1
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Mohammadali R, Bayareh M, Nadooshan AA. Performance optimization of a DLD microfluidic device for separating deformable CTCs. Electrophoresis 2024. [PMID: 39140230 DOI: 10.1002/elps.202400136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 07/11/2024] [Accepted: 07/25/2024] [Indexed: 08/15/2024]
Abstract
Deterministic lateral displacement (DLD) microfluidic devices work based on the streamlines created by an array of micro-posts. The configuration of pillars alters the isolation efficiency of these devices. The present paper optimizes the performance of a DLD device for isolating deformable circulating tumor cells. The input variables include cell diameter (d), Young's modulus (E s ${E}_s$ ), Reynolds number (Re), and tan θ, where θ is the tilted angle of micro-posts. The output, which is the response of the system, is DLD. The numerical simulation results are employed to optimize the device using the response surface method, leading to the proposition of a correlation to estimate DLD as a function of input variables. It is demonstrated that the maximum and minimum impacts on cell lateral displacement correspond toE s ${E}_s$ and Re, respectively.
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Affiliation(s)
- Roya Mohammadali
- Department of Mechanical Engineering, Shahrekord University, Shahrekord, Iran
| | - Morteza Bayareh
- Department of Mechanical Engineering, Shahrekord University, Shahrekord, Iran
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2
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Mohammadali R, Bayareh M. Deformability-Based Isolation of Circulating Tumor Cells in Spiral Microchannels. MICROMACHINES 2023; 14:2111. [PMID: 38004968 PMCID: PMC10672993 DOI: 10.3390/mi14112111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/08/2023] [Accepted: 11/17/2023] [Indexed: 11/26/2023]
Abstract
The isolation of circulating tumor cells (CTCs) and their analysis are crucial for the preliminary identification of invasive cancer. One of the effective properties that can be utilized to isolate CTCs is their deformability. In this paper, inertial-based spiral microchannels with various numbers of loops are employed to sort deformable CTCs using the finite element method (FEM) and an arbitrary Lagrangian-Eulerian (ALE) approach. The influences of cell deformability, cell size, number of loops, and channel depth on the hydrodynamic behavior of CTCs are discussed. The results demonstrate that the trajectory of cells is affected by the above factors when passing through the spiral channel. This approach can be utilized for sorting and isolating label-free deformable biological cells at large scales in clinical systems.
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Affiliation(s)
| | - Morteza Bayareh
- Department of Mechanical Engineering, Shahrekord University, Shahrekord 88186-34141, Iran;
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3
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He X, Wang P, Shi L, Zhou T, Wen L. Electrokinetic translocation of a deformable nanoparticle controlled by field effect in nanopores. Electrophoresis 2021; 42:2197-2205. [PMID: 34409625 DOI: 10.1002/elps.202100107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 08/05/2021] [Accepted: 08/10/2021] [Indexed: 12/27/2022]
Abstract
Nanopores have become a popular single-molecule manipulation and detection technology. In this paper, we have constructed a continuum model of the nanopore; the arbitrary Lagrangian-Eulerian (ALE) method is used to describe the motion of particles and fluid. The mathematical model couples the stress-strain equation for the dynamics of a deformable particle, the Poisson equation for the electric field, the Navier-Stokes equations for the flow field, and the Nernst-Planck equations for ionic transport. Based on the model, the mechanism of field-effect regulation of particles passing through a nanopore is investigated. The results show that the transport of particles which is controlled by the field effect depends on the electroosmotic flow (EOF) generated by the gate electrode in the nanopore and the electrostatic interaction between the nanopore and particles. That also explains the asymmetry of particle transport velocity in the nanopore with a gate electrode. When the gate potential is negative, or the gate electrode length is small, the maximum deformation of the particles is increased. The field-effect regulation in the nanopore provides an active and compatible method for nanopore detection, and provides a convenient method for the active control of the particle deformation in the nanopore.
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Affiliation(s)
- Xiaohan He
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Pengcheng Wang
- Department of Mechanical Engineering, University of Houston, Houston, Texas, USA
| | - Liuyong Shi
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Teng Zhou
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Liping Wen
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, P. R. China
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4
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Ashrafizadeh SN, Seifollahi Z, Ganjizade A, Sadeghi A. Electrophoresis of spherical soft particles in electrolyte solutions: A review. Electrophoresis 2019; 41:81-103. [DOI: 10.1002/elps.201900236] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 11/11/2019] [Accepted: 11/11/2019] [Indexed: 02/01/2023]
Affiliation(s)
- Seyed Nezameddin Ashrafizadeh
- Research Lab for Advanced Separation ProcessesDepartment of Chemical EngineeringIran University of Science and Technology Tehran Iran
| | - Zahra Seifollahi
- Research Lab for Advanced Separation ProcessesDepartment of Chemical EngineeringIran University of Science and Technology Tehran Iran
| | - Ardalan Ganjizade
- Research Lab for Advanced Separation ProcessesDepartment of Chemical EngineeringIran University of Science and Technology Tehran Iran
| | - Arman Sadeghi
- Department of Mechanical EngineeringUniversity of Kurdistan Sanandaj Iran
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5
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Zhou T, Ji X, Shi L, Zhang X, Song Y, Joo SW. AC dielectrophoretic deformable particle‐particle interactions and their relative motions. Electrophoresis 2019; 41:952-958. [DOI: 10.1002/elps.201900266] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/01/2019] [Accepted: 09/07/2019] [Indexed: 01/07/2023]
Affiliation(s)
- Teng Zhou
- Mechanical and Electrical Engineering CollegeHainan University Haikou Hainan P. R. China
| | - Xiang Ji
- Mechanical and Electrical Engineering CollegeHainan University Haikou Hainan P. R. China
| | - Liuyong Shi
- Mechanical and Electrical Engineering CollegeHainan University Haikou Hainan P. R. China
| | - Xianman Zhang
- Mechanical and Electrical Engineering CollegeHainan University Haikou Hainan P. R. China
| | - Yongxin Song
- Department of Marine EngineeringDalian Maritime University Dalian P. R. China
| | - Sang Woo Joo
- School of Mechanical EngineeringYeungnam University Gyongsan Korea
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6
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Zhou T, Ji X, Shi L, Zhang X, Deng Y, Joo SW. Dielectrophoretic choking phenomenon in a converging-diverging microchannel for Janus particles. Electrophoresis 2018; 40:993-999. [PMID: 30371959 DOI: 10.1002/elps.201800368] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 11/10/2022]
Abstract
The dielectrophoretic (DEP) choking phenomenon is revisited for Janus particles that are transported electrokinetically through a microchannel constriction by a direct-current (DC) electric field. The negative DEP force that would block a particle with a diameter significantly smaller than that of the constriction at its inlet is seen to be relaxed by the rotation of the Janus particle in a direction that minimizes the magnitude of the DEP force. This allows the particle to pass through the constriction completely. An arbitrary Lagrangian-Eulerian (ALE) numerical method is used to solve the nonlinearly coupled electric field, flow field, and moving particle, and the DEP force is calculated by the Maxwell stress tensor (MST) method. The results show how Janus particles with non-uniform surface potentials overcome the DEP force and present new conditions for the DEP choking by a parametric study. Particle transportation through microchannel constrictions is ubiquitous, and particle surface properties are more likely to be non-uniform than not in practical applications. This study provides new insights of importance for non-uniform particles transported electrokinetically in a microdevice.
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Affiliation(s)
- Teng Zhou
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Xiang Ji
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Liuyong Shi
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Xianman Zhang
- Mechanical and Electrical Engineering College, Hainan University, Haikou, Hainan, P. R. China
| | - Yongbo Deng
- Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP), Chinese Academy of Science, Changchun, Jilin, P. R. China
| | - Sang Woo Joo
- School of Mechanical Engineering, Yeungnam University, Gyongsan, Korea
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7
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Ji X, Xu L, Zhou T, Shi L, Deng Y, Li J. Numerical Investigation of DC Dielectrophoretic Deformable Particle⁻Particle Interactions and Assembly. MICROMACHINES 2018; 9:E260. [PMID: 30424193 PMCID: PMC6187325 DOI: 10.3390/mi9060260] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 05/20/2018] [Accepted: 05/22/2018] [Indexed: 12/26/2022]
Abstract
In a non-uniform electric field, the surface charge of the deformable particle is polarized, resulting in the dielectrophoretic force acting on the surface of the particle, which causes the electrophoresis. Due to dielectrophoretic force, the two deformable particles approach each other, and distort the flow field between them, which cause the hydrodynamic force correspondingly. The dielectrophoresis (DEP) force and the hydrodynamic force together form the net force acting on the particles. In this paper, based on a thin electric double layer (EDL) assumption, we developed a mathematical model under the arbitrary Lagrangian⁻Eulerian (ALE) numerical approach method to simulate the flow field, electric field, and deformable particles simultaneously. Simulation results show that, when two deformable particles' distances are in a certain range, no matter the initial position of the two particles immersed in the fluid field, the particles will eventually form a particle⁻particle chain parallel to the direction of the electric field. In actual experiments, the biological cells used are deformable. Compared with the previous study on the DEP motion of the rigid particles, the research conclusion of this paper provides a more rigorous reference for the design of microfluidics.
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Affiliation(s)
- Xiang Ji
- Mechanical and Electrical Engineering College, Hainan University, Haikou 570228, China.
| | - Li Xu
- School of Energy and Power Engineering, Wuhan University of Technology, Wuhan 430070, China.
| | - Teng Zhou
- Mechanical and Electrical Engineering College, Hainan University, Haikou 570228, China.
| | - Liuyong Shi
- Mechanical and Electrical Engineering College, Hainan University, Haikou 570228, China.
| | - Yongbo Deng
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP), Chinese Academy of Sciences, Changchun 130033, China.
| | - Jie Li
- School of Energy and Power Engineering, Wuhan University of Technology, Wuhan 430070, China.
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8
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Zhou T, Ge J, Shi L, Fan J, Liu Z, Woo Joo S. Dielectrophoretic choking phenomenon of a deformable particle in a converging-diverging microchannel. Electrophoresis 2017; 39:590-596. [DOI: 10.1002/elps.201700250] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Teng Zhou
- Mechanical and Electrical Engineering College; Hainan University; Haikou Hainan P. R. China
| | - Jian Ge
- Mechanical and Electrical Engineering College; Hainan University; Haikou Hainan P. R. China
| | - Liuyong Shi
- Mechanical and Electrical Engineering College; Hainan University; Haikou Hainan P. R. China
| | - Junqing Fan
- Mechanical and Electrical Engineering College; Hainan University; Haikou Hainan P. R. China
| | - Zhenyu Liu
- Changchun Institute of Optics; Fine Mechanics and Physics (CIOMP); Chinese Academy of Science; Changchun Jilin P. R. China
| | - Sang Woo Joo
- School of Mechanical Engineering; Yeungnam University; Gyongsan Korea
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9
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Deformability-Based Electrokinetic Particle Separation. MICROMACHINES 2016; 7:mi7090170. [PMID: 30404343 PMCID: PMC6189855 DOI: 10.3390/mi7090170] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 01/12/2023]
Abstract
Deformability is an effective property that can be used in the separation of colloidal particles and cells. In this study, a microfluidic device is proposed and tested numerically for the sorting of deformable particles of various degrees. The separation process is numerically investigated by a direct numerical simulation of the fluid–particle–electric field interactions with an arbitrary Lagrangian–Eulerian finite-element method. The separation performance is investigated with the shear modulus of particles, the strength of the applied electric field, and the design of the contracted microfluidic devices as the main parameters. The results show that the particles with different shear moduli take different shapes and trajectories when passing through a microchannel contraction, enabling the separation of particles based on their difference in deformability.
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10
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Yariv E. Dielectrophoretic sphere-wall repulsion due to a uniform electric field. SOFT MATTER 2016; 12:6277-6284. [PMID: 27384257 DOI: 10.1039/c6sm00462h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
When a zero-net-charge particle is placed under a uniform electric field, the decay of the Maxwell stress with the third power of distance ensures a nil electric force. A nonzero force may nonetheless be generated in the presence of a planar wall due to a mechanism which resembles conventional dielectrophoresis under nonuniform fields. In the prototypical case of a spherical particle this force acts perpendicular to the wall; its magnitude depends upon the pertinent boundary conditions governing the electric potential. When a particle is suspended in an electrolyte solution, where the double-layer structure ensures zero net charge, these conditions are electrokinetic in nature; they involve a balance between bulk conduction and diffusion, represented by normal derivatives, and an effective surface-conduction mechanism, represented by surface-Laplacian terms whose magnitude is quantified by appropriate Dukhin numbers. The dimensionless force depends upon the particle and wall Dukhin numbers as well as the ratio λ of the size of the particle to its distance from the wall. The remote-particle limit λ ≪ 1 is addressed using successive reflections. Calculation of the first few terms in the asymptotic expansion of the force only requires the evaluation of a single reflection from the wall. The leading-order term, scaling as λ(4), is repulsive, with a magnitude that varies non-monotonically with the particle Dukhin number and is independent of the wall Dukhin number. Surface conditions on the wall enter only at the O(λ(5)) leading-order correction.
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Affiliation(s)
- Ehud Yariv
- Department of Mathematics, Technion - Israel Institute of Technology, Haifa 32000, Israel.
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11
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CFD design of a microfluidic device for continuous dielectrophoretic separation of charged gold nanoparticles. J Taiwan Inst Chem Eng 2016. [DOI: 10.1016/j.jtice.2015.05.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Guo J, Chen L, Ai Y, Cheng Y, Li CM, Kang Y, Wang Z. Numerical and experimental characterization of solid-state micropore-based cytometer for detection and enumeration of biological cells. Electrophoresis 2015; 36:737-43. [PMID: 25488493 DOI: 10.1002/elps.201400376] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 11/25/2014] [Accepted: 11/27/2014] [Indexed: 10/24/2022]
Abstract
Portable diagnostic devices have emerged as important tools in various biomedical applications since they can provide an effective solution for low-cost and rapid clinical diagnosis. In this paper, we present a micropore-based resistive cytometer for the detection and enumeration of biological cells. The proposed device was fabricated on a silicon wafer by a standard microelectromechanical system processing technology, which enables a mass production of the proposed chip. The working principle of this cytometer is based upon a bias potential modulated pulse, originating from the biological particle's physical blockage of the micropore. Polystyrene particles of different sizes (7, 10, and 16 μm) were used to test and calibrate the proposed device. A finite element simulation was developed to predict the bias potential modulated pulse (peak amplitude vs. pulse bandwidth), which can provide critical insight into the design of this microfluidic flow cytometer. Furthermore, HeLa cells (a type of tumor cell lines) spiked in a suspension of blood cells, including red blood cells and white blood cells, were used to assess the performance for detecting and counting tumor cells. The proposed microfluidic flow cytometer is able to provide a promising platform to address the current unmet need for point-of-care clinical diagnosis.
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Affiliation(s)
- Jinhong Guo
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, P. R. China; Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore
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13
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Yan S, Zhang J, Alici G, Du H, Zhu Y, Li W. Isolating plasma from blood using a dielectrophoresis-active hydrophoretic device. LAB ON A CHIP 2014; 14:2993-3003. [PMID: 24939716 DOI: 10.1039/c4lc00343h] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Plasma is a complex substance that contains proteins and circulating nucleic acids and viruses that can be utilised for clinical diagnostics, albeit a precise analysis depends on the plasma being totally free of cells. We proposed the use of a dielectrophoresis (DEP)-active hydrophoretic method to isolate plasma from blood in a high-throughput manner. This microfluidic device consists of anisotropic microstructures embedded on the top of the channel which generate lateral pressure gradients while interdigitised electrodes lay on the bottom of the channel which can push particles or cells into a higher level using a negative DEP force. Large and small particles or cells (3 μm and 10 μm particles, and red blood cells, white blood cells, and platelets) can be focused at the same time in our DEP-active hydrophoretic device at an appropriate flow rate and applied voltage. Based on this principle, all the blood cells were filtrated from whole blood and then the plasma was extracted with a purity of 94.2% and a yield of 16.5% at a flow rate of 10 μL min(-1). This solved the challenging problem caused by the relatively low throughput of the DEP based device. Our DEP-active hydrophoretic device is a flexible and tunable system that can control the lateral positions of particles by modulating the external voltages without redesigning and fabricating a new channel, and because it is easy to operate, it is easily compatible with other microfluidic platforms that are used for further detection.
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Affiliation(s)
- Sheng Yan
- School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
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On-chip high-throughput manipulation of particles in a dielectrophoresis-active hydrophoretic focuser. Sci Rep 2014; 4:5060. [PMID: 24862936 PMCID: PMC4033927 DOI: 10.1038/srep05060] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 05/07/2014] [Indexed: 11/08/2022] Open
Abstract
This paper proposes a novel concept of dielectrophoresis (DEP)-active hydrophoretic focusing of micro-particles and murine erythroleukemia (MEL) cells. The DEP-active hydrophoretic platform consists of crescent shaped grooves and interdigitated electrodes that generate lateral pressure gradients. These embedded electrodes exert a negative DEP force onto the particles by pushing them into a narrow space in the channel where the particle to groove interaction is intensive and hydrophoretic ordering occurs. Particles passing through the microfluidic device are directed towards the sidewalls of the channel. The critical limitation of DEP operating at a low flow rate and the specific hydrophoretic device for focusing particles of given sizes were overcome with the proposed microfluidic device. The focusing pattern can be modulated by varying the voltage. High throughput was achieved (maximum flow rate ~150 μL min(-1)) with good focusing performance. The non-spherical MEL cells were utilised to verify the effectiveness of the DEP-active hydrophoretic device.
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15
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Moncada-Hernandez H, Nagler E, Minerick AR. Theoretical and experimental examination of particle-particle interaction effects on induced dipole moments and dielectrophoretic responses of multiple particle chains. Electrophoresis 2014; 35:1803-13. [DOI: 10.1002/elps.201300636] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 03/14/2014] [Accepted: 03/17/2014] [Indexed: 11/07/2022]
Affiliation(s)
- Hector Moncada-Hernandez
- Biointeractive Systems and BioMEMS; Tecnológico de Monterrey; Campus Monterrey; Monterrey N.L. México
| | - Eliot Nagler
- MD-ERL; Michigan Technological University; Houghton MI USA
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Ai Y, Zeng Z, Qian S. Direct numerical simulation of AC dielectrophoretic particle–particle interactive motions. J Colloid Interface Sci 2014; 417:72-9. [DOI: 10.1016/j.jcis.2013.11.034] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 11/09/2013] [Accepted: 11/11/2013] [Indexed: 11/26/2022]
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17
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Electroformation and electrofusion of giant vesicles in a microfluidic device. Colloids Surf B Biointerfaces 2013; 110:81-7. [PMID: 23711780 DOI: 10.1016/j.colsurfb.2013.04.042] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 04/10/2013] [Accepted: 04/16/2013] [Indexed: 01/25/2023]
Abstract
Electroformation and electrofusion of giant vesicles with diameters of 10-20μm have been performed in a microfluidic device with high-density microelectrodes forming the sidewalls of the microchannel. Electroformation of giant vesicles by a solution mixture of phosphatidylcholine (PC) and cholesterol (Chol) with different concentrations under AC electric field was investigated. Under the conditions of 0.5-12mg/mL PC and 0.1-2.4mg/mL Chol, vesicles were electroformed by the AC electric field imposed. About 60% electroformed vesicles were giant (unilamellar) vesicles with diameters 10-20μm. The eletroformed vesicles were collected from the chip, re-suspended in fresh buffer, and then separated by centrifugation to segregate the ones with desired diameters (10-20μm). Electrofusion of the giant vesicles was conducted in the same chip. Vesicles were aligned to form pairs under AC electric field due to positive dielectrophoresis, and the paired vesicles were subsequently fused upon the application of high strength electrical pulses. The alignment and fusion efficiencies were, respectively, about 50% and 20%.
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18
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Tseng S, Lin CY, Hsu JP, Yeh LH. Electrophoresis of deformable polyelectrolytes in a nanofluidic channel. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:2446-2454. [PMID: 23379259 DOI: 10.1021/la304842x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The influence of the shape of a polyelectrolyte (PE) on its electrophoretic behavior in a nanofluidic channel is investigated by considering the translocation of a deformable ellipsoidal PE along the axis of a cylindrical nanochannel. A continuum model comprising a Poisson equation for the electric potential, Nernst-Planck equations for the ionic concentrations, and modified Stokes equations for the flow field is adopted. The effects of the PE shape, boundary, bulk ionic concentration, counterion condensation, electroosmotic retardation flow, and electroosmotic flow (EOF) on the PE mobility are discussed. Several interesting behaviors are observed. For example, if the nanochannel is uncharged and the double layer is thick, then the PE mobility increases (decreases) with increasing double-layer thickness for a smaller (larger) boundary, which has not been reported previously. If the nanochannel is negatively charged and the double layer is thick, then a negatively charged PE moves in the direction of the applied electric field. The results gathered provide necessary information for both the interpretation of experimental data and the design of nanochannel-based sensing devices.
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Affiliation(s)
- Shiojenn Tseng
- Department of Mathematics, Tamkang University, Tamsui, Taipei 25137, Taiwan
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19
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Guo J, Pui TS, Rahman ARA, Kang Y. 3D numerical simulation of a Coulter counter array with analysis of electrokinetic forces. Electrophoresis 2012; 34:417-24. [DOI: 10.1002/elps.201200418] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 09/11/2012] [Accepted: 09/18/2012] [Indexed: 12/20/2022]
Affiliation(s)
| | - Tze Sian Pui
- Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research); Singapore
| | - Abdur Rub Abdur Rahman
- Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research); Singapore
| | - Yuejun Kang
- School of Chemical and Biomedical Engineering; Nanyang Technological University; Singapore
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