Microfluidic Separation of Blood Cells Based on the Negative Dielectrophoresis Operated by Three Dimensional Microband Electrodes

Abstract

A microfluidic device is presented for the continuous separation of red blood cells (RBCs) and white blood cells (WBCs) in a label-free manner based on negative dielectrophoresis (n-DEP). An alteration of the electric field, generated by pairs of slanted electrodes (separators) that is fabricated by covering parts of single slanted electrodes with an insulating layer is used to separate cells by their sizes. The repulsive force of n-DEP formed by slanted electrodes prepared on both the top and bottom substrates led to the deflection of the cell flow in lateral directions. The presence of gaps covered with an insulating layer for the electric field on the electrodes allows the passing of RBCs through gaps, while relatively large WBCs (cultured cultured human acute monocytic leukemia cell line (THP-1 cells)) flowed along the slanted separator without passing through the gaps and arrived at an edge in the channel. The passage efficiency for RBCs through the gaps and the arrival efficiency for THP-1 cells to the upper edge in the channel were estimated and found to be 91% and 93%, respectively.

Dielectrophoretic assembly and separation of particles and cells in continuous flow

“…According to the interaction between particles and electric eld, DEP separation approaches can be divided into the following three types: pDEP-force based, [27][28][29] nDEPforce based, 30,31 and hybrid DEP force based methods. 21,32,33 DEP separation techniques have outstanding advantages in the selection of targeted cells and particles, which can effectively address the important issues in many elds, such as biology, 1,2 medicine, 7 and the environment. 5,6 However, the assembly of cells under DEP force is inevitable, and formation of cell chains has certain inuences on the separation results.…”

Continuous Particle Separation Driven by 3D Ag-PDMS Electrodes with Dielectric Electrophoretic Force Coupled with Inertia Force

“…Many techniques have been developed in microfluidics, including inertial microfluidics [7], deterministic lateral displacement [8], hydrophoresis [9,10], optical [11], dielectrophoresis (DEP) [12], surface acoustic waves [13], and magnetic force to achieve precise control and sorting of detection objects such as particles and cells with microfluidic chips. Among these separation techniques, DEP has attracted more attention due to its advantages, such as label-free and non-contact forces on particles [14,15]. In DEP, the internal charge of particles in fluid is induced to polarize and move in the positive or negative direction of the electric field gradient after the particles are loaded with the non-uniform electric field [16].…”

Implementation of an Integrated Dielectrophoretic and Magnetophoretic Microfluidic Chip for CTC Isolation

“…Compared with the above-mentioned techniques, microfluidics is becoming one of the most popular technologies to provide solutions for biological applications, such as manipulation and concentration of cells [ 3 , 13 ], bacteria [ 14 ], and 3D bioprinting [ 15 ]. Based on different physical mechanisms, various methods including dielectrophoresis [ 16 , 17 , 18 , 19 ], deterministic lateral displacement (DLD) [ 20 , 21 , 22 , 23 ], hydrodynamic lift [ 24 ], magnetophoresis [ 25 ], centrifugation [ 6 ], and acoustic [ 26 ] have been employed for cell separation in microfluidic chips, which benefit from bio-compatibility, low sample consumption, the tiny size of platform, and an easy process to carry out [ 27 , 28 ]. Moreover, due to the free of cell pre-label and decreasing cell damage, label-free cell sorting techniques in microfluidic devices are widely used for the separation of cells based on their specified physical differences [ 12 ].…”