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Yoon D, Nam Y. A 3D neuronal network read-out interface with high recording performance using a neuronal cluster patterning on a microelectrode array. Biosens Bioelectron 2024; 261:116507. [PMID: 38905857 DOI: 10.1016/j.bios.2024.116507] [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: 03/21/2024] [Revised: 05/27/2024] [Accepted: 06/15/2024] [Indexed: 06/23/2024]
Abstract
In recent years, in vitro three-dimensional (3D) neuronal network models utilizing extracellular matrices have been advancing. To understand the network activity from these models, attempts have been made to measure activity in multiple regions simultaneously using a microelectrode array (MEA). Although there hve been many attempts to measure the activity of 3D networks using 2-dimensional (2D) MEAs, the physical coupling between the 3D network and the microelectrodes was not stable and needed to be improved. In this study, we proposed a neuronal cluster interface that improves the active channel ratio of commercial 2D MEAs, enabling reliable measurement of 3D network activity. To achieve this, neuronal clusters, which consist of a small number of neurons, were patterned on microelectrodes and used as mediators to transmit the signal between the 3D network and the microelectrodes. We confirmed that the patterned neuronal clusters enhanced the active channel ratio and SNR(signal-to-noise-ratio) about 3D network recording and stimulation for a month. Our interface was able to functionally connect with 3D networks and measure the 3D network activity without significant alternation of activity characteristics. Finally, we demonstrated that our interface can be used to analyze the differences in the dynamics of 3D and 2D networks and to construct the 3D clustered network. This method is expected to be useful for studying the functional activity of various 3D neuronal network models, offering broad applications for the use of these models.
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Affiliation(s)
- Dongjo Yoon
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Yoonkey Nam
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.
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2
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Habibey R, Striebel J, Meinert M, Latiftikhereshki R, Schmieder F, Nasiri R, Latifi S. Engineered modular neuronal networks-on-chip represent structure-function relationship. Biosens Bioelectron 2024; 261:116518. [PMID: 38924816 DOI: 10.1016/j.bios.2024.116518] [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: 02/08/2024] [Revised: 06/18/2024] [Accepted: 06/20/2024] [Indexed: 06/28/2024]
Abstract
Brain function is substantially linked to the highly organized modular structure of neuronal networks. However, the structure of in vitro assembled neuronal circuits often exhibits variability, complicating the consistent recording of network functional output and its correlation to network structure. Therefore, engineering neuronal structures with predefined geometry and reproducible functional features is essential to precisely model in vivo neuronal circuits. Here, we engineered microchannel devices to assemble 2D and 3D modular networks. The microchannel devices were coupled with a multi-electrode array (MEA) electrophysiology system to enable recordings from circuits. Each network consisted of 64 modules connected to their adjacent modules by micron-sized channels. Modular circuits within microchannel devices showed enhanced activity and functional connectivity traits. This includes metrics such as connection weights, clustering coefficient, global efficiency, and the number of hub neurons with higher betweenness centrality. In addition, modular networks demonstrated an increased functional modularity score compared to the randomly formed circuits. Neurons within individual modules displayed uniform network characteristics and predominantly participated in their respective functional communities within the same or neighboring physical modules. These observations highlight that the modular network structure promotes the development of segregated functional connectivity traits while simultaneously enhancing the efficiency of overall network connectivity. Our findings emphasize the significant impact of physical constraints on the activity patterns and functional organization within engineered modular networks. These circuits, characterized by stable modular architecture and intricate functional dynamics-key features of the brain networks-offer a robust in vitro model for advancing neuroscience research.
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Affiliation(s)
- Rouhollah Habibey
- Department of Ophthalmology, Medical Faculty, University of Bonn, Bonn, Germany; CRTD - Center for Regenerative Therapies TU Dresden, 01307, Dresden, Germany; Dept. Neuroscience, Italian Institute of Technology. Genova, Italy.
| | - Johannes Striebel
- Department of Ophthalmology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Melissa Meinert
- Department of Ophthalmology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Roshanak Latiftikhereshki
- Department of Computer Engineering, Faculty of Engineering, Kermanshah Branch, Azad University, Kermanshah, Iran
| | - Felix Schmieder
- Laboratory of Measurement and Sensor System Technique, Faculty of Electrical and Computer Engineering, TU Dresden, Helmholtzstraße 18, 01069, Dresden, Germany
| | - Rohollah Nasiri
- Division of Nanobiotechnology, Department of Protein Science, Science for Life Laboratory, KTH Royal Institute of Technology, Solna, Sweden; AIMES, Center for the Advancement of Integrated Medical and Engineering Sciences, Department of Neuroscience, Karolinska Institute, Solna, Sweden
| | - Shahrzad Latifi
- Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA; Department of Neuroscience, Rockefeller Neuroscience Institute West Virginia University, Morgantown, WV, 26506, USA
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3
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Stoppini L, Heuschkel MO, Loussert-Fonta C, Gomez Baisac L, Roux A. Versatile micro-electrode array to monitor human iPSC derived 3D neural tissues at air-liquid interface. Front Cell Neurosci 2024; 18:1389580. [PMID: 38784710 PMCID: PMC11112036 DOI: 10.3389/fncel.2024.1389580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 04/02/2024] [Indexed: 05/25/2024] Open
Abstract
Engineered 3D neural tissues made of neurons and glial cells derived from human induced pluripotent stem cells (hiPSC) are among the most promising tools in drug discovery and neurotoxicology. They represent a cheaper, faster, and more ethical alternative to in vivo animal testing that will likely close the gap between in vitro animal models and human clinical trials. Micro-Electrode Array (MEA) technology is known to provide an assessment of compound effects on neural 2D cell cultures and acute tissue preparations by real-time, non-invasive, and long-lasting electrophysiological monitoring of spontaneous and evoked neuronal activity. Nevertheless, the use of engineered 3D neural tissues in combination with MEA biochips still involves series of constraints, such as drastically limited diffusion of oxygen and nutrients within tissues mainly due to the lack of vascularization. Therefore, 3D neural tissues are extremely sensitive to experimental conditions and require an adequately designed interface that provides optimal tissue survival conditions. A well-suited technique to overcome this issue is the combination of the Air-Liquid Interface (ALI) tissue culture method with the MEA technology. We have developed a full 3D neural tissue culture process and a data acquisition system composed of high-end electronics and novel MEA biochips based on porous, flexible, thin-film membranes integrating recording electrodes, named as "Strip-MEA," to allow the maintenance of an ALI around the 3D neural tissues. The main motivation of the porous MEA biochips development was the possibility to monitor and to study the electrical activity of 3D neural tissues under different recording configurations, (i) the Strip-MEA can be placed below a tissue, (ii) or by taking advantage of the ALI, be directly placed on top of the tissue, or finally, (iii) it can be embedded into a larger neural tissue generated by the fusion of two (or more) tissues placed on both sides of the Strip-MEA allowing the recording from its inner part. This paper presents the recording and analyses of spontaneous activity from the three positioning configurations of the Strip-MEAs. Obtained results are discussed with the perspective of developing in vitro models of brain diseases and/or impairment of neural network functioning.
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Affiliation(s)
| | | | | | | | - Adrien Roux
- Tissue Engineering Laboratory, HEPIA HES-SO University of Applied Sciences and Arts Western Switzerland, Geneva, Switzerland
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McDonald M, Sebinger D, Brauns L, Gonzalez-Cano L, Menuchin-Lasowski Y, Mierzejewski M, Psathaki OE, Stumpf A, Wickham J, Rauen T, Schöler H, Jones PD. A mesh microelectrode array for non-invasive electrophysiology within neural organoids. Biosens Bioelectron 2023; 228:115223. [PMID: 36931193 DOI: 10.1016/j.bios.2023.115223] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/13/2023]
Abstract
Organoids are emerging in vitro models of human physiology. Neural models require the evaluation of functional activity of single cells and networks, which is commonly measured by microelectrode arrays. The characteristics of organoids clash with existing in vitro or in vivo microelectrode arrays. With inspiration from implantable mesh electronics and growth of organoids on polymer scaffolds, we fabricated suspended hammock-like mesh microelectrode arrays for neural organoids. We have demonstrated the growth of organoids enveloping these meshes and the culture of organoids on meshes for up to one year. Furthermore, we present proof-of-principle recordings of spontaneous electrical activity across the volume of an organoid. Our concept enables a new class of microelectrode arrays for in vitro models of three-dimensional electrically active tissue.
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Affiliation(s)
- Matthew McDonald
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstr. 55, 72770, Reutlingen, Germany; Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany
| | - David Sebinger
- Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany
| | - Lisa Brauns
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstr. 55, 72770, Reutlingen, Germany; Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany
| | - Laura Gonzalez-Cano
- Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany
| | | | - Michael Mierzejewski
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstr. 55, 72770, Reutlingen, Germany; Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany
| | - Olympia-Ekaterini Psathaki
- Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany; University of Osnabrück, CellNanOs (Center of Cellular Nanoanalytics), Integrated Bioimaging Facility iBiOs, Barbarastr. 11, 49076, Osnabrück, Germany
| | - Angelika Stumpf
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstr. 55, 72770, Reutlingen, Germany
| | - Jenny Wickham
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstr. 55, 72770, Reutlingen, Germany
| | - Thomas Rauen
- Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany.
| | - Hans Schöler
- Max Planck Institute for Molecular Biomedicine, Röntgenstr. 20, 48149, Münster, Germany
| | - Peter D Jones
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstr. 55, 72770, Reutlingen, Germany.
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Cortelli G, Grob L, Patruno L, Cramer T, Mayer D, Fraboni B, Wolfrum B, de Miranda S. Determination of Stiffness and the Elastic Modulus of 3D-Printed Micropillars with Atomic Force Microscopy-Force Spectroscopy. ACS APPLIED MATERIALS & INTERFACES 2023; 15:7602-7609. [PMID: 36706051 PMCID: PMC9923676 DOI: 10.1021/acsami.2c21921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Nowadays, many applications in diverse fields are taking advantage of micropillars such as optics, tribology, biology, and biomedical engineering. Among them, one of the most attractive is three-dimensional microelectrode arrays for in vivo and in vitro studies, such as cellular recording, biosensors, and drug delivery. Depending on the application, the micropillar's optimal mechanical response ranges from soft to stiff. For long-term implantable devices, a mechanical mismatch between the micropillars and the biological tissue must be avoided. For drug delivery patches, micropillars must penetrate the skin without breaking or bending. The accurate mechanical characterization of the micropillar is pivotal in the fabrication and optimization of such devices, as it determines whether the device will fail or not. In this work, we demonstrate an experimental method based only on atomic force microscopy-force spectroscopy that allows us to measure the stiffness of a micropillar and the elastic modulus of its constituent material. We test our method with four different types of 3D inkjet-printed micropillars: silver micropillars sintered at 100 and 150 °C and polyacrylate microstructures with and without a metallic coating. The estimated elastic moduli are found to be comparable with the corresponding bulk values. Furthermore, our findings show that neither the sintering temperature nor the presence of a thin metal coating plays a major role in defining the mechanical properties of the micropillar.
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Affiliation(s)
- Giorgio Cortelli
- Department
of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Viale del Risorgimento 2, 40136 Bologna, Italy
| | - Leroy Grob
- Neuroelectronics,
Munich Institute of Biomedical Engineering, Department of Electrical
Engineering, Technical University of Munich, 85748 Garching, Germany
| | - Luca Patruno
- Department
of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Viale del Risorgimento 2, 40136 Bologna, Italy
| | - Tobias Cramer
- Department
of Physics and Astronomy, University of
Bologna, Viale Berti
Pichat 6/2, 40127 Bologna, Italy
| | - Dirk Mayer
- Institute
of Biological Information Processing (IBI-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Beatrice Fraboni
- Department
of Physics and Astronomy, University of
Bologna, Viale Berti
Pichat 6/2, 40127 Bologna, Italy
| | - Bernhard Wolfrum
- Neuroelectronics,
Munich Institute of Biomedical Engineering, Department of Electrical
Engineering, Technical University of Munich, 85748 Garching, Germany
| | - Stefano de Miranda
- Department
of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Viale del Risorgimento 2, 40136 Bologna, Italy
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Liu F, Zhang M, Xiong G, Han X, Lee VWH, So KF, Chiu K, Xu Y. Trans-Sclera Electrical Stimulation Improves Retinal Function in a Mouse Model of Retinitis Pigmentosa. Life (Basel) 2022; 12:1917. [PMID: 36431052 PMCID: PMC9693292 DOI: 10.3390/life12111917] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/12/2022] [Accepted: 11/14/2022] [Indexed: 11/19/2022] Open
Abstract
Retinitis pigmentosa (RP) is a photoreceptor-degenerating disease with no effective treatment. Trans-corneal electrical stimulation has neuroprotective effects in degenerating retinas, but repeated applications cause corneal injury. To avoid the risk of corneal damage, here we tested whether repetitive trans-sclera electrical stimulation (TsES) protects degenerating retinas in rd10 mice, a model of RP. At postnatal day 20 (P20), the right eyes of rd10 mice were exposed to 30 min of TsES daily or every other day till P25, at the amplitude of 50 or 100 μA, with zero current as the sham. Immunostaining, multi-electrode-array (MEA) recording, and a black-and-white transition box were applied to examine the morphological and functional changes of the treated retina. Functionally, TsES modified the retinal light responses. It also reduced the high spontaneous firing of retinal ganglion cells. TsES at 100 μA but not 50 μA increased the light sensitivities of ganglion cells as well as their signal-to-noise ratios. TsES at 100 μA increased the survival of photoreceptors without improving the visual behavior of rd10 mice. Our data suggest that repetitive TsES improves the retinal function of rd10 mice at the early degenerating stage, therefore, it might be an effective long-term strategy to delay retinal degeneration in RP patients.
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Affiliation(s)
- Feng Liu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Key Laboratory of CNS Regeneration (Ministry of Education), Jinan University, 601 West Huangpu Ave., Guangzhou 510632, China
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China
| | - Mengrong Zhang
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Key Laboratory of CNS Regeneration (Ministry of Education), Jinan University, 601 West Huangpu Ave., Guangzhou 510632, China
| | - Guoyin Xiong
- Department of Ophthalmology, The University of Hong Kong, Hong Kong SAR, China
| | - Xiu Han
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Key Laboratory of CNS Regeneration (Ministry of Education), Jinan University, 601 West Huangpu Ave., Guangzhou 510632, China
| | | | - Kwok-Fai So
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Key Laboratory of CNS Regeneration (Ministry of Education), Jinan University, 601 West Huangpu Ave., Guangzhou 510632, China
- Department of Ophthalmology, The University of Hong Kong, Hong Kong SAR, China
- Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226019, China
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
- Department of Psychology, The University of Hong Kong, Hong Kong SAR, China
| | - Kin Chiu
- Department of Ophthalmology, The University of Hong Kong, Hong Kong SAR, China
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
- Department of Psychology, The University of Hong Kong, Hong Kong SAR, China
| | - Ying Xu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Key Laboratory of CNS Regeneration (Ministry of Education), Jinan University, 601 West Huangpu Ave., Guangzhou 510632, China
- Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226019, China
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7
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Lam D, Fischer NO, Enright HA. Probing function in 3D neuronal cultures: A survey of 3D multielectrode array advances. Curr Opin Pharmacol 2021; 60:255-260. [PMID: 34481335 DOI: 10.1016/j.coph.2021.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/26/2021] [Accepted: 08/02/2021] [Indexed: 12/14/2022]
Abstract
Recent advances in microphysiological systems have made significant strides to include design features that reconstruct key elements found in the brain, and in parallel advance technologies to detect the activity of electrogenic cells that form neural networks. In particular, three-dimensional multielectrode arrays (3D MEAs) are being developed with increasing levels of spatial and temporal precision, difficult to achieve with current 2D MEAs, insertable MEA probes, and/or optical imaging of calcium dynamics. Thus, providing a means to monitor the flow of neural network activity within all three dimensions (X, Y, and Z) of the engineered tissue. In the last 6 years, 3D MEAs, using either bottom-up or top-down designs, have been developed to overcome the current technical challenges in monitoring the functionality of the in vitro systems. Herein, we will report on the design and application of novel 3D MEA prototypes for probing neural activity throughout the 3D neural tissue.
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Affiliation(s)
- Doris Lam
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Nicholas O Fischer
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
| | - Heather A Enright
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
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Soscia DA, Lam D, Tooker AC, Enright HA, Triplett M, Karande P, Peters SKG, Sales AP, Wheeler EK, Fischer NO. A flexible 3-dimensional microelectrode array for in vitro brain models. LAB ON A CHIP 2020; 20:901-911. [PMID: 31976505 DOI: 10.1039/c9lc01148j] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Three-dimensional (3D) in vitro models have become increasingly popular as systems to study cell-cell and cell-ECM interactions dependent on the spatial, mechanical, and chemical cues within the environment of the tissue, which is limited in traditional two-dimensional (2D) models. Although electrophysiological recordings of neuronal action potentials through 2D microelectrode arrays (MEAs) are a common and trusted method of evaluating neuronal function, network communication, and response to chemicals and biologicals, there are currently limited options for measuring electrophysiological activity from many locations simultaneously throughout a 3D network of neurons in vitro. Here, we have developed a thin-film, 3D flexible microelectrode array (3DMEA) that non-invasively interrogates a 3D culture of neurons and can accommodate 256 channels of recording or stimulation. Importantly, the 3DMEA is straightforward to fabricate and integrates with standard commercially available electrophysiology hardware. Polyimide probe arrays were microfabricated on glass substrates and mechanically actuated to collectively lift the arrays into a vertical position, relying solely on plastic deformation of their base hinge regions to maintain vertical alignment. Human induced pluripotent stem cell (hiPSC)-derived neurons and astrocytes were entrapped in a collagen-based hydrogel and seeded onto the 3DMEA, enabling growth of suspended cells in the matrix and the formation and maturation of a neural network around the 3DMEA probes. The 3DMEA supported the growth of functional neurons in 3D with action potential spike and burst activity recorded over 45 days in vitro. This platform is an important step in facilitating noninvasive electrophysiological characterization of 3D networks of electroactive cells in vitro.
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Affiliation(s)
- David A Soscia
- Engineering Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA
| | - Doris Lam
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA.
| | - Angela C Tooker
- Engineering Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA
| | - Heather A Enright
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA.
| | - Michael Triplett
- Engineering Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA
| | - Piyush Karande
- Engineering Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA
| | - Sandra K G Peters
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA.
| | - Ana Paula Sales
- Engineering Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA
| | - Elizabeth K Wheeler
- Engineering Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA
| | - Nicholas O Fischer
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA.
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