Insulator Based Dielectrophoresis: Micro, Nano, and Molecular Scale Biological Applications

Abstract

Insulator based dielectrophoresis (iDEP) is becoming increasingly important in emerging biomolecular applications, including particle purification, fractionation, and separation. Compared to conventional electrode-based dielectrophoresis (eDEP) techniques, iDEP has been demonstrated to have a higher degree of selectivity of biological samples while also being less biologically intrusive. Over the past two decades, substantial technological advances have been made, enabling iDEP to be applied from micro, to nano and molecular scales. Soft particles, including cell organelles, viruses, proteins, and nucleic acids, have been manipulated using iDEP, enabling the exploration of subnanometer biological interactions. Recent investigations using this technique have demonstrated a wide range of applications, including biomarker screening, protein folding analysis, and molecular sensing. Here, we review current state-of-art research on iDEP systems and highlight potential future work.

Deep-Learning Based Estimation of Dielectrophoretic Force

“…Electric field-induced dipole formation causes pearl chaining of particles that are aligned along an electric field [4,5]. Pearl chains are direct indicators of DEP forces and can be correlated to dielectric variations of a variety of microparticles, including biological cells [1][2][3]6,7].…”

A review: Dielectrophoresis for characterizing and separating similar cell subpopulations based on bioelectric property changes due to disease progression and therapy assessment

“…It is important to note that recently it was discovered that the induced motion of a particle by iDEP generated from a DC signal (DC-iDEP) is predominantly a result of second-order electrophoresis on the particle, rather than dielectrophoresis [23,24]. Various recent applications of iDEP have been highlighted in other works [25,26]. eROT is a single-cell analysis technique that employs quadrupole electrodes energized by four out-of-phase sinusoidal signals that cause the cell of interest to rotate (Figure 1B).…”

Dynamically controlled dielectrophoresis using resonant tuning

“…Thus the additional handles provided by the resonant circuit enable us to tune the overall spatial profile of the dielectrophoretic traps to achieve the dual objectives of extending the trap range and minimizing the electric field that the trapped sample is exposed to at the stable equilibrium position without redesigning the trap electrodes. This is especially useful for the study of trapped biological specimen without causing high field induced sample damage [64][65][66].…”

“…In such systems, if the supply voltage is increased to exert a larger dielectrophoretic force to trap particles located further away from the electrode, the electric-field strength that the trapped sample will be exposed to at the equilibrium trapping position on the electrode will also increase proportionally (larger voltage across the electrodes would lead to larger electric field). This may lead to unwanted high field induced effects (especially true for biochemical reagents and biological samples like cells) [64][65][66]. Hence, additional degrees of freedom are required to go beyond uniform spatial scaling of dielectrophoretic forces and exert a larger dielectrophoretic force on particles located further away from the electrode while exposing them to reduced electric-field intensities at the stable trapping position.…”