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Morcelles KF, Bertemes-Filho P. Hardware for cell culture electrical impedance tomography: A critical review. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:104704. [PMID: 34717415 DOI: 10.1063/5.0053707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
Human cell cultures are powerful laboratory tools for biological models of diseases, drug development, and tissue engineering. However, the success of biological experiments often depends on real-time monitoring of the culture state. Conventional culture evaluation methods consist of end-point laborious techniques, not capable of real-time operation and not suitable for three-dimensional cultures. Electrical Impedance Tomography (EIT) is a non-invasive imaging technique with high potential to be used in cell culture monitoring due to its biocompatibility, non-invasiveness, high temporal resolution, compact hardware, automatic operation, and high throughput. This review approaches the different hardware strategies for cell culture EIT that are presented in the literature, discussing the main components of the measurement system: excitation circuit, voltage/current sensing, switching stage, signal specifications, electrode configurations, measurement protocols, and calibration strategies. The different approaches are qualitatively discussed and compared, and design guidelines are proposed.
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Affiliation(s)
- K F Morcelles
- Department of Electrical Engineering, Santa Catarina State University, Joinville 89219-710, Brazil
| | - P Bertemes-Filho
- Department of Electrical Engineering, Santa Catarina State University, Joinville 89219-710, Brazil
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2
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Kassanos P, Seichepine F, Yang GZ. A Comparison of Front-End Amplifiers for Tetrapolar Bioimpedance Measurements. IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 2021; 70:1-14. [PMID: 0 DOI: 10.1109/tim.2020.3015605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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3
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Park M, Eom K, Jung MH, Park YS, Lee JY, Nam SH. Design of Bio-Impedance Electrode Topologies for Specific Depth Sensing in Skin Layer. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3961-3964. [PMID: 33018867 DOI: 10.1109/embc44109.2020.9175336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Bio-impedance analysis provides non-invasive estimation of body composition. Recently, applications based on bio-impedance measurement in skin tissue such as skin cancer diagnosis and skin composition monitoring have been studied. For scanning the electrical properties along the skin depth, the relationship between the electrode topologies and the depth sensitivity should be clarified. This work reports a systematic analysis on designing line electrode topologies to measure the bio-impedance of the skin layer at specific depth using a finite element method (FEM). Four electrodes consisting of two outer current electrodes and two inner voltage electrodes in the form of Wenner-Schlumberger array were employed on the top of a collagen layer as a skin model. The numerical results demonstrate a change in the effective depth of measurement depending on the electrode topologies, which also have a good agreement with an analytic solution. This study suggests a decision guideline for designing the electrode topologies to achieve target depth sensitivity in bio-impedance measurement of skin tissue.Clinical Relevance-This establishes the effect of electrode topologies on depth sensitivity in bio-impedance measurements in skin layer.
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Gatabi ZR, Mohammadpour R, Gatabi JR, Mirhoseini M, Ahmadi M, Sasanpour P. Sandblasting improves the performance of electrodes of miniature electrical impedance tomography via double layer capacitance. Heliyon 2020; 6:e03652. [PMID: 32258511 PMCID: PMC7118304 DOI: 10.1016/j.heliyon.2020.e03652] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/27/2020] [Accepted: 03/20/2020] [Indexed: 11/01/2022] Open
Abstract
Effect of sandblasting of the copper electrode structures before deposition of gold thin film for micro electrical impedance tomography (EIT) system has been studied experimentally. The comparison has been performed on the unmodified copper electrodes and the sandblasted electrodes before deposition of gold layer, using structural analysis while their performance in EIT system has been measured and analyzed. The results of scanning electron microscopy and atomic force microscopy show that the sandblasting of the electrodes results in the deposition of gold film with smaller grain size and uniformly, comparing to the unmodified structure. The measurement of impedance shows that the sandblasting will increase the double layer capacitance of electrode structure which improves the impedance measurement accordingly.
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Affiliation(s)
- Zahra Rezanejad Gatabi
- Department of Biomedical Engineering and Medical Physics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Raheleh Mohammadpour
- Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran, Iran
| | | | - Mehri Mirhoseini
- Amol Faculty of Paramedical Sciences, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mohsen Ahmadi
- Department of Biomedical Engineering and Medical Physics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Pezhman Sasanpour
- Department of Biomedical Engineering and Medical Physics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,School of Nanoscience, Institute for Research in Fundamental Sciences (IPM), P. O. Box 19395-5531, Tehran, Iran
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5
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Bal-Öztürk A, Miccoli B, Avci-Adali M, Mogtader F, Sharifi F, Çeçen B, Yaşayan G, Braeken D, Alarcin E. Current Strategies and Future Perspectives of Skin-on-a-Chip Platforms: Innovations, Technical Challenges and Commercial Outlook. Curr Pharm Des 2019; 24:5437-5457. [PMID: 30727878 DOI: 10.2174/1381612825666190206195304] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 02/02/2019] [Indexed: 01/09/2023]
Abstract
The skin is the largest and most exposed organ in the human body. Not only it is involved in numerous biological processes essential for life but also it represents a significant endpoint for the application of pharmaceuticals. The area of in vitro skin tissue engineering has been progressing extensively in recent years. Advanced in vitro human skin models strongly impact the discovery of new drugs thanks to the enhanced screening efficiency and reliability. Nowadays, animal models are largely employed at the preclinical stage of new pharmaceutical compounds development for both risk assessment evaluation and pharmacokinetic studies. On the other hand, animal models often insufficiently foresee the human reaction due to the variations in skin immunity and physiology. Skin-on-chips devices offer innovative and state-of-the-art platforms essential to overcome these limitations. In the present review, we focus on the contribution of skin-on-chip platforms in fundamental research and applied medical research. In addition, we also highlighted the technical and practical difficulties that must be overcome to enhance skin-on-chip platforms, e.g. embedding electrical measurements, for improved modeling of human diseases as well as of new drug discovery and development.
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Affiliation(s)
- Ayça Bal-Öztürk
- Department of Analytical Chemistry, Faculty of Pharmacy, İstinye University, 34010, Zeytinburnu, Istanbul, Turkey,Department of Stem Cell and Tissue Engineering, Institute of Health Sciences, Istinye University, 34010 Istanbul, Turkey
| | - Beatrice Miccoli
- Imec, Department of Life Sciences and Imaging, 3001 Heverlee, Belgium,Katholieke Universiteit Leuven, 3000 Leuven, Belgium
| | - Meltem Avci-Adali
- Department of Thoracic and Cardiovascular Surgery, University Hospital Tuebingen, Calwerstraße 7/1, 72076 Tuebingen, Germany
| | - Ferzaneh Mogtader
- Department of Stem Cell and Tissue Engineering, Institute of Health Sciences, Istinye University, 34010 Istanbul, Turkey,NanoBMT, Cyberpark, Bilkent 06800, Ankara, Turkey
| | - Fatemeh Sharifi
- Department of Mechanical Engineering, Sharif University of Technology, Tehran 11365-11155, Iran
| | - Berivan Çeçen
- Biomechanics Department, Institute of Health Science, Dokuz Eylul University, 35340, Inciraltı, Izmir, Turkey; Department of Pharmaceutical Technology, Faculty of Pharmacy, Marmara University, Istanbul, Turkey
| | - Gökçen Yaşayan
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Marmara University, 34668, Haydarpaşa, Istanbul, Turkey
| | - Dries Braeken
- Imec, Department of Life Sciences and Imaging, 3001 Heverlee, Belgium
| | - Emine Alarcin
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Marmara University, 34668, Haydarpaşa, Istanbul, Turkey
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Schwarz M, Jendrusch M, Constantinou I. Spatially resolved electrical impedance methods for cell and particle characterization. Electrophoresis 2019; 41:65-80. [PMID: 31663624 DOI: 10.1002/elps.201900286] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/25/2019] [Accepted: 10/25/2019] [Indexed: 12/24/2022]
Abstract
Electrical impedance is an established technique used for cell and particle characterization. The temporal and spectral resolution of electrical impedance have been used to resolve basic cell characteristics like size and type, as well as to determine cell viability and activity. Such electrical impedance measurements are typically performed across the entire sample volume and can only provide an overall indication concerning the properties and state of that sample. For the study of heterogeneous structures such as cell layers, biological tissue, or polydisperse particle mixtures, an overall measured impedance value can only provide limited information and can lead to data misinterpretation. For the investigation of localized sample properties in complex heterogeneous structures/mixtures, the addition of spatial resolution to impedance measurements is necessary. Several spatially resolved impedance measurement techniques have been developed and applied to cell and particle research, including electrical impedance tomography, scanning electrochemical microscopy, and microelectrode arrays. This review provides an overview of spatially resolved impedance measurement methods and assesses their applicability for cell and particle characterization.
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Affiliation(s)
- Marvin Schwarz
- Institute of Microtechnology, Technische Universität Braunschweig, Braunschweig, Germany.,Center of Pharmaceutical Engineering (PVZ), Technische Universität Braunschweig, Braunschweig, Germany
| | | | - Iordania Constantinou
- Institute of Microtechnology, Technische Universität Braunschweig, Braunschweig, Germany.,Center of Pharmaceutical Engineering (PVZ), Technische Universität Braunschweig, Braunschweig, Germany
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Gamal W, Wu H, Underwood I, Jia J, Smith S, Bagnaninchi PO. Impedance-based cellular assays for regenerative medicine. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0226. [PMID: 29786561 DOI: 10.1098/rstb.2017.0226] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2018] [Indexed: 12/22/2022] Open
Abstract
Therapies based on regenerative techniques have the potential to radically improve healthcare in the coming years. As a result, there is an emerging need for non-destructive and label-free technologies to assess the quality of engineered tissues and cell-based products prior to their use in the clinic. In parallel, the emerging regenerative medicine industry that aims to produce stem cells and their progeny on a large scale will benefit from moving away from existing destructive biochemical assays towards data-driven automation and control at the industrial scale. Impedance-based cellular assays (IBCA) have emerged as an alternative approach to study stem-cell properties and cumulative studies, reviewed here, have shown their potential to monitor stem-cell renewal, differentiation and maturation. They offer a novel method to non-destructively assess and quality-control stem-cell cultures. In addition, when combined with in vitro disease models they provide complementary insights as label-free phenotypic assays. IBCA provide quantitative and very sensitive results that can easily be automated and up-scaled in multi-well format. When facing the emerging challenge of real-time monitoring of three-dimensional cell culture dielectric spectroscopy and electrical impedance tomography represent viable alternatives to two-dimensional impedance sensing.This article is part of the theme issue 'Designer human tissue: coming to a lab near you'.
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Affiliation(s)
- W Gamal
- School of Electronic Engineering, Bangor University, Bangor LL57 1UT, UK
| | - H Wu
- School of Engineering, University of Edinburgh, Edinburgh EH9 3FB, UK
| | - I Underwood
- School of Engineering, University of Edinburgh, Edinburgh EH9 3FB, UK
| | - J Jia
- School of Engineering, University of Edinburgh, Edinburgh EH9 3FB, UK
| | - S Smith
- School of Engineering, University of Edinburgh, Edinburgh EH9 3FB, UK
| | - P O Bagnaninchi
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK
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Wu H, Zhou W, Yang Y, Jia J, Bagnaninchi P. Exploring the Potential of Electrical Impedance Tomography for Tissue Engineering Applications. MATERIALS 2018; 11:ma11060930. [PMID: 29857521 PMCID: PMC6025244 DOI: 10.3390/ma11060930] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 05/24/2018] [Accepted: 05/29/2018] [Indexed: 12/17/2022]
Abstract
In tissue engineering, cells are generally cultured in biomaterials to generate three-dimensional artificial tissues to repair or replace damaged parts and re-establish normal functions of the body. Characterizing cell growth and viability in these bioscaffolds is challenging, and is currently achieved by destructive end-point biological assays. In this study, we explore the potential to use electrical impedance tomography (EIT) as a label-free and non-destructive technology to assess cell growth and viability. The key challenge in the tissue engineering application is to detect the small change of conductivity associated with sparse cell distributions in regards to the size of the hosting scaffold, i.e., low volume fraction, until they assemble into a larger tissue-like structure. We show proof-of-principle data, measure cells within both a hydrogel and a microporous scaffold with an ad-hoc EIT equipment, and introduce the frequency difference technique to improve the reconstruction.
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Affiliation(s)
- Hancong Wu
- Agile Tomography Group, School of Engineering, The University of Edinburgh, Edinburgh EH9 3JL, UK; (H.W.).
| | - Wenli Zhou
- Department of Medical Oncology, Changzheng Hospital, Navy Medical University, Shanghai 200070, China.
| | - Yunjie Yang
- Agile Tomography Group, School of Engineering, The University of Edinburgh, Edinburgh EH9 3JL, UK; (H.W.).
| | - Jiabin Jia
- Agile Tomography Group, School of Engineering, The University of Edinburgh, Edinburgh EH9 3JL, UK; (H.W.).
| | - Pierre Bagnaninchi
- MRC Centre for Regenerative Medicine, The University of Edinburgh, Edinburgh EH16 4UU, UK.
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Fathi F, Rahbarghazi R, Rashidi MR. Label-free biosensors in the field of stem cell biology. Biosens Bioelectron 2018; 101:188-198. [DOI: 10.1016/j.bios.2017.10.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 10/13/2017] [Indexed: 01/05/2023]
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10
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Amini M, Hisdal J, Kalvøy H. Applications of Bioimpedance Measurement Techniques in Tissue Engineering. JOURNAL OF ELECTRICAL BIOIMPEDANCE 2018; 9:142-158. [PMID: 33584930 PMCID: PMC7852004 DOI: 10.2478/joeb-2018-0019] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Indexed: 05/19/2023]
Abstract
Rapid development in the field of tissue engineering necessitates implementation of monitoring methods for evaluation of the viability and characteristics of the cell cultures in a real-time, non-invasive and non-destructive manner. Current monitoring techniques are mainly histological and require labeling and involve destructive tests to characterize cell cultures. Bioimpedance measurement technique which benefits from measurement of electrical properties of the biological tissues, offers a non-invasive, label-free and real-time solution for monitoring tissue engineered constructs. This review outlines the fundamentals of bioimpedance, as well as electrical properties of the biological tissues, different types of cell culture constructs and possible electrode configuration set ups for performing bioimpedance measurements on these cell cultures. In addition, various bioimpedance measurement techniques and their applications in the field of tissue engineering are discussed.
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Affiliation(s)
- M. Amini
- Department of Physics, University of Oslo, Oslo, Norway
| | - J. Hisdal
- Vascular Investigations and Circulation lab, Aker Hospital, Oslo University Hospital, Oslo, Norway
| | - H. Kalvøy
- Department of Clinical and Biomedical Engineering, Rikshospitalet, Oslo University Hospital, Oslo, Norway
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11
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Liu L, Xiao X, Lei KF, Huang CH. Quantitative impedimetric monitoring of cell migration under the stimulation of cytokine or anti-cancer drug in a microfluidic chip. BIOMICROFLUIDICS 2015; 9:034109. [PMID: 26180566 PMCID: PMC4464059 DOI: 10.1063/1.4922488] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/02/2015] [Indexed: 06/01/2023]
Abstract
Cell migration is a cellular response and results in various biological processes such as cancer metastasis, that is, the primary cause of death for cancer patients. Quantitative investigation of the correlation between cell migration and extracellular stimulation is essential for developing effective therapeutic strategies for controlling invasive cancer cells. The conventional method to determine cell migration rate based on comparison of successive images may not be an objective approach. In this work, a microfluidic chip embedded with measurement electrodes has been developed to quantitatively monitor the cell migration activity based on the impedimetric measurement technique. A no-damage wound was constructed by microfluidic phenomenon and cell migration activity under the stimulation of cytokine and an anti-cancer drug, i.e., interleukin-6 and doxorubicin, were, respectively, investigated. Impedance measurement was concurrently performed during the cell migration process. The impedance change was directly correlated to the cell migration activity; therefore, the migration rate could be calculated. In addition, a good match was found between impedance measurement and conventional imaging analysis. But the impedimetric measurement technique provides an objective and quantitative measurement. Based on our technique, cell migration rates were calculated to be 8.5, 19.1, and 34.9 μm/h under the stimulation of cytokine at concentrations of 0 (control), 5, and 10 ng/ml. This technique has high potential to be developed into a powerful analytical platform for cancer research.
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Affiliation(s)
- Lu Liu
- School of Electronic Information Engineering, Tianjin University , Tianjin, China
| | - Xia Xiao
- School of Electronic Information Engineering, Tianjin University , Tianjin, China
| | | | - Chia-Hao Huang
- Graduate Institute of Medical Mechatronics, Chang Gung University , Taoyuan, Taiwan
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12
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Impedance sensing device enables early detection of pressure ulcers in vivo. Nat Commun 2015; 6:6575. [PMID: 25779688 DOI: 10.1038/ncomms7575] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 02/09/2015] [Indexed: 02/03/2023] Open
Abstract
When pressure is applied to a localized area of the body for an extended time, the resulting loss of blood flow and subsequent reperfusion to the tissue causes cell death and a pressure ulcer develops. Preventing pressure ulcers is challenging because the combination of pressure and time that results in tissue damage varies widely between patients, and the underlying damage is often severe by the time a surface wound becomes visible. Currently, no method exists to detect early tissue damage and enable intervention. Here we demonstrate a flexible, electronic device that non-invasively maps pressure-induced tissue damage, even when such damage cannot be visually observed. Using impedance spectroscopy across flexible electrode arrays in vivo on a rat model, we find that impedance is robustly correlated with tissue health across multiple animals and wound types. Our results demonstrate the feasibility of an automated, non-invasive 'smart bandage' for early detection of pressure ulcers.
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Liu Q, Wu C, Cai H, Hu N, Zhou J, Wang P. Cell-based biosensors and their application in biomedicine. Chem Rev 2014; 114:6423-61. [PMID: 24905074 DOI: 10.1021/cr2003129] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Qingjun Liu
- Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of the Ministry of Education, Department of Biomedical Engineering, Zhejiang University , Hangzhou 310027, China
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Primiceri E, Chiriacò MS, Rinaldi R, Maruccio G. Cell chips as new tools for cell biology--results, perspectives and opportunities. LAB ON A CHIP 2013; 13:3789-802. [PMID: 23912640 DOI: 10.1039/c3lc50550b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Cell culture technologies were initially developed as research tools for studying cell functions, but nowadays they are essential for the biotechnology industry, with rapidly expanding applications requiring more and more advancements with respect to traditional tools. Miniaturization and integration of sensors and microfluidic components with cell culture techniques open the way to the development of cellomics as a new field of research targeting innovative analytic platforms for high-throughput studies. This approach enables advanced cell studies under controllable conditions by providing inexpensive, easy-to-operate devices. Thanks to their numerous advantages cell-chips have become a hotspot in biosensors and bioelectronics fields and have been applied to very different fields. In this review exemplary applications will be discussed, for cell counting and detection, cytotoxicity assays, migration assays and stem cell studies.
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Affiliation(s)
- Elisabetta Primiceri
- CNR Istituto Nanoscienze - NNL and Dipartimento di Matematica e Fisica "Ennio De Giorgi", Università del Salento, Lecce, Italy.
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15
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Bajwa A, Tan ST, Mehta R, Bahreyni B. Rapid detection of viable microorganisms based on a plate count technique using arrayed microelectrodes. SENSORS (BASEL, SWITZERLAND) 2013; 13:8188-98. [PMID: 23803788 PMCID: PMC3758590 DOI: 10.3390/s130708188] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 05/22/2013] [Accepted: 06/06/2013] [Indexed: 12/19/2022]
Abstract
Development of a miniaturized biosensor system that can be used for rapid detection and counting of microorganisms in food or water samples is described. The developed microsystem employs a highly sensitive impedimetric array of biosensors to monitor the growth of bacterial colonies that are dispersed across an agar growth medium. To use the system, a sample containing the bacteria is cultured above the agar layer. Using a multiplexing network, the electrical properties of the medium at different locations are continuously measured, recorded, and compared against a baseline signal. Variations of signals from different biosensors are used to reveal the presence of bacteria in the sample, as well as the locations of bacterial colonies across the biochip. This technique forms the basis for a label-free bacterial detection for rapid analysis of food samples, reducing the detection time by at least a factor of four compared to the current required incubation times of 24 to 72 hours for plate count techniques. The developed microsystem has the potential for miniaturization to a stage where it could be deployed for rapid analysis of food samples at commercial scale at laboratories, food processing facilities, and retailers.
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Affiliation(s)
- Avneet Bajwa
- Alberta Health Services, Calgary, AB T2N 2T9, Canada; E-Mail:
| | - Shaoqing Tim Tan
- School of Mechatronic Systems Engineering, Simon Fraser University, Surrey, BC V3T 0A3, Canada; E-Mail:
| | - Ram Mehta
- PBR Laboratories Inc., Edmonton, AB T6E 0P5, Canada; E-Mail:
| | - Behraad Bahreyni
- School of Mechatronic Systems Engineering, Simon Fraser University, Surrey, BC V3T 0A3, Canada; E-Mail:
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Alexander FA, Price DT, Bhansali S. From Cellular Cultures to Cellular Spheroids: Is Impedance Spectroscopy a Viable Tool for Monitoring Multicellular Spheroid (MCS) Drug Models? IEEE Rev Biomed Eng 2013; 6:63-76. [DOI: 10.1109/rbme.2012.2222023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Ostrovidov S, Sakai Y, Fujii T. Integration of a pump and an electrical sensor into a membrane-based PDMS microbioreactor for cell culture and drug testing. Biomed Microdevices 2012; 13:847-64. [PMID: 21728068 DOI: 10.1007/s10544-011-9555-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To the extent possible, artificial organs should have characteristics that match those of the in vivo system. To this end, microfabrication techniques allow us to create microenvironments that can help maintain cell organization and functionality in in vitro cultures. We present three new microbioreactors, each of which allows cells to be cultured in a perfused microenvironment similar to that found in vivo. Our microbioreactors use new technology that permits integration onto the chip (35 mm × 20 mm) of an electrical sensor, in addition to one or more pumping systems and associated perfusion circuitry. The monitoring of Caco-2 cell cultures using electrical impedance spectroscopy (EIS) has allowed us to measure the effects of cell growth, cellular barrier formation and the presence of chemical compounds and/or toxins. Specifically, we have investigated the ability of the electrical sensor to maintain appropriate sensitivity and precision. Our results show that the sensor was very sensitive not only to the presence or the absence of the cells, but also to changes in cell state. Our perfused microbioreactors are highly efficient miniaturized tools that are easy to operate. We anticipate that they will offer promising new opportunities in many types of cell culture research, including drug screening and tissue engineering.
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Affiliation(s)
- Serge Ostrovidov
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
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18
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Primiceri E, Chiriacò MS, Dioguardi F, Monteduro AG, D'Amone E, Rinaldi R, Giannelli G, Maruccio G. Automatic transwell assay by an EIS cell chip to monitor cell migration. LAB ON A CHIP 2011; 11:4081-6. [PMID: 22012570 DOI: 10.1039/c1lc20540d] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Here an EIS (electrochemical impedance spectroscopy) biochip to detect cell migration is demonstrated. This biochip has been inspired by a traditional transwell assay/modified Boyden chamber and consists of two compartments separated by a porous membrane. This structure (PDMS-based) is aligned to EIS sensors. Cells are seeded in the upper chamber through microfluidic channels. During migration cells go through the pores of the membrane and get in touch with the electrodes that detect migrated cells. The performance of our cell-chip was tested by investigating the migratory ability of hepatocellular carcinoma (HCC) cells as a function of microenvironment. For this purpose we challenged HCC cells to migrate on different extra-cellular matrix (ECM) components including laminin 1, collagen IV and laminin 5. The results reveal that our cell chip provides reliable results that consistently overlap with those obtained with traditional standardized Boyden chambers. Thus, we demonstrate a new, easy tool to study cell migration and to perform automatic assays. This approach is easier and faster than traditional transwell assays and can be suitable for high-throughput studies in drug discovery applications.
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Gou HL, Zhang XB, Bao N, Xu JJ, Xia XH, Chen HY. Label-free electrical discrimination of cells at normal, apoptotic and necrotic status with a microfluidic device. J Chromatogr A 2011; 1218:5725-9. [DOI: 10.1016/j.chroma.2011.06.102] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 06/21/2011] [Accepted: 06/26/2011] [Indexed: 01/12/2023]
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20
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Meissner R, Eker B, Kasi H, Bertsch A, Renaud P. Distinguishing drug-induced minor morphological changes from major cellular damage via label-free impedimetric toxicity screening. LAB ON A CHIP 2011; 11:2352-2361. [PMID: 21647498 DOI: 10.1039/c1lc20212j] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present a novel perfusion-based microfluidic platform for label-free drug toxicity screening which can single out non-lethal morphological changes from cellular death using electrical impedance spectroscopy. Minor cellular changes such as cell-cell contacts and major cell injury were identified via impedance phase angle analysis and follow-up of impedance magnitude at different frequencies. Having exposed HepG2/C3A cells to acetaminophen (AP), we showed that continuous drug perfusion caused a time and concentration-dependent impedance decrease. Moreover, perfusion of repeated doses revealed altered dielectric properties of the cell culture after recovery from AP exposure. This study highlights the possibility to sense cellular changes long before cellular death takes place, pointing out the remarkable sensitivity advantage of this technique over standard endpoint viability tests and its interest for toxicology.
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Affiliation(s)
- Robert Meissner
- Laboratoire de Microsystèmes LMIS4, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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21
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Real-time monitoring of neural differentiation of human mesenchymal stem cells by electric cell-substrate impedance sensing. J Biomed Biotechnol 2011; 2011:485173. [PMID: 21716652 PMCID: PMC3116536 DOI: 10.1155/2011/485173] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 02/23/2011] [Accepted: 04/02/2011] [Indexed: 11/17/2022] Open
Abstract
Stem cells are useful for cell replacement therapy. Stem cell differentiation must be monitored thoroughly and precisely prior to transplantation. In this study we evaluated the usefulness of electric cell-substrate impedance sensing (ECIS) for in vitro real-time monitoring of neural differentiation of human mesenchymal stem cells (hMSCs). We cultured hMSCs in neural
differentiation media (NDM) for 6 days and examined the time-course of impedance changes with an ECIS array. We also
monitored the expression of markers for neural differentiation, total cell count, and cell cycle profiles. Cellular expression of
neuron and oligodendrocyte markers increased. The resistance value of cells cultured in NDM was automatically measured in real-time
and found to increase much more slowly over time compared to cells cultured in non-differentiation media. The relatively slow
resistance changes observed in differentiating MSCs were determined to be due to their lower growth capacity achieved by
induction of cell cycle arrest in G0/G1. Overall results suggest that the relatively slow change in resistance values measured by
ECIS method can be used as a parameter for slowly growing neural-differentiating cells. However, to enhance the competence
of ECIS for in vitro real-time monitoring of neural differentiation of MSCs, more elaborate studies are needed.
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22
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Nasir M, Price DT, Shriver-Lake LC, Ligler F. Effect of diffusion on impedance measurements in a hydrodynamic flow focusing sensor. LAB ON A CHIP 2010; 10:2787-2795. [PMID: 20725680 DOI: 10.1039/c005257d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This paper investigated the effects of diffusion between non-conductive sheath and conductive sample fluids in an impedance-based biosensor. Impedance measurements were made with 2- and 4-electrode configurations. The 4-electrode design offers the advantage of impedance measurements at low frequencies (<1 kHz) without the deleterious effects of double layer impedance which are present in the 2-electrode design. Hydrodynamic flow focusing was achieved with a modified T-junction design with a smaller cross-section for the sample channel than for the focusing channel, which resulted in 2D focusing of the sample stream with just one sheath stream. By choosing a non-conductive sheath fluid and a conductive sample fluid, the electric field was confined to the focused stream. In order to utilize this system for biosensing applications, we characterized it for electrical and flow parameters. In particular, we investigated the effects of varying flow velocities and flow-rate ratios on the focused stream. Increasing flow-rate ratios reduced the cross-sectional area of the focused streams as was verified by finite element modeling and confocal microscopy. Antibody mediated binding of Escherichia coli to the electrode surface caused an increase in solution resistance at low frequencies. The results also showed that the diffusion mass transport at the interface of the two streams limited the benefits of increased flow focusing. Increasing flow velocities could be used to offset the diffusion effect. To optimize detection sensitivity, flow parameters and mass transport must be considered in conjunction, with the goal of reducing diffusion of conducting species out of the focused stream while simultaneously minimizing its cross-sectional area.
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Affiliation(s)
- Mansoor Nasir
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375, USA
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23
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Cheung KC, Di Berardino M, Schade-Kampmann G, Hebeisen M, Pierzchalski A, Bocsi J, Mittag A, Tárnok A. Microfluidic impedance-based flow cytometry. Cytometry A 2010; 77:648-66. [PMID: 20583276 DOI: 10.1002/cyto.a.20910] [Citation(s) in RCA: 164] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Microfabricated flow cytometers can detect, count, and analyze cells or particles using microfluidics and electronics to give impedance-based characterization. Such systems are being developed to provide simple, low-cost, label-free, and portable solutions for cell analysis. Recent work using microfabricated systems has demonstrated the capability to analyze micro-organisms, erythrocytes, leukocytes, and animal and human cell lines. Multifrequency impedance measurements can give multiparametric, high-content data that can be used to distinguish cell types. New combinations of microfluidic sample handling design and microscale flow phenomena have been used to focus and position cells within the channel for improved sensitivity. Robust designs will enable focusing at high flowrates while reducing requirements for control over multiple sample and sheath flows. Although microfluidic impedance-based flow cytometers have not yet or may never reach the extremely high throughput of conventional flow cytometers, the advantages of portability, simplicity, and ability to analyze single cells in small populations are, nevertheless, where chip-based cytometry can make a large impact.
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Affiliation(s)
- Karen C Cheung
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, Canada.
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24
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Malleo D, Nevill JT, Lee LP, Morgan H. Continuous differential impedance spectroscopy of single cells. MICROFLUIDICS AND NANOFLUIDICS 2010; 9:191-198. [PMID: 20927185 PMCID: PMC2944380 DOI: 10.1007/s10404-009-0534-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 11/11/2009] [Indexed: 05/21/2023]
Abstract
A device for continuous differential impedance analysis of single cells held by a hydrodynamic cell trapping is presented. Measurements are accomplished by recording the current from two closely-situated electrode pairs, one empty (reference) and one containing a cell. We demonstrate time-dependent measurement of single cell impedance produced in response to dynamic chemical perturbations. First, the system is used to assay the response of HeLa cells to the effects of the surfactant Tween, which reduces the impedance of the trapped cells in a concentration dependent way and is interpreted as gradual lysis of the cell membrane. Second, the effects of the bacterial pore-forming toxin, Streptolysin-O are measured: a transient exponential decay in the impedance is recorded as the cell membrane becomes increasingly permeable. The decay time constant is inversely proportional to toxin concentration (482, 150, and 30 s for 0.1, 1, and 10 kU/ml, respectively). ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10404-009-0534-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniele Malleo
- School of Electronics and Computer Science, University of Southampton, Southampton, SO17 1BJ UK
- Oxford Gene Technology, Begbroke Science Park, Oxford, OX5 1PF UK
| | - J. Tanner Nevill
- Department of Bioengineering, Biomolecular Nanotechnology Center, Berkeley Sensor and Actuator Center, University of California, Berkeley, CA 94720 USA
- Present Address: Fluxion Biosciences, South San Francisco, CA 94080 USA
| | - Luke P. Lee
- Department of Bioengineering, Biomolecular Nanotechnology Center, Berkeley Sensor and Actuator Center, University of California, Berkeley, CA 94720 USA
| | - Hywel Morgan
- School of Electronics and Computer Science, University of Southampton, Southampton, SO17 1BJ UK
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25
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Frampton JP, Hynd MR, Vargun A, Roysam B, Shain W. An in vitro system for modeling brain reactive responses and changes in neuroprosthetic device impedance. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2010; 2009:7155-8. [PMID: 19965268 DOI: 10.1109/iembs.2009.5335352] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Currently available methods for analyzing the structural properties of neural tissue are limited by the frequency at which data can be collected and by the need to sacrifice the specimen to correlate histology with other data. Electrical impedance spectroscopy (EIS) can be used to complement conventional histological and imaging-based methods by measuring real-time electrical data that can be ascribed to changes in tissue composition and structure. This report describes an impedance-based method for the analysis and modeling of the electrical properties of three-dimensional neural tissue constructs in vitro. This model system was used to assess the effects of cell density, type and organization on neuroprosthetic device electrode performance.
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Affiliation(s)
- John P Frampton
- Department of Biomedical Sciences at the School of Public Health, State University of New York at Albany, Albany, NY 12222, USA. jf7674@ albany.edu
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26
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Hildebrandt C, Büth H, Cho S, Thielecke H. Detection of the osteogenic differentiation of mesenchymal stem cells in 2D and 3D cultures by electrochemical impedance spectroscopy. J Biotechnol 2010; 148:83-90. [PMID: 20085793 DOI: 10.1016/j.jbiotec.2010.01.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 12/18/2009] [Accepted: 01/12/2010] [Indexed: 11/18/2022]
Abstract
Human mesenchymal stem cells are promising candidates for cell-based therapies since they have the capacity to differentiate into a variety of cell types. However, the acceptance of hMSCs for clinical applications as well as in vitro tissue models will depend on strategies for standard characterisations. Impedance spectroscopy is a proven and powerful tool for non-invasive monitoring of cellular processes. The aim of this study was to prove the hypothesis, that the process of osteogenic differentiation can be monitored non-invasively and time-continuously by using impedance spectroscopy. This hypothesis was examined for 2D cell layers of hMSCs by continuous impedance spectroscopy employing a planar electrode-based chip and for 3D aggregates of hMSCs after 21 and 25 days of osteogenic treatment by using a capillary measurement system. The impedance spectra of osteogenic treated hMSCs reported a significant increase of the magnitude of impedance compared to controls cultivated in normal growth medium. The osteogenic status of the cells was determined by alkaline phosphatase expression and von Kossa staining. In respect to that finding it is concluded that impedance spectroscopy is an appropriate method for non-invasive characterisation of osteogenic differentiation of hMSCs, which is relevant for quality control of cell-based implants and cell-based test systems for drug development.
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Affiliation(s)
- Cornelia Hildebrandt
- Department of Biohybrid Systems, Fraunhofer Institute for Biomedical Engineering, Ensheimer Str. 48, 66386 St. Ingbert, Germany
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27
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Jahnke HG, Rothermel A, Sternberger I, Mack TGA, Kurz RG, Pänke O, Striggow F, Robitzki AA. An impedimetric microelectrode-based array sensor for label-free detection of tau hyperphosphorylation in human cells. LAB ON A CHIP 2009; 9:1422-1428. [PMID: 19417909 DOI: 10.1039/b819754g] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tauopathies such as Alzheimer's disease (AD) belong to the group of neurodegenerative diseases that are characterised by hyperphosphorylation of the protein tau. Hyperphosphorylation of tau is one of the salient events leading to neuronal cytotoxicity and cognitive impairments. In this context, inhibition of tau hyperphosphorylation by specific tau kinase inhibitors can provide an excellent drug target for the treatment of AD and other tau-related neurodegenerative diseases. To improve the identification, optimisation and validation during the high-cost hit-to-lead cycle of AD drugs, we established a fast and sensitive label-free technique for testing the efficacy of tau kinase inhibitors in vitro. Here, we report for the first time that microelectrode-based impedance spectroscopy can be used to detect the pathological risk potential of hyperphosphorylated tau in the human neuroblastoma cell line SH-SY5Y. Our findings provide a novel real-time recording technique for testing the efficiency of tau kinase inhibitors or other lead structures directed to tau hyperphosphorylation on differentiated SH-SY5Y cells.
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Affiliation(s)
- Heinz-Georg Jahnke
- Centre for Biotechnology and Biomedicine (BBZ), University of Leipzig, Division of Molecular Biological-Biochemical Processing Technology, Deutscher Platz 5, 04103, Leipzig, Germany
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28
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Rümenapp C, Remm M, Wolf B, Gleich B. Improved method for impedance measurements of mammalian cells. Biosens Bioelectron 2009; 24:2915-9. [PMID: 19321331 DOI: 10.1016/j.bios.2009.02.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 02/04/2009] [Accepted: 02/23/2009] [Indexed: 10/21/2022]
Abstract
This study describes the use of impedance spectroscopy as a non-invasive tool to monitor cell proliferation and morphology and to obtain better measurements of cell kinetics. The goal was to determine test frequencies at which the cell behaviour towards different chemicals and toxins can be monitored with good time resolution. For optimisation of the test frequency it is in the first instance necessary to measure an impedance spectrum of the confluent cell layer. Secondly, the frequency of the highest peak in the spectrum will be determined and further experiments will be carried out at this fixed test frequency. In contrast to measurements at the mainly used 10 kHz (33%), signal differences between a confluent cell layer and cells after treatment with 0.2% Triton X-100 of up to 60% were obtained. In this work the measurements were carried out using interdigitated electrode structures (IDES) on a glass substrate. Impedance spectra of confluent L929 and MDA cell layers were obtained with the Solartron response analyzer.
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Affiliation(s)
- Christine Rümenapp
- Zentralinstitut für Medizintechnik der Technischen Universität München (IMETUM), Boltzmannstrasse 11, 85748 Garching, Germany
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29
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Debuisson D, Treizebré A, Houssin T, Leclerc E, Bartès-Biesel D, Legrand D, Mazurier J, Arscott S, Bocquet B, Senez V. Nanoscale devices for online dielectric spectroscopy of biological cells. Physiol Meas 2008; 29:S213-25. [DOI: 10.1088/0967-3334/29/6/s19] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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30
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Rahman ARA, Register J, Vuppala G, Bhansali S. Cell culture monitoring by impedance mapping using a multielectrode scanning impedance spectroscopy system (CellMap). Physiol Meas 2008; 29:S227-39. [DOI: 10.1088/0967-3334/29/6/s20] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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31
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Bao N, Wang J, Lu C. Recent advances in electric analysis of cells in microfluidic systems. Anal Bioanal Chem 2008; 391:933-42. [DOI: 10.1007/s00216-008-1899-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 01/14/2008] [Accepted: 01/17/2008] [Indexed: 11/24/2022]
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32
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Linderholm P, Marescot L, Loke MH, Renaud P. Cell Culture Imaging Using Microimpedance Tomography. IEEE Trans Biomed Eng 2008; 55:138-46. [DOI: 10.1109/tbme.2007.910649] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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33
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Johnson L, Scribner D, Skeath P, Klein R, Ilg D, Perkins K, Helfgott M, Sanders R, Panigrahi D. Impedance-based retinal contact imaging as an aid for the placement of high resolution epiretinal prostheses. J Neural Eng 2007; 4:S17-23. [PMID: 17325412 DOI: 10.1088/1741-2560/4/1/s03] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
An important factor in effective stimulation of the retina is close contact with the retina. The design of the electrode surface and the placement of the electrode against the retina both affect the degree of contact with the retina. We have addressed the design factor by creating a curved surface 3200-electrode array. The placement factor we have addressed by use of an impedance sensitive feedback from the array. The feedback is in the form of an image showing contact with the retina, where greater pixel intensity indicates greater impedance and thus closer contact with the retina. In this paper, we present qualitative and quantitative assessments of the relationship between impedance and the device output as well as an in vivo demonstration of contact imaging. In addition, we evaluated the three-dimensional profile of the stimulation voltage distribution to assess the importance of close retinal contact for high resolution stimulation.
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Affiliation(s)
- Lee Johnson
- SFA Inc., Onsite Contractor for the Naval Research Laboratory, 4555 Overlook Avenue, Washington, DC 20375, USA.
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