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Saghaei T, Weber A, Reimhult E, van Oostrum PDJ. Distinguishing cells using electro-acoustic spinning. Sci Rep 2023; 13:20466. [PMID: 37993513 PMCID: PMC10665424 DOI: 10.1038/s41598-023-46550-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Accepted: 11/02/2023] [Indexed: 11/24/2023] Open
Abstract
Many diseases, including cancer and covid, result in altered mechanical and electric properties of the affected cells. These changes were proposed as disease markers. Current methods to characterize such changes either provide very limited information on many cells or have extremely low throughput. We introduce electro-acoustic spinning (EAS). Cells were found to spin in combined non-rotating AC electric and acoustic fields. The rotation velocity in EAS depends critically on a cell's electrical and mechanical properties. In contrast to existing methods, the rotation is uniform in the field of view and hundreds of cells can be characterized simultaneously. We demonstrate that EAS can distinguish cells with only minor differences in electric and mechanical properties, including differences in age or the number of passages.
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Affiliation(s)
- Tayebeh Saghaei
- Department of Bionanosciences, Institute of Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11-II, 1190, Vienna, Austria.
| | - Andreas Weber
- Department of Bionanosciences, Institute of Biophysics, University of Natural Resources and Life Sciences, Muthgasse 11-II, 1190, Vienna, Austria
- London Centre for Nanotechnology, Faculty of Maths & Physical Sciences, University College London, Gower Street, London, UK
| | - Erik Reimhult
- Department of Bionanosciences, Institute of Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11-II, 1190, Vienna, Austria
| | - Peter D J van Oostrum
- Department of Bionanosciences, Institute of Biologically Inspired Materials, University of Natural Resources and Life Sciences, Muthgasse 11-II, 1190, Vienna, Austria
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2
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Tian Z, Yuan Z, Duarte PA, Shaheen M, Wang S, Haddon L, Chen J. Highly efficient cell-microbead encapsulation using dielectrophoresis-assisted dual-nanowell array. PNAS NEXUS 2023; 2:pgad155. [PMID: 37252002 PMCID: PMC10210622 DOI: 10.1093/pnasnexus/pgad155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 04/03/2023] [Accepted: 05/03/2023] [Indexed: 05/31/2023]
Abstract
Recent advancements in micro/nanofabrication techniques have led to the development of portable devices for high-throughput single-cell analysis through the isolation of individual target cells, which are then paired with functionalized microbeads. Compared with commercially available benchtop instruments, portable microfluidic devices can be more widely and cost-effectively adopted in single-cell transcriptome and proteome analysis. The sample utilization and cell pairing rate (∼33%) of current stochastic-based cell-bead pairing approaches are fundamentally limited by Poisson statistics. Despite versatile technologies having been proposed to reduce randomness during the cell-bead pairing process in order to statistically beat the Poisson limit, improvement of the overall pairing rate of a single cell to a single bead is typically based on increased operational complexity and extra instability. In this article, we present a dielectrophoresis (DEP)-assisted dual-nanowell array (ddNA) device, which employs an innovative microstructure design and operating process that decouples the bead- and cell-loading processes. Our ddNA design contains thousands of subnanoliter microwell pairs specifically tailored to fit both beads and cells. Interdigitated electrodes (IDEs) are placed below the microwell structure to introduce a DEP force on cells, yielding high single-cell capture and pairing rates. Experimental results with human embryonic kidney cells confirmed the suitability and reproducibility of our design. We achieved a single-bead capture rate of >97% and a cell-bead pairing rate of >75%. We anticipate that our device will enhance the application of single-cell analysis in practical clinical use and academic research.
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Affiliation(s)
- Zuyuan Tian
- Department of Electrical and Computer Engineering, University of Alberta, 9107 116 Street NW, T6G 1H9 Edmonton, AB, Canada
| | - Zhipeng Yuan
- Department of Electrical and Computer Engineering, University of Alberta, 9107 116 Street NW, T6G 1H9 Edmonton, AB, Canada
| | - Pedro A Duarte
- Department of Electrical and Computer Engineering, University of Alberta, 9107 116 Street NW, T6G 1H9 Edmonton, AB, Canada
| | - Mohamed Shaheen
- Department of Electrical and Computer Engineering, University of Alberta, 9107 116 Street NW, T6G 1H9 Edmonton, AB, Canada
| | - Shaoxi Wang
- School of Microelectronics, Northwestern Polytechnical University, 127 Youyi St West, 710129 Xi’an, Shannxi, China
| | - Lacey Haddon
- Department of Electrical and Computer Engineering, University of Alberta, 9107 116 Street NW, T6G 1H9 Edmonton, AB, Canada
| | - Jie Chen
- To whom correspondence should be addressed:
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3
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Mohammadi R, Afsaneh H, Rezaei B, Moghimi Zand M. On-chip dielectrophoretic device for cancer cell manipulation: A numerical and artificial neural network study. BIOMICROFLUIDICS 2023; 17:024102. [PMID: 36896355 PMCID: PMC9991445 DOI: 10.1063/5.0131806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Breast cancer, as one of the most frequent types of cancer in women, imposes large financial and human losses annually. MCF-7, a well-known cell line isolated from the breast tissue of cancer patients, is usually used in breast cancer research. Microfluidics is a newly established technique that provides many benefits, such as sample volume reduction, high-resolution operations, and multiple parallel analyses for various cell studies. This numerical study presents a novel microfluidic chip for the separation of MCF-7 cells from other blood cells, considering the effect of dielectrophoretic force. An artificial neural network, a novel tool for pattern recognition and data prediction, is implemented in this research. To prevent hyperthermia in cells, the temperature should not exceed 35 °C. In the first part, the effect of flow rate and applied voltage on the separation time, focusing efficiency, and maximum temperature of the field is investigated. The results denote that the separation time is affected by both the input parameters inversely, whereas the two remaining parameters increase with the input voltage and decrease with the sheath flow rate. A maximum focusing efficiency of 81% is achieved with a purity of 100% for a flow rate of 0.2 μ L / min and a voltage of 3.1 V . In the second part, an artificial neural network model is established to predict the maximum temperature inside the separation microchannel with a relative error of less than 3% for a wide range of input parameters. Therefore, the suggested label-free lab-on-a-chip device separates the target cells with high-throughput and low voltages.
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Affiliation(s)
- Rasool Mohammadi
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran 11155-463, Iran
| | - Hadi Afsaneh
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Behnam Rezaei
- Small Medical Devices, BioMEMS, and LoC Lab, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran 11155-463, Iran
| | - Mahdi Moghimi Zand
- Small Medical Devices, BioMEMS, and LoC Lab, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran 11155-463, Iran
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4
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Zhang S, Xu B, Elsayed M, Nan F, Liang W, Valley JK, Liu L, Huang Q, Wu MC, Wheeler AR. Optoelectronic tweezers: a versatile toolbox for nano-/micro-manipulation. Chem Soc Rev 2022; 51:9203-9242. [DOI: 10.1039/d2cs00359g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review covers the fundamentals, recent progress and state-of-the-art applications of optoelectronic tweezers technology, and demonstrates that optoelectronic tweezers technology is a versatile and powerful toolbox for nano-/micro-manipulation.
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Affiliation(s)
- Shuailong Zhang
- School of Mechatronical Engineering, Beijing Institute of Technology, Room 711, Building No 6, Science and Technology Park, 5 Zhongguancun South St, Haidian District, Beijing, 100081, China
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing, 100081, China
- Key Laboratory of Biomimetic Robots and Systems (Beijing Institute of Technology), Ministry of Education, Beijing 100081, China
| | - Bingrui Xu
- School of Mechatronical Engineering, Beijing Institute of Technology, Room 711, Building No 6, Science and Technology Park, 5 Zhongguancun South St, Haidian District, Beijing, 100081, China
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing, 100081, China
| | - Mohamed Elsayed
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, M5S 3G9, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, M5S 3E1, Canada
| | - Fan Nan
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Wenfeng Liang
- School of Mechanical Engineering, Shenyang Jianzhu University, Shenyang, 110168, China
| | - Justin K. Valley
- Berkeley Lights, Inc, 5858 Horton Street #320, Emeryville, CA 94608, USA
| | - Lianqing Liu
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China
- Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110016, China
| | - Qiang Huang
- School of Mechatronical Engineering, Beijing Institute of Technology, Room 711, Building No 6, Science and Technology Park, 5 Zhongguancun South St, Haidian District, Beijing, 100081, China
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing, 100081, China
- Key Laboratory of Biomimetic Robots and Systems (Beijing Institute of Technology), Ministry of Education, Beijing 100081, China
| | - Ming C. Wu
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
| | - Aaron R. Wheeler
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, M5S 3G9, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, M5S 3E1, Canada
- Department of Chemistry, University of Toronto, Toronto, ON, M5S 3H6, Canada
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5
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Jiang M, Wang X, Zhao X, Teng Y, Chen J, Wang J, Yue W. Classification of tumor subtypes leveraging constriction-channel based impedance flow cytometry and optical imaging. Cytometry A 2021; 99:1114-1122. [PMID: 33909347 DOI: 10.1002/cyto.a.24358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/29/2021] [Indexed: 11/06/2022]
Abstract
As label-free biomarkers, electrical properties of single cells have been widely used for cell-type classification and cell-status evaluation. However, as intrinsic bioelectrical markers, previously reported membrane capacitance and cytoplasmic resistance (e.g., specific membrane capacitance Cspecific membrane and cytoplasmic conductivity σcytoplasm ) of tumor subtypes were derived from tens of single cells, lacking statistical significance due to low cell numbers. In this study, tumor subtypes were constructed based on phenotype (treatment with 4-methylumbelliferone) or genotype (knockdown of ROCK1) modifications and then aspirated through a constriction-channel based impedance flow cytometry to characterize single-cell Cspecific membrane and σcytoplasm . Thousands of single tumor cells with phenotype modifications were measured, resulting in significant differences in 1.64 ± 0.43 μF/cm2 vs. 1.55 ± 0.47 μF/cm2 of Cspecific membrane and 0.96 ± 0.37 S/m vs. 1.24 ± 0.47 S/m of σcytoplasm for 95C cells (792 cells of 95C-control vs. 1529 cells of 95C-pheno-mod); 2.56 ± 0.88 μF/cm2 vs. 2.33 ± 0.56 μF/cm2 of Cspecific membrane and 0.83 ± 0.18 S/m vs. 0.93 ± 0.25 S/m of σcytoplasm for H1299 cells (962 cells of H1299-control vs. 637 cells of H1299-pheno-mod). Furthermore, thousands of single tumor cells with genotype modifications were measured, resulting in significant differences in 3.82 ± 0.92 vs. 3.18 ± 0.47 μF/cm2 of Cspecific membrane and 0.47 ± 0.05 vs. 0.52 ± 0.05 S/m of σcytoplasm (1100 cells of A549-control vs. 1100 cells of A549-geno-mod). These results indicate that as intrinsic bioelectrical markers, specific membrane capacitance and cytoplasmic conductivity can be used to classify tumor subtypes.
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Affiliation(s)
- Mei Jiang
- Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Xiaojie Wang
- Department of Human Reproductive Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Xiaoting Zhao
- Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Yu Teng
- Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Jian Chen
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China.,School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Junbo Wang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China.,School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Wentao Yue
- Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
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6
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Choi S, Lee H, Lee S, Park I, Kim YS, Key J, Lee SY, Yang S, Lee SW. A novel automatic segmentation and tracking method to measure cellular dielectrophoretic mobility from individual cell trajectories for high throughput assay. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 195:105662. [PMID: 32712504 DOI: 10.1016/j.cmpb.2020.105662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 07/09/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND OBJECTIVE The dielectrophoresis (DEP) technique is increasingly being recognised as a potentially valuable tool for non-contact manipulation of numerous cells as well as for biological single cell analysis with non-invasive characterisation of a cell's electrical properties. Several studies have attempted to track multiple cells to characterise their cellular DEP mobility. However, they encountered difficulties in simultaneously tracking the movement of a large number of individual cells in a bright-field image sequence because of interference from the background electrode pattern. Consequently, this present study aims to develop an automatic system for imaging-based characterisation of cellular DEP mobility, which enables the simultaneous tracking of several hundred of cells inside a microfluidic device. METHODS The proposed method for segmentation and tracking of cells consists of two main stages: pre-processing and particle centre localisation. In the pre-processing stage, background subtraction and contrast enhancement were performed to distinguish the cell region from the background image. In the particle centre localisation stage, the unmarked cell was automatically detected via graph-cut algorithm-based K-means clustering. RESULTS Our algorithm enabled segmentation and tracking of numerous Michigan Cancer Foundation-7 (MCF-7) cell trajectories while the DEP force was oscillated between positive and negative. The cell tracking accuracy and cell count capability was at least 90% of the total number of cells with the newly developed algorithm. In addition, the cross-over frequency was measured by analysing the segmented and tracked trajectory data of the cellular movements caused by the positive and negative DEP force. The measured cross-over frequency was compared with previous results. The multi-cellular movements investigation based on the measured cross-over frequency was repeated until the viability of cells was unchanged in the same environment as in a microfluidic device. The results were statistically consistent, indicating that the developed algorithm was reliable for the investigation of DEP cellular mobility. CONCLUSION This study developed a powerful platform to simultaneously measure the DEP-induced trajectories of numerous cells, and to investigate in a robust, efficient, and accurate manner the DEP properties at both the single cell and cell ensemble level.
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Affiliation(s)
- Seungyeop Choi
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Hyunwoo Lee
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Sena Lee
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Insu Park
- Holonyak Micro and Nanotechnology Laboratory, University of Illinois, Urbana, IL, USA
| | - Yoon Suk Kim
- Department of Biomedical Laboratory Science, Yonsei University, Wonju 26493, Republic of Korea
| | - Jaehong Key
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Sei Young Lee
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Sejung Yang
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea.
| | - Sang Woo Lee
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea.
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7
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Elucidating the mechanism governing cell rotation under DEP using the volumetric polarization and integration method. Biomed Microdevices 2018; 20:81. [PMID: 30196336 DOI: 10.1007/s10544-018-0327-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cell rotation can be achieved by utilizing rotating electric fields through which torques are generated due to phase difference between the dipole moment of cells and the external electric field. While reports of cell rotation under non-rotating electrical fields, such as dielectrophoresis (DEP), are abound, the underlying mechanism is not fully understood. Because of this, contradicting arguments remain regarding if a single cell can rotate under conventional DEP. What's more, the current prevailing DEP theory is not adequate for identifying the cause for such disagreements. In this work we applied our recently developed Volumetric Polarization and Integration (VPI) method to investigate the possible causes for cell rotation under conventional DEP. Three-dimensional (3D) computer models dealing with a cell in a DEP environment were developed to quantify the force and torque imparted on the cell by the external DEP field using COMSOL Multiphysics software. Modeling results suggest that eccentric inclusions with low conductivity inside the cell will generate torques (either in clockwise or counter-clockwise directions) sufficient to cause cell rotation under DEP. For validation of modeling predictions, experiments with rat adipose stem cells containing large lipid droplets were conducted. Good agreement between our modeling and experimental results suggests that the VPI method is powerful in elucidating the underlying mechanisms governing the complicated DEP phenomena.
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8
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Vaillier C, Honegger T, Kermarrec F, Gidrol X, Peyrade D. Label-Free Electric Monitoring of Human Cancer Cells as a Potential Diagnostic Tool. Anal Chem 2016; 88:9022-8. [DOI: 10.1021/acs.analchem.6b01648] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Clarisse Vaillier
- Université Grenoble Alpes, F-38000 Grenoble, France
- CNRS, LTM, F-38000 Grenoble, France
| | - Thibault Honegger
- Université Grenoble Alpes, F-38000 Grenoble, France
- CNRS, LTM, F-38000 Grenoble, France
| | - Frédérique Kermarrec
- Université Grenoble Alpes, F-38000 Grenoble, France
- CEA, iRTSV,
Biologie
à Grande Echelle, F-38054 Grenoble, France
- INSERM, U1038, F-38054 Grenoble, France
| | - Xavier Gidrol
- Université Grenoble Alpes, F-38000 Grenoble, France
- CEA, iRTSV,
Biologie
à Grande Echelle, F-38054 Grenoble, France
- INSERM, U1038, F-38054 Grenoble, France
| | - David Peyrade
- Université Grenoble Alpes, F-38000 Grenoble, France
- CNRS, LTM, F-38000 Grenoble, France
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9
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Walid Rezanoor M, Dutta P. Combined AC electroosmosis and dielectrophoresis for controlled rotation of microparticles. BIOMICROFLUIDICS 2016; 10:024101. [PMID: 27014394 PMCID: PMC4788602 DOI: 10.1063/1.4943032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/18/2016] [Indexed: 05/10/2023]
Abstract
Electrorotation is widely used for characterization of biological cells and materials using a rotating electric field. Generally, multiphase AC electric fields and quadrupolar electrode configuration are needed to create a rotating electric field for electrorotation. In this study, we demonstrate a simple method to rotate dielectrophoretically trapped microparticles using a stationary AC electric field. Coplanar interdigitated electrodes are used to create a linearly polarized nonuniform AC electric field. This nonuniform electric field is employed for dielectrophoretic trapping of microparticles as well as for generating electroosmotic flow in the vicinity of the electrodes resulting in rotation of microparticles in a microfluidic device. The rotation of barium titanate microparticles is observed in 2-propanol and methanol solvent at a frequency below 1 kHz. A particle rotation rate as high as 240 revolutions per minute is observed. It is demonstrated that precise manipulation (both rotation rate and equilibrium position) of the particles is possible by controlling the frequency of the applied electric field. At low frequency range, the equilibrium positions of the microparticles are observed between the electrode edge and electrode center. This method of particle manipulation is different from electrorotation as it uses induced AC electroosmosis instead of electric torque as in the case of electrorotation. Moreover, it has been shown that a microparticle can be rotated along its own axis without any translational motion.
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Affiliation(s)
- Md Walid Rezanoor
- School of Mechanical and Materials Engineering, Washington State University , Pullman, Washington 99164-2920, USA
| | - Prashanta Dutta
- School of Mechanical and Materials Engineering, Washington State University , Pullman, Washington 99164-2920, USA
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10
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Vaillier C, Honegger T, Kermarrec F, Gidrol X, Peyrade D. Involvement of membrane proteins and ion channels on the self-rotation of human cells in a non-rotating AC electric field. Electrophoresis 2015; 36:1123-9. [PMID: 25808576 DOI: 10.1002/elps.201400478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 02/27/2014] [Accepted: 03/17/2015] [Indexed: 11/05/2022]
Abstract
Dielectrophoresis is a force that has been exploited in microsystems for label-free characterization and separation of cells, when their electrical signature is known. However, the polarization effect of cells at the transmembrane protein level is not well established. In this work, we have use the self-rotation effect of cells in a non-rotating field, known as the "Quincke effect," in order to measure the maximum rotation frequency (frotmax ) of different cell populations when modifying the composition of their membrane. We investigated the influence of active ionic transportation of membrane protein concentration on frotmax of HEK cells. Our results show that ionic transportation is responsible for the reduction of conductivity within the cytoplasm, which results in higher frotmax . However, the influence of the concentration of proteins in the membrane, achieved by silencing gene expression in cancer cells, changes significantly frotmax , which is not explained by the changes of ionic conductivity within the cell.
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Affiliation(s)
- Clarisse Vaillier
- Univ. Grenoble Alpes, LTM, Grenoble, France.,LTM, CNRS, Grenoble, France
| | - Thibault Honegger
- Univ. Grenoble Alpes, LTM, Grenoble, France.,LTM, CNRS, Grenoble, France
| | - Frédérique Kermarrec
- CEA, Institut de Recherches en Technologies et Sciences pour le Vivant, Grenoble, France
| | - Xavier Gidrol
- CEA, Institut de Recherches en Technologies et Sciences pour le Vivant, Grenoble, France
| | - David Peyrade
- Univ. Grenoble Alpes, LTM, Grenoble, France.,LTM, CNRS, Grenoble, France
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11
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Yan Y, Luo J, Guo D, Wen S. Dynamic dielectrophoresis model of multi-phase ionic fluids. PLoS One 2015; 10:e0117456. [PMID: 25699513 PMCID: PMC4336143 DOI: 10.1371/journal.pone.0117456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 12/24/2014] [Indexed: 11/19/2022] Open
Abstract
Ionic-based dielectrophoretic microchips have attracted significant attention due to their wide-ranging applications in electro kinetic and biological experiments. In this work, a numerical method is used to simulate the dynamic behaviors of ionic droplets in a microchannel under the effect of dielectrophoresis. When a discrete liquid dielectric is encompassed within a continuous fluid dielectric placed in an electric field, an electric force is produced due to the dielectrophoresis effect. If either or both of the fluids are ionic liquids, the magnitude and even the direction of the force will be changed because the net ionic charge induced by an electric field can affect the polarization degree of the dielectrics. However, using a dielectrophoresis model, assuming ideal dielectrics, results in significant errors. To avoid the inaccuracy caused by the model, this work incorporates the electrode kinetic equation and defines a relationship between the polarization charge and the net ionic charge. According to the simulation conditions presented herein, the electric force obtained in this work has an error exceeding 70% of the actual value if the false effect of net ionic charge is not accounted for, which would result in significant issues in the design and optimization of experimental parameters. Therefore, there is a clear motivation for developing a model adapted to ionic liquids to provide precise control for the dielectrophoresis of multi-phase ionic liquids.
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Affiliation(s)
- Ying Yan
- Tsinghua University, State Key Lab of Tribology, Beijing, P. R. China
| | - Jing Luo
- Tsinghua University, State Key Lab of Tribology, Beijing, P. R. China
| | - Dan Guo
- Tsinghua University, State Key Lab of Tribology, Beijing, P. R. China
| | - Shizhu Wen
- Tsinghua University, State Key Lab of Tribology, Beijing, P. R. China
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