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Hu S, Wang Y, Wang Y, Chen X, Tong R. Dielectrophoretic separation and purification: From colloid and biological particles to droplets. J Chromatogr A 2024; 1731:465155. [PMID: 39032216 DOI: 10.1016/j.chroma.2024.465155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 07/06/2024] [Accepted: 07/08/2024] [Indexed: 07/22/2024]
Abstract
It is indispensable to realize the high level of purification and separation, so that objective particles, such as malignant cells, harmful bacteria, and special proteins or biological molecules, could satisfy the high precise measurement in the pharmaceutical analysis, clinical diagnosis, targeted therapy, and food defense. In addition, this could reveal the intrinsic nature and evolution mechanisms of individual biological variations. Consequently, many techniques related to optical tweezers, microfluidics, acoustophoresis, and electrokinetics can be broadly used to achieve micro- and nano-scale particle separations. Dielectrophoresis (DEP) has been used for various manipulation, concentration, transport, and separation processes of biological particles owing to its early development, mature theory, low cost, and high throughput. Although numerous reviews have discussed the biological applications of DEP techniques, comprehensive descriptions of micro- and nano-scale particle separations feature less frequently in the literature. Therefore, this review summarizes the current state of particle separation attention to relevant technological developments and innovation, including theoretical simulation, microchannel structure, electrode material, pattern and its layout. Moreover, a brief overview of separation applications using DEP in combination with other technologies is also provided. Finally, conclusions, future guidelines, and suggestions for potential promotion are highlighted.
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Affiliation(s)
- Sheng Hu
- College of Information Science and Engineering, Northeastern University, Shenyang, China; Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, China.
| | - Yangcheng Wang
- College of Information Science and Engineering, Northeastern University, Shenyang, China
| | - Yanzhe Wang
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, China
| | - Xiaoming Chen
- College of Information Science and Engineering, Northeastern University, Shenyang, China; Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, China
| | - Ruijie Tong
- College of Information Science and Engineering, Northeastern University, Shenyang, China; Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, China
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2
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Deivasigamani R, Mohd Maidin NN, Abdul Nasir NS, Abdulhameed A, Ahmad Kayani AB, Mohamed MA, Buyong MR. A correlation of conductivity medium and bioparticle viability on dielectrophoresis-based biomedical applications. Electrophoresis 2023; 44:573-620. [PMID: 36604943 DOI: 10.1002/elps.202200203] [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: 08/12/2022] [Revised: 11/28/2022] [Accepted: 12/26/2022] [Indexed: 01/07/2023]
Abstract
Dielectrophoresis (DEP) bioparticle research has progressed from micro to nano levels. It has proven to be a promising and powerful cell manipulation method with an accurate, quick, inexpensive, and label-free technique for therapeutic purposes. DEP, an electrokinetic phenomenon, induces particle movement as a result of polarization effects in a nonuniform electrical field. This review focuses on current research in the biomedical field that demonstrates a practical approach to DEP in terms of cell separation, trapping, discrimination, and enrichment under the influence of the conductive medium in correlation with bioparticle viability. The current review aims to provide readers with an in-depth knowledge of the fundamental theory and principles of the DEP technique, which is influenced by conductive medium and to identify and demonstrate the biomedical application areas. The high conductivity of physiological fluids presents obstacles and opportunities, followed by bioparticle viability in an electric field elaborated in detail. Finally, the drawbacks of DEP-based systems and the outlook for the future are addressed. This article will aid in advancing technology by bridging the gap between bioscience and engineering. We hope the insights presented in this review will improve cell suspension medium and promote DEP-viable bioparticle manipulation for health-care diagnostics and therapeutics.
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Affiliation(s)
- Revathy Deivasigamani
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia
| | - Nur Nasyifa Mohd Maidin
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia
| | - Nur Shahira Abdul Nasir
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia
| | | | - Aminuddin Bin Ahmad Kayani
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia.,ARC Research Hub for Connected Sensors for Health, RMIT University, Melbourne, Australia
| | - Mohd Ambri Mohamed
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia
| | - Muhamad Ramdzan Buyong
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia
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3
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Derksen J, Viefhues M. Parallelized continuous flow dielectrophoretic separation of DNA. Electrophoresis 2022. [DOI: 10.1002/elps.202200174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/16/2022] [Accepted: 09/28/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Jakob Derksen
- Experimental Biophysics and Applied Nanoscience, Faculty of Physics Bielefeld University Bielefeld Germany
- Mechanobiology of Thrombosis and Hemostasis, Faculty of Lifesciences University of Siegen Siegen Germany
| | - Martina Viefhues
- Experimental Biophysics and Applied Nanoscience, Faculty of Physics Bielefeld University Bielefeld Germany
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Kwizera EA, Ou W, Lee S, Stewart S, Shamul JG, Xu J, Tait N, Tkaczuk KHR, He X. Greatly Enhanced CTC Culture Enabled by Capturing CTC Heterogeneity Using a PEGylated PDMS-Titanium-Gold Electromicrofluidic Device with Glutathione-Controlled Gentle Cell Release. ACS NANO 2022; 16:11374-11391. [PMID: 35797466 PMCID: PMC9649890 DOI: 10.1021/acsnano.2c05195] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The circulating tumor cells (CTCs, the root cause of cancer metastasis and poor cancer prognosis) are very difficult to culture for scale-up in vitro, which has hampered their use in cancer research/prognosis and patient-specific therapeutic development. Herein, we report a robust electromicrofluidic chip for not only efficient capture of heterogeneous (EpCAM+ and CD44+) CTCs with high purity but also glutathione-controlled gentle release of the CTCs with high efficiency and viability. This is enabled by coating the polydimethylsiloxane (PDMS) surface in the device with a 10 nm gold layer through a 4 nm titanium coupling layer, for convenient PEGylation and linkage of capture antibodies via the thiol-gold chemistry. Surprisingly, the percentage of EpCAM+ mammary CTCs can be as low as ∼35% (∼70% on average), showing that the commonly used approach of capturing CTCs with EpCAM alone may miss many EpCAM- CTCs. Furthermore, the CD44+ CTCs can be cultured to form 3D spheroids efficiently for scale-up. In contrast, the CTCs captured with EpCAM alone are poor in proliferation in vitro, consistent with the literature. By capture of the CTC heterogeneity, the percentage of stage IV patients whose CTCs can be successfully cultured/scaled up is improved from 12.5% to 68.8%. These findings demonstrate that the common practice of CTC capture with EpCAM alone misses the CTC heterogeneity including the critical CD44+ CTCs. This study may be valuable to the procurement and scale-up of heterogeneous CTCs, to facilitate the understanding of cancer metastasis and the development of cancer metastasis-targeted personalized cancer therapies conveniently via the minimally invasive liquid/blood biopsy.
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Affiliation(s)
- Elyahb A Kwizera
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Wenquan Ou
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Sojeong Lee
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Samantha Stewart
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - James G Shamul
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Jiangsheng Xu
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Nancy Tait
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland 21201, United States
| | - Katherine H R Tkaczuk
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland 21201, United States
| | - Xiaoming He
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland 21201, United States
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Nakabayashi R, Eguchi M. Evaluation of Isomotive Insulator-Based Dielectrophoretic Device by Measuring the Particle Velocity. SENSORS 2022; 22:s22041533. [PMID: 35214434 PMCID: PMC8880631 DOI: 10.3390/s22041533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/09/2022] [Accepted: 02/14/2022] [Indexed: 12/03/2022]
Abstract
Many dielectrophoretic (DEP) devices for biomedical application have been suggested, such as the separation, concentration, and detection of biological cells or molecules. Most of these devices utilize the difference in their DEP properties. However, single-cell analysis is required to evaluate individual properties. Therefore, this paper proposed a modified isomotive insulator-based DEP (iDEP) creek-gap device for straightforward single-cell analysis, which is capable of measurement at a wide frequency band. The proposed iDEP device generates more constant particle velocity than the previous study. The insulator was fabricated using backside exposure for accurate forming. We measured the distribution of the particle velocity and frequency property, using homogeneous polystyrene particles to verify the effectiveness of the proposed device. The results show that the particle velocity distribution was consistent with the distribution of the numerically calculated electric field square (∇Erms2). Furthermore, the velocity measurement, at a wide frequency band, from 10 Hz to 20 MHz, was performed because of the long distance between electrodes. These results suggest that the prop-erties of various particles or cells can be obtained by simple measurement using the proposed device.
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Affiliation(s)
- Ryu Nakabayashi
- Advanced Course, Project Design Engineering, National Institute of Technology (KOSEN), Kure College, 2-2-11, Aga-Minami, Kure, Hiroshima 737-8506, Japan;
| | - Masanori Eguchi
- Department of Electrical Engineering and Information Science, National Institute of Technology (KOSEN), Kure College, 2-2-11, Aga-Minami, Kure, Hiroshima 737-8506, Japan
- Correspondence:
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6
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Fabrication of a new all-in-one microfluidic dielectrophoresis integrated chip and living cell separation. iScience 2022; 25:103776. [PMID: 35146391 PMCID: PMC8819401 DOI: 10.1016/j.isci.2022.103776] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 11/16/2021] [Accepted: 01/11/2022] [Indexed: 11/22/2022] Open
Abstract
Microfluidic dielectrophoresis (DEP) technology has been applied to many devices to perform label-free target cell separation. Cells separated by these devices are used in laboratories, mainly for medical research. The present study designed a microfluidic DEP device to fabricate a rapid and semiautomated cell separation system in conjunction with microscopy to enumerate the separated cells. With this device, we efficiently segregated bacterial cells from liquid products and enriched one cell type from two mixed eukaryotic cell types. The device eliminated sample pretreatment and established cell separation by all-in-one operation in a lab-on-chip, requiring only a small sample volume (0.5–1 mL) to enumerate the target cells and completing the entire separation process within 30 min. Such a rapid cell separation technique is in high demand by many researchers to promptly characterize the target cells. A new all-in-one microfluidic dielectrophoresis integrated chip is fabricated Simultaneous operation of buffer exchange and continuous cell separation on a chip Chip’s cell separation performance is evaluated with bacterial and eukaryotic cells
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Kong TF, Tan PY, Tay BZ, Shen X, Marcos. Bacteria and cancer cell pearl chain under dielectrophoresis. Electrophoresis 2021; 42:1070-1078. [PMID: 33442876 DOI: 10.1002/elps.202000277] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/14/2020] [Accepted: 01/05/2021] [Indexed: 11/10/2022]
Abstract
In this work, we aim to observe and study the physics of bacteria and cancer cells pearl chain formation under dielectrophoresis (DEP). Experimentally, we visualized the formation of Bacillus subtilis bacterial pearl chain and human breast cancer cell (MCF-7) chain under positive and negative dielectrophoretic force, respectively. Through a simple simulation with creeping flow, AC/DC electric fields, and particle tracing modules in COMSOL, we examined the mechanism by which bacteria self-organize into a pearl chain across the gap between two electrodes via DEP. Our simulation results reveal that the region of greatest positive DEP force shifts from the electrode edge to the leading edge of the pearl chain, thus guiding the trajectories of free-flowing particles toward the leading edge via positive DEP. Our findings additionally highlight the mechanism why the free-flowing particles are more likely to join the existing pearl chain rather than starting a new pearl chain. This phenomenon is primarily due to the increase in magnitude of electric field gradient, and hence DEP force exerted, with the shortening gap between the pearl chain leading edge and the adjacent electrode. The findings shed light on the observed behavior of preferential pearl chain formation across electrode gaps.
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Affiliation(s)
- Tian Fook Kong
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Pei Yen Tan
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Benjamin Zikai Tay
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore.,Interdisciplinary Graduate Programme, NTU Institute for Health Technologies (HealthTech NTU), Nanyang Technological University, Singapore
| | - Xinhui Shen
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
| | - Marcos
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
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Dielectrophoresis-field flow fractionation for separation of particles: A critical review. J Chromatogr A 2020; 1637:461799. [PMID: 33385744 DOI: 10.1016/j.chroma.2020.461799] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 01/22/2023]
Abstract
Dielectrophoresis-field flow fractionation (DEP-FFF) has emerged as an efficient in-vitro, non-invasive, and label-free mechanism to manipulate a variety of nano- and micro-scaled particles in a continuous-flow manner. The technique is mainly used to fractionate particles/cells based on differences in their sizes and/or dielectric properties by employing dielectrophoretic force as an external force field applied perpendicular to the flow direction. The dielectrophoretic force is the result of a spatially non-uniform electric field in the microchannel that can be generated either by exploiting microchannel geometry or using special arrangements of microelectrode arrays. Several two-dimensional (e.g., coplanar interdigitated, castellated) and three-dimensional (e.g., top-bottom, side-wall) microelectrode designs have been successfully utilized to perform fractionation of heterogeneous samples. Although originally introduced as a separation technique, DEP-FFF has attracted increasing interest in performing other important operations such as switching, focusing, dipping, and surface functionalization of target particles. Nonetheless, the technique still suffers from limitations such as low throughput and joule heating. By comparatively analyzing recent developments that address these shortcomings, this work is a step forward towards realizing the full potential of DEP-FFF as an ideal candidate for point-of-care (POC) devices with diverse applications in the fields of biomedical, chemical, and environmental engineering.
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Benhal P, Quashie D, Kim Y, Ali J. Insulator Based Dielectrophoresis: Micro, Nano, and Molecular Scale Biological Applications. SENSORS (BASEL, SWITZERLAND) 2020; 20:E5095. [PMID: 32906803 PMCID: PMC7570478 DOI: 10.3390/s20185095] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 08/16/2020] [Accepted: 09/04/2020] [Indexed: 12/31/2022]
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.
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Affiliation(s)
- Prateek Benhal
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, FL 32310, USA;
- National High Magnetic Field Laboratory, Tallahassee, FL 32310, USA
| | - David Quashie
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, FL 32310, USA;
- National High Magnetic Field Laboratory, Tallahassee, FL 32310, USA
| | - Yoontae Kim
- American Dental Association Science & Research Institute, Gaithersburg, MD 20899, USA;
| | - Jamel Ali
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, FL 32310, USA;
- National High Magnetic Field Laboratory, Tallahassee, FL 32310, USA
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High-Sensitivity in Dielectrophoresis Separations. MICROMACHINES 2020; 11:mi11040391. [PMID: 32283618 PMCID: PMC7231031 DOI: 10.3390/mi11040391] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/19/2020] [Accepted: 03/26/2020] [Indexed: 01/27/2023]
Abstract
The applications of dielectrophoretic (DEP) techniques for the manipulation of cells in a label-free fashion within microfluidic systems continue to grow. However, a limited number of methods exist for making highly sensitive separations that can isolate subtle phenotypic differences within a population of cells. This paper explores efforts to leverage that most compelling aspect of DEP—an actuation force that depends on particle electrical properties—in the background of phenotypic variations in cell size. Several promising approaches, centering around the application of multiple electric fields with spatially mapped magnitude and/or frequencies, are expanding the capability of DEP cell separation.
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11
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Zhang J, Song Z, Liu Q, Song Y. Recent advances in dielectrophoresis‐based cell viability assessment. Electrophoresis 2020; 41:917-932. [DOI: 10.1002/elps.201900340] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/28/2019] [Accepted: 11/29/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Junyan Zhang
- Department of Marine EngineeringDalian Maritime University Dalian P. R. China
| | - Zhenyu Song
- Department of RadiotherapyJiaozhou Central Hospital Qingdao P. R. China
| | - Qinxin Liu
- Department of Marine EngineeringDalian Maritime University Dalian P. R. China
| | - Yongxin Song
- Department of Marine EngineeringDalian Maritime University Dalian P. R. China
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12
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Sequential Cell-Processing System by Integrating Hydrodynamic Purification and Dielectrophoretic Trapping for Analyses of Suspended Cancer Cells. MICROMACHINES 2019; 11:mi11010047. [PMID: 31905986 PMCID: PMC7019789 DOI: 10.3390/mi11010047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 12/25/2019] [Accepted: 12/26/2019] [Indexed: 12/12/2022]
Abstract
Microfluidic devices employing dielectrophoresis (DEP) have been widely studied and applied in the manipulation and analysis of single cells. However, several pre-processing steps, such as the preparation of purified target samples and buffer exchanges, are necessary to utilize DEP forces for suspended cell samples. In this paper, a sequential cell-processing device, which is composed of pre-processing modules that employ deterministic lateral displacement (DLD) and a single-cell trapping device employing an electroactive microwell array (EMA), is proposed to perform the medium exchange followed by arraying single cells sequentially using DEP. Two original microfluidic devices were efficiently integrated by using the interconnecting substrate containing rubber gaskets that tightly connect the inlet and outlet of each device. Prostate cancer cells (PC3) suspended in phosphate-buffered saline buffer mixed with microbeads were separated and then resuspended into the DEP buffer in the integrated system. Thereafter, purified PC3 cells were trapped in a microwell array by using the positive DEP force. The achieved separation and trapping efficiencies exceeded 94% and 93%, respectively, when using the integrated processing system. This study demonstrates an integrated microfluidic device by processing suspended cell samples, without the requirement of complex preparation steps.
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Tada S, Omi Y, Eguchi M. Analysis of the dielectrophoretic properties of cells using the isomotive AC electric field. BIOMICROFLUIDICS 2018; 12:044103. [PMID: 30034566 PMCID: PMC6035052 DOI: 10.1063/1.5031054] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/06/2018] [Indexed: 06/08/2023]
Abstract
Various microfluidic devices utilizing the principle of dielectrophoresis (DEP) have been developed to separate, concentrate, and characterize biological cells; however, their performance is still limited by a lack of quantitative characterization. We addressed this limitation by employing a method capable of accurately quantifying a cell's response to an imposed field gradient. In this study, a simple method using a newly designed Creek-gap electrode was proposed, and the electrokinetic behavior of cells was characterized by DEP velocimetry under the exposure of an approximately constant gradient of electric field square established along the gap of the electrodes. Together with the numerical prediction of the electric field based on three-dimensional electric field analysis, the magnitude of DEP forces and the real part of the Clausius-Mossotti factor of cells were deduced from their movement. Results demonstrated that the proposed method was applicable to the determination of the dielectrophoretic properties of cells.
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Affiliation(s)
- Shigeru Tada
- Department of Applied Physics, National Defense Academy, Yokosuka, Kanagawa 239-8686, Japan
| | - Yui Omi
- Department of Applied Physics, National Defense Academy, Yokosuka, Kanagawa 239-8686, Japan
| | - Masanori Eguchi
- Fuzzy Logic Systems Institute, Iizuka, Fukuoka 820-0067, Japan
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