-dimensional devices show higher electric field peak values, resulting in better fluid micromixing than 2D devices. As a proof of concept, we design a simple biological assay comprising specific attachment of streptavidin beads onto the biotin-modified electrodes (2D and 3D), which shows ~40% higher efficiency of capturing specific beads in the case of 3D ac-EHD device compared to the 2D device. Our results show a significant contribution toward developing 3D ac-EHD devices that can be used to create more efficient biological assays in the future.

Numerical prediction of transient electrohydrodynamic instabilities under an alternating current electric field and unipolar injection

“…The Coulomb force acts on charges and causes the fluid to flow. Owing to its low noise and energy consumption and lack of mechanical movement, EHD technology has unique advantages in active flow control [ 1 ], microchannel transport [ 2 ], heat transfer enhancement [ 3 ], EHD drag pumps [ 4 , 5 ], alternating current (AC)–EHD fluid micromixing and microfluidic systems [ 6 , 7 , 8 ], EHD printing driven by pulsed and AC voltages [ 9 , 10 , 11 ], atomization technology [ 12 ], and so on.…”

Numerical Prediction of Transient Electrohydrodynamic Instabilities Under an Alternating Current Electric Field and Unipolar Injection

“…The Coulomb force from the electric field that was exerted on the space charges injected from the electrodes induced the flow motion. Owing to its low noise and energy consumption and lack of mechanical movement, the EHD has unique advantages in active flow control, 2 microchannels transport, 3 heat transfer enhancement, 4 EHD drag pumps, 5,6 alternating current (AC)-EHD fluid micromixing and microfluidic systems, [7][8][9] EHD printing driven by pulsed and AC voltages, [10][11][12] atomization technology, 13 and so on.…”