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Moslehi S, Rowland C, Smith JH, Watterson WJ, Griffiths W, Montgomery RD, Philliber S, Marlow CA, Perez MT, Taylor RP. Fractal Electronics for Stimulating and Sensing Neural Networks: Enhanced Electrical, Optical, and Cell Interaction Properties. ADVANCES IN NEUROBIOLOGY 2024; 36:849-875. [PMID: 38468067 DOI: 10.1007/978-3-031-47606-8_43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Imagine a world in which damaged parts of the body - an arm, an eye, and ultimately a region of the brain - can be replaced by artificial implants capable of restoring or even enhancing human performance. The associated improvements in the quality of human life would revolutionize the medical world and produce sweeping changes across society. In this chapter, we discuss several approaches to the fabrication of fractal electronics designed to interface with neural networks. We consider two fundamental functions - stimulating electrical signals in the neural networks and sensing the location of the signals as they pass through the network. Using experiments and simulations, we discuss the favorable electrical performances that arise from adopting fractal rather than traditional Euclidean architectures. We also demonstrate how the fractal architecture induces favorable physical interactions with the cells they interact with, including the ability to direct the growth of neurons and glia to specific regions of the neural-electronic interface.
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Affiliation(s)
- S Moslehi
- Physics Department, University of Oregon, Eugene, OR, USA
| | - C Rowland
- Physics Department, University of Oregon, Eugene, OR, USA
| | - J H Smith
- Physics Department, University of Oregon, Eugene, OR, USA
| | - W J Watterson
- Physics Department, University of Oregon, Eugene, OR, USA
| | - W Griffiths
- Physics Department, University of Oregon, Eugene, OR, USA
| | - R D Montgomery
- Physics Department, University of Oregon, Eugene, OR, USA
| | - S Philliber
- Physics Department, University of Oregon, Eugene, OR, USA
| | - C A Marlow
- Physics Department, California Polytechnic State University, San Luis Obispo, CA, USA
| | - M-T Perez
- Department of Clinical Sciences Lund, Division of Ophthalmology, Lund University, Lund, Sweden
| | - R P Taylor
- Physics Department, University of Oregon, Eugene, OR, USA.
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2
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Lin S, Jiang J, Huang K, Li L, He X, Du P, Wu Y, Liu J, Li X, Huang Z, Zhou Z, Yu Y, Gao J, Lei M, Wu H. Advanced Electrode Technologies for Noninvasive Brain-Computer Interfaces. ACS NANO 2023; 17:24487-24513. [PMID: 38064282 DOI: 10.1021/acsnano.3c06781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Brain-computer interfaces (BCIs) have garnered significant attention in recent years due to their potential applications in medical, assistive, and communication technologies. Building on this, noninvasive BCIs stand out as they provide a safe and user-friendly method for interacting with the human brain. In this work, we provide a comprehensive overview of the latest developments and advancements in material, design, and application of noninvasive BCIs electrode technology. We also explore the challenges and limitations currently faced by noninvasive BCI electrode technology and sketch out the technological roadmap from three dimensions: Materials and Design; Performances; Mode and Function. We aim to unite research efforts within the field of noninvasive BCI electrode technology, focusing on the consolidation of shared goals and fostering integrated development strategies among a diverse array of multidisciplinary researchers.
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Affiliation(s)
- Sen Lin
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Jingjing Jiang
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Kai Huang
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
- State Key Laboratory of Information Photonics and Optical Communications and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Lei Li
- National Engineering Research Center of Electric Vehicles, Beijing Institute of Technology, Beijing 100081, China
| | - Xian He
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Peng Du
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Yufeng Wu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Junchen Liu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
- State Key Laboratory of Information Photonics and Optical Communications and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Xilin Li
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
- Advanced Institute for Brain and Intelligence, Guangxi University, Nanning 530004, China
| | - Zhibao Huang
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Zenan Zhou
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Yuanhang Yu
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Jiaxin Gao
- School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Ming Lei
- State Key Laboratory of Information Photonics and Optical Communications and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Hui Wu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
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3
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Erofeev A, Antifeev I, Bolshakova A, Bezprozvanny I, Vlasova O. In Vivo Penetrating Microelectrodes for Brain Electrophysiology. SENSORS (BASEL, SWITZERLAND) 2022; 22:s22239085. [PMID: 36501805 PMCID: PMC9735502 DOI: 10.3390/s22239085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/14/2022] [Accepted: 11/22/2022] [Indexed: 05/13/2023]
Abstract
In recent decades, microelectrodes have been widely used in neuroscience to understand the mechanisms behind brain functions, as well as the relationship between neural activity and behavior, perception and cognition. However, the recording of neuronal activity over a long period of time is limited for various reasons. In this review, we briefly consider the types of penetrating chronic microelectrodes, as well as the conductive and insulating materials for microelectrode manufacturing. Additionally, we consider the effects of penetrating microelectrode implantation on brain tissue. In conclusion, we review recent advances in the field of in vivo microelectrodes.
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Affiliation(s)
- Alexander Erofeev
- Laboratory of Molecular Neurodegeneration, Graduate School of Biomedical Systems and Technologies, Institute of Biomedical Systems and Biotechnology, Peter the Great St. Petersburg Polytechnic University, 195251 Saint Petersburg, Russia
- Correspondence: (A.E.); (O.V.)
| | - Ivan Antifeev
- Laboratory of Methods and Instruments for Genetic and Immunoassay Analysis, Institute for Analytical Instrumentation of the Russian Academy of Sciences, 198095 Saint Petersburg, Russia
| | - Anastasia Bolshakova
- Laboratory of Molecular Neurodegeneration, Graduate School of Biomedical Systems and Technologies, Institute of Biomedical Systems and Biotechnology, Peter the Great St. Petersburg Polytechnic University, 195251 Saint Petersburg, Russia
| | - Ilya Bezprozvanny
- Laboratory of Molecular Neurodegeneration, Graduate School of Biomedical Systems and Technologies, Institute of Biomedical Systems and Biotechnology, Peter the Great St. Petersburg Polytechnic University, 195251 Saint Petersburg, Russia
- Department of Physiology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
| | - Olga Vlasova
- Laboratory of Molecular Neurodegeneration, Graduate School of Biomedical Systems and Technologies, Institute of Biomedical Systems and Biotechnology, Peter the Great St. Petersburg Polytechnic University, 195251 Saint Petersburg, Russia
- Correspondence: (A.E.); (O.V.)
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4
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Moslehi S, Rowland C, Smith JH, Griffiths W, Watterson WJ, Niell CM, Alemán BJ, Perez MT, Taylor RP. Comparison of fractal and grid electrodes for studying the effects of spatial confinement on dissociated retinal neuronal and glial behavior. Sci Rep 2022; 12:17513. [PMID: 36266414 PMCID: PMC9584887 DOI: 10.1038/s41598-022-21742-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 09/30/2022] [Indexed: 01/12/2023] Open
Abstract
Understanding the impact of the geometry and material composition of electrodes on the survival and behavior of retinal cells is of importance for both fundamental cell studies and neuromodulation applications. We investigate how dissociated retinal cells from C57BL/6J mice interact with electrodes made of vertically-aligned carbon nanotubes grown on silicon dioxide substrates. We compare electrodes with different degrees of spatial confinement, specifically fractal and grid electrodes featuring connected and disconnected gaps between the electrodes, respectively. For both electrodes, we find that neuron processes predominantly accumulate on the electrode rather than the gap surfaces and that this behavior is strongest for the grid electrodes. However, the 'closed' character of the grid electrode gaps inhibits glia from covering the gap surfaces. This lack of glial coverage for the grids is expected to have long-term detrimental effects on neuronal survival and electrical activity. In contrast, the interconnected gaps within the fractal electrodes promote glial coverage. We describe the differing cell responses to the two electrodes and hypothesize that there is an optimal geometry that maximizes the positive response of both neurons and glia when interacting with electrodes.
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Affiliation(s)
- Saba Moslehi
- grid.170202.60000 0004 1936 8008Physics Department, 1371 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Materials Science Institute, 1252 University of Oregon, Eugene, OR 97403 USA
| | - Conor Rowland
- grid.170202.60000 0004 1936 8008Physics Department, 1371 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Materials Science Institute, 1252 University of Oregon, Eugene, OR 97403 USA
| | - Julian H. Smith
- grid.170202.60000 0004 1936 8008Physics Department, 1371 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Materials Science Institute, 1252 University of Oregon, Eugene, OR 97403 USA
| | - Willem Griffiths
- grid.170202.60000 0004 1936 8008Department of Biology, 1210 University of Oregon, Eugene, OR 97403 USA
| | - William J. Watterson
- grid.170202.60000 0004 1936 8008Physics Department, 1371 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Materials Science Institute, 1252 University of Oregon, Eugene, OR 97403 USA
| | - Cristopher M. Niell
- grid.170202.60000 0004 1936 8008Department of Biology, 1210 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403 USA
| | - Benjamín J. Alemán
- grid.170202.60000 0004 1936 8008Physics Department, 1371 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Materials Science Institute, 1252 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Oregon Center for Optical, Molecular and Quantum Science, 1274 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Phil and Penny Knight Campus for Accelerating Scientific Impact, 1505 University of Oregon, Franklin Blvd., Eugene, OR 97403 USA
| | - Maria-Thereza Perez
- grid.4514.40000 0001 0930 2361Division of Ophthalmology, Department of Clinical Sciences Lund, Lund University, 221 84 Lund, Sweden ,grid.4514.40000 0001 0930 2361NanoLund, Lund University, 221 00 Lund, Sweden
| | - Richard P. Taylor
- grid.170202.60000 0004 1936 8008Physics Department, 1371 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Materials Science Institute, 1252 University of Oregon, Eugene, OR 97403 USA ,grid.170202.60000 0004 1936 8008Phil and Penny Knight Campus for Accelerating Scientific Impact, 1505 University of Oregon, Franklin Blvd., Eugene, OR 97403 USA
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5
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Moorthy VM, Varatharajan P, Rathnasami JD, Srivastava VM. G-Optrode Bio-Interfaces for Non-Invasive Optical Cell Stimulation: Design and Evaluation. BIOSENSORS 2022; 12:808. [PMID: 36290945 PMCID: PMC9599383 DOI: 10.3390/bios12100808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/24/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Biocompatibility and potential efficacy in biological applications rely on the bio-interactions of graphene nanoparticles with biological tissues. Analyzing and modulating cellular and device-level activity requires non-invasive electrical stimulation of cells. To address these needs, G-optrodes, bio-interfaces based on graphene, have been developed. These devices use light to stimulate cells without modifying their genetic code. Optoelectronic capabilities, in particular the capacity to transform light energy into electrical energy, will be maintained throughout the procedures of neural stimulation. G-optrodes have also been studied as thin films on a range of substrates, and they have been designed to function at a very small scale. This study examines the impact of G-optrode-based substrate designs on the optical stimulation of pheochromocytoma (PC-12). Graphene electrodes, known as G-optrodes, are responsible for converting light into electrical pulses with stimulating effects. G-optrode bio-interfaces provide a stimulus that is independent of wavelength range but is sensitive to changes in illuminance. The authors have performed a comprehensive investigation based on the correct effects of the medication in vitro, employing substrate-based G-optrode biointerfaces. In substrate-based systems, the authors have proven that graphene is biocompatible. PC-12 cells were cultured on graphene for 7 days. Based on the findings, 20-nm and 50-nm thick G-optrodes are being studied for possible use in biological and artificial retinal applications. The findings of this study highlight the significance of biocompatibility in the selection and use of G-optrodes for biomedical purposes.
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Affiliation(s)
- Vijai M. Moorthy
- Department of Electronic Engineering, Howard College, University of KwaZulu-Natal, Durban 4041, South Africa
| | | | - Joseph D. Rathnasami
- Department of Electronics and Instrumentation Engineering, Annamalai University, Chidambaram 608 002, India
| | - Viranjay M. Srivastava
- Department of Electronic Engineering, Howard College, University of KwaZulu-Natal, Durban 4041, South Africa
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Moslehi S, Rowland C, Smith JH, Watterson WJ, Miller D, Niell CM, Alemán BJ, Perez MT, Taylor RP. Controlled assembly of retinal cells on fractal and Euclidean electrodes. PLoS One 2022; 17:e0265685. [PMID: 35385490 PMCID: PMC8985931 DOI: 10.1371/journal.pone.0265685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/04/2022] [Indexed: 11/25/2022] Open
Abstract
Controlled assembly of retinal cells on artificial surfaces is important for fundamental cell research and medical applications. We investigate fractal electrodes with branches of vertically-aligned carbon nanotubes and silicon dioxide gaps between the branches that form repeating patterns spanning from micro- to milli-meters, along with single-scaled Euclidean electrodes. Fluorescence and electron microscopy show neurons adhere in large numbers to branches while glial cells cover the gaps. This ensures neurons will be close to the electrodes’ stimulating electric fields in applications. Furthermore, glia won’t hinder neuron-branch interactions but will be sufficiently close for neurons to benefit from the glia’s life-supporting functions. This cell ‘herding’ is adjusted using the fractal electrode’s dimension and number of repeating levels. We explain how this tuning facilitates substantial glial coverage in the gaps which fuels neural networks with small-world structural characteristics. The large branch-gap interface then allows these networks to connect to the neuron-rich branches.
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Affiliation(s)
- Saba Moslehi
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
| | - Conor Rowland
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
| | - Julian H. Smith
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
| | - William J. Watterson
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
| | - David Miller
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
- Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, Eugene, Oregon, United States of America
| | - Cristopher M. Niell
- Institute of Neuroscience, University of Oregon, Eugene, Oregon, United States of America
- Department of Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Benjamín J. Alemán
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
- Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, Eugene, Oregon, United States of America
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, Oregon, United States of America
| | - Maria-Thereza Perez
- Division of Ophthalmology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
- NanoLund, Lund University, Lund, Sweden
- * E-mail: (RPT); (MTP)
| | - Richard P. Taylor
- Physics Department, University of Oregon, Eugene, Oregon, United States of America
- Materials Science Institute, University of Oregon, Eugene, Oregon, United States of America
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, Oregon, United States of America
- * E-mail: (RPT); (MTP)
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Vėbraitė I, Hanein Y. Soft Devices for High-Resolution Neuro-Stimulation: The Interplay Between Low-Rigidity and Resolution. FRONTIERS IN MEDICAL TECHNOLOGY 2022; 3:675744. [PMID: 35047928 PMCID: PMC8757739 DOI: 10.3389/fmedt.2021.675744] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/14/2021] [Indexed: 12/27/2022] Open
Abstract
The field of neurostimulation has evolved over the last few decades from a crude, low-resolution approach to a highly sophisticated methodology entailing the use of state-of-the-art technologies. Neurostimulation has been tested for a growing number of neurological applications, demonstrating great promise and attracting growing attention in both academia and industry. Despite tremendous progress, long-term stability of the implants, their large dimensions, their rigidity and the methods of their introduction and anchoring to sensitive neural tissue remain challenging. The purpose of this review is to provide a concise introduction to the field of high-resolution neurostimulation from a technological perspective and to focus on opportunities stemming from developments in materials sciences and engineering to reduce device rigidity while optimizing electrode small dimensions. We discuss how these factors may contribute to smaller, lighter, softer and higher electrode density devices.
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Affiliation(s)
- Ieva Vėbraitė
- School of Electrical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Yael Hanein
- School of Electrical Engineering, Tel Aviv University, Tel Aviv, Israel
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8
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Green RA. Possibilities in bioelectronics: Super humans or science fiction? APL Bioeng 2021; 5:040401. [PMID: 34964001 DOI: 10.1063/5.0079530] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/08/2021] [Indexed: 12/16/2022] Open
Abstract
Recent years have led to a rapid increase in the development of neurotechnologies for diagnosis, monitoring, and treatment of conditions with neurological targets. The central driving force has been the need for next-generation devices to treat neural injury and disease, where current pharmaceutical or conventional bioelectronics have been unable to impart sufficient therapeutic effects. The advent of new therapies and advanced technologies has resulted in a reemergence of the concept of superhuman performance. This is a hypothetical possibility that is enabled when bionics are used to augment the neural system and has included the notions of improved cognitive ability and enhancement of hearing and seeing beyond the limitations of a healthy human. It is quite conceivable that a bionic eye could be used for night vision; however, the damage to both the neural system and surrounding tissues in placing such a device is only considered acceptable in the case of a patient that can obtain improvement in quality of life. There are also critical limitations that have hindered clinical translation of high-resolution neural interfaces, despite significant advances in biomaterial and bioelectronics technologies, including the advent of biohybrid devices. Surgical damage and foreign body reactions to such devices can be reduced but not eliminated, and these engineering solutions to reduce inflammation present additional challenges to the long-term performance and medical regulation. As a result, while bioelectronics has seen concepts from science fiction realized, there remains a significant gap to their use as enhancements beyond medical therapies.
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Affiliation(s)
- Rylie A Green
- Department of Bioengineering, Imperial College London, London SW7 2AS, United Kingdom
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9
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Vajrala VS, Saunier V, Nowak LG, Flahaut E, Bergaud C, Maziz A. Nanofibrous PEDOT-Carbon Composite on Flexible Probes for Soft Neural Interfacing. Front Bioeng Biotechnol 2021; 9:780197. [PMID: 34900968 PMCID: PMC8662776 DOI: 10.3389/fbioe.2021.780197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/12/2021] [Indexed: 11/25/2022] Open
Abstract
In this study, we report a flexible implantable 4-channel microelectrode probe coated with highly porous and robust nanocomposite of poly (3,4-ethylenedioxythiophene) (PEDOT) and carbon nanofiber (CNF) as a solid doping template for high-performance in vivo neuronal recording and stimulation. A simple yet well-controlled deposition strategy was developed via in situ electrochemical polymerization technique to create a porous network of PEDOT and CNFs on a flexible 4-channel gold microelectrode probe. Different morphological and electrochemical characterizations showed that they exhibit remarkable and superior electrochemical properties, yielding microelectrodes combining high surface area, low impedance (16.8 ± 2 MΩ µm2 at 1 kHz) and elevated charge injection capabilities (7.6 ± 1.3 mC/cm2) that exceed those of pure and composite PEDOT layers. In addition, the PEDOT-CNF composite electrode exhibited extended biphasic charge cycle endurance and excellent performance under accelerated lifetime testing, resulting in a negligible physical delamination and/or degradation for long periods of electrical stimulation. In vitro testing on mouse brain slices showed that they can record spontaneous oscillatory field potentials as well as single-unit action potentials and allow to safely deliver electrical stimulation for evoking field potentials. The combined superior electrical properties, durability and 3D microstructure topology of the PEDOT-CNF composite electrodes demonstrate outstanding potential for developing future neural surface interfacing applications.
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Affiliation(s)
| | - Valentin Saunier
- Laboratory for Analysis and Architecture of Systems (LAAS), CNRS, Toulouse, France
| | - Lionel G Nowak
- Centre de Recherche Cerveau et Cognition (CerCo), CNRS, Toulouse, France
| | | | - Christian Bergaud
- Laboratory for Analysis and Architecture of Systems (LAAS), CNRS, Toulouse, France
| | - Ali Maziz
- Laboratory for Analysis and Architecture of Systems (LAAS), CNRS, Toulouse, France
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10
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Yin P, Liu Y, Xiao L, Zhang C. Advanced Metallic and Polymeric Coatings for Neural Interfacing: Structures, Properties and Tissue Responses. Polymers (Basel) 2021; 13:2834. [PMID: 34451372 PMCID: PMC8401399 DOI: 10.3390/polym13162834] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/15/2021] [Accepted: 08/17/2021] [Indexed: 02/07/2023] Open
Abstract
Neural electrodes are essential for nerve signal recording, neurostimulation, neuroprosthetics and neuroregeneration, which are critical for the advancement of brain science and the establishment of the next-generation brain-electronic interface, central nerve system therapeutics and artificial intelligence. However, the existing neural electrodes suffer from drawbacks such as foreign body responses, low sensitivity and limited functionalities. In order to overcome the drawbacks, efforts have been made to create new constructions and configurations of neural electrodes from soft materials, but it is also more practical and economic to improve the functionalities of the existing neural electrodes via surface coatings. In this article, recently reported surface coatings for neural electrodes are carefully categorized and analyzed. The coatings are classified into different categories based on their chemical compositions, i.e., metals, metal oxides, carbons, conducting polymers and hydrogels. The characteristic microstructures, electrochemical properties and fabrication methods of the coatings are comprehensively presented, and their structure-property correlations are discussed. Special focus is given to the biocompatibilities of the coatings, including their foreign-body response, cell affinity, and long-term stability during implantation. This review article can provide useful and sophisticated insights into the functional design, material selection and structural configuration for the next-generation multifunctional coatings of neural electrodes.
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Affiliation(s)
| | - Yang Liu
- Department of Biomedical Engineering, Sun Yat-sen University, Shenzhen 518107, China; (P.Y.); (L.X.)
| | | | - Chao Zhang
- Department of Biomedical Engineering, Sun Yat-sen University, Shenzhen 518107, China; (P.Y.); (L.X.)
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11
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Abend A, Steele C, Jahnke HG, Zink M. Adhesion of Neurons and Glial Cells with Nanocolumnar TiN Films for Brain-Machine Interfaces. Int J Mol Sci 2021; 22:8588. [PMID: 34445294 PMCID: PMC8395253 DOI: 10.3390/ijms22168588] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/29/2021] [Accepted: 08/07/2021] [Indexed: 12/12/2022] Open
Abstract
Coupling of cells to biomaterials is a prerequisite for most biomedical applications; e.g., neuroelectrodes can only stimulate brain tissue in vivo if the electric signal is transferred to neurons attached to the electrodes' surface. Besides, cell survival in vitro also depends on the interaction of cells with the underlying substrate materials; in vitro assays such as multielectrode arrays determine cellular behavior by electrical coupling to the adherent cells. In our study, we investigated the interaction of neurons and glial cells with different electrode materials such as TiN and nanocolumnar TiN surfaces in contrast to gold and ITO substrates. Employing single-cell force spectroscopy, we quantified short-term interaction forces between neuron-like cells (SH-SY5Y cells) and glial cells (U-87 MG cells) for the different materials and contact times. Additionally, results were compared to the spreading dynamics of cells for different culture times as a function of the underlying substrate. The adhesion behavior of glial cells was almost independent of the biomaterial and the maximum growth areas were already seen after one day; however, adhesion dynamics of neurons relied on culture material and time. Neurons spread much better on TiN and nanocolumnar TiN and also formed more neurites after three days in culture. Our designed nanocolumnar TiN offers the possibility for building miniaturized microelectrode arrays for impedance spectroscopy without losing detection sensitivity due to a lowered self-impedance of the electrode. Hence, our results show that this biomaterial promotes adhesion and spreading of neurons and glial cells, which are important for many biomedical applications in vitro and in vivo.
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Affiliation(s)
- Alice Abend
- Research Group Biotechnology and Biomedicine, Faculty of Physics and Earth Sciences, Peter Debye Institute for Soft Matter Physics, Leipzig University, Linnéstraße 5, 04103 Leipzig, Germany;
| | - Chelsie Steele
- Research Group Biotechnology and Biomedicine, Faculty of Physics and Earth Sciences, Peter Debye Institute for Soft Matter Physics, Leipzig University, Linnéstraße 5, 04103 Leipzig, Germany;
| | - Heinz-Georg Jahnke
- Centre for Biotechnology and Biomedicine, Molecular Biological-Biochemical Processing Technology, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany;
| | - Mareike Zink
- Research Group Biotechnology and Biomedicine, Faculty of Physics and Earth Sciences, Peter Debye Institute for Soft Matter Physics, Leipzig University, Linnéstraße 5, 04103 Leipzig, Germany;
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12
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Mathur V, Talapatra S, Kar S, Hennighausen Z. In Vivo Partial Restoration of Neural Activity across Severed Mouse Spinal Cord Bridged with Ultralong Carbon Nanotubes. ACS APPLIED BIO MATERIALS 2021; 4:4071-4078. [DOI: 10.1021/acsabm.1c00248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Vineet Mathur
- Department of Physics, Northeastern University, Boston, Massachusetts 02115, United States
| | - Saikat Talapatra
- Department of Physics, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Swastik Kar
- Department of Physics, Northeastern University, Boston, Massachusetts 02115, United States
| | - Zachariah Hennighausen
- Department of Physics, Northeastern University, Boston, Massachusetts 02115, United States
- NRC Postdoc Residing at the Materials Science and Technology Division, United States Naval Research Laboratory, Washington, D.C. 20375, United States
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13
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Chang AY, Siddiqui S, Arumugam PU. Nafion and Multiwall Carbon Nanotube Modified Ultrananocrystalline Diamond Microelectrodes for Detection of Dopamine and Serotonin. MICROMACHINES 2021; 12:523. [PMID: 34066363 PMCID: PMC8148102 DOI: 10.3390/mi12050523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 04/28/2021] [Accepted: 05/03/2021] [Indexed: 01/21/2023]
Abstract
Neurochemicals play a critical role in the function of the human brain in healthy and diseased states. Here, we have investigated three types of microelectrodes, namely boron-doped ultrananocrystalline diamond (BDUNCD), nafion-modified BDUNCD, and nafion-multi-walled carbon nanotube (MWCNT)-modified BDUNCD microelectrodes for long-term neurochemical detection. A ~50 nm-thick nafion-200-nm-thick MWCNT-modified BDUNCD microelectrode provided an excellent combination of sensitivity and selectivity for the detection of dopamine (DA; 6.75 μA μM-1 cm-2) and serotonin (5-HT; 4.55 μA μM-1 cm-2) in the presence of excess amounts of ascorbic acid (AA), the most common interferent. Surface stability studies employing droplet-based microfluidics demonstrate rapid response time (<2 s) and low limits of detection (5.4 ± 0.40 nM). Furthermore, we observed distinguishable DA and 5-HT current peaks in a ternary mixture during long-term stability studies (up to 9 h) with nafion-MWCNT-modified BDUNCD microelectrodes. Reduced fouling on the modified BDUNCD microelectrode surface offers significant advantages for their use in long-term neurochemical detection as compared to those of prior-art microelectrodes.
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Affiliation(s)
- An-Yi Chang
- Institute for Micromanufacturing (IfM), Louisiana Tech University, Ruston, LA 71272, USA;
- Center for Biomedical Engineering and Rehabilitation Science (CBERS), Louisiana Tech University, Ruston, LA 71272, USA
| | - Shabnam Siddiqui
- Department of Chemistry and Physics, Louisiana State University Shreveport, Shreveport, LA 71115, USA;
| | - Prabhu U. Arumugam
- Institute for Micromanufacturing (IfM), Louisiana Tech University, Ruston, LA 71272, USA;
- Center for Biomedical Engineering and Rehabilitation Science (CBERS), Louisiana Tech University, Ruston, LA 71272, USA
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14
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Foremny K, Konerding WS, Behrens A, Baumhoff P, Froriep UP, Kral A, Doll T. Carbon-Nanotube-Coated Surface Electrodes for Cortical Recordings In Vivo. NANOMATERIALS 2021; 11:nano11041029. [PMID: 33920671 PMCID: PMC8073035 DOI: 10.3390/nano11041029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/12/2021] [Accepted: 04/15/2021] [Indexed: 11/16/2022]
Abstract
Current developments of electrodes for neural recordings address the need of biomedical research and applications for high spatial acuity in electrophysiological recordings. One approach is the usage of novel materials to overcome electrochemical constraints of state-of-the-art metal contacts. Promising materials are carbon nanotubes (CNTs), as they are well suited for neural interfacing. The CNTs increase the effective contact surface area to decrease high impedances while keeping minimal contact diameters. However, to prevent toxic dissolving of CNTs, an appropriate surface coating is required. In this study, we tested flexible surface electrocorticographic (ECoG) electrodes, coated with a CNT-silicone rubber composite. First, we describe the outcome of surface etching, which exposes the contact nanostructure while anchoring the CNTs. Subsequently, the ECoG electrodes were used for acute in vivo recordings of auditory evoked potentials from the guinea pig auditory cortex. Both the impedances and the signal-to-noise ratios of coated contacts were similar to uncoated gold contacts. This novel approach for a safe application of CNTs, embedded in a surface etched silicone rubber, showed promising results but did not lead to improvements during acute recordings.
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Affiliation(s)
- Katharina Foremny
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
- Correspondence:
| | - Wiebke S. Konerding
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Ailke Behrens
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Peter Baumhoff
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Ulrich P. Froriep
- Division of Translational Biomedical Engineering, Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, 30625 Hannover, Germany;
| | - Andrej Kral
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Theodor Doll
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
- Division of Translational Biomedical Engineering, Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, 30625 Hannover, Germany;
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15
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Human Eye Optics within a Non-Euclidian Geometrical Approach and Some Implications in Vision Prosthetics Design. Biomolecules 2021; 11:biom11020215. [PMID: 33557081 PMCID: PMC7913825 DOI: 10.3390/biom11020215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 11/25/2022] Open
Abstract
An analogy with our previously published theory on the ionospheric auroral gyroscope provides a new perspective in human eye optics. Based on cone cells’ real distribution, we model the human eye macula as a pseudospherical surface. This allows the rigorous description of the photoreceptor cell densities in the parafoveal zones modeled further by an optimized paving method. The hexagonal photoreceptors’ distribution has been optimally projected on the elliptical pseudosphere, thus designing a prosthetic array counting almost 7000 pixel points. Thanks to the high morphological similarities to a normal human retina, the visual prosthesis performance in camera-free systems might be significantly improved.
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16
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Forro C, Caron D, Angotzi GN, Gallo V, Berdondini L, Santoro F, Palazzolo G, Panuccio G. Electrophysiology Read-Out Tools for Brain-on-Chip Biotechnology. MICROMACHINES 2021; 12:124. [PMID: 33498905 PMCID: PMC7912435 DOI: 10.3390/mi12020124] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 02/07/2023]
Abstract
Brain-on-Chip (BoC) biotechnology is emerging as a promising tool for biomedical and pharmaceutical research applied to the neurosciences. At the convergence between lab-on-chip and cell biology, BoC couples in vitro three-dimensional brain-like systems to an engineered microfluidics platform designed to provide an in vivo-like extrinsic microenvironment with the aim of replicating tissue- or organ-level physiological functions. BoC therefore offers the advantage of an in vitro reproduction of brain structures that is more faithful to the native correlate than what is obtained with conventional cell culture techniques. As brain function ultimately results in the generation of electrical signals, electrophysiology techniques are paramount for studying brain activity in health and disease. However, as BoC is still in its infancy, the availability of combined BoC-electrophysiology platforms is still limited. Here, we summarize the available biological substrates for BoC, starting with a historical perspective. We then describe the available tools enabling BoC electrophysiology studies, detailing their fabrication process and technical features, along with their advantages and limitations. We discuss the current and future applications of BoC electrophysiology, also expanding to complementary approaches. We conclude with an evaluation of the potential translational applications and prospective technology developments.
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Affiliation(s)
- Csaba Forro
- Tissue Electronics, Fondazione Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci, 53-80125 Naples, Italy; (C.F.); (F.S.)
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Davide Caron
- Enhanced Regenerative Medicine, Fondazione Istituto Italiano di Tecnologia, Via Morego, 30-16163 Genova, Italy; (D.C.); (V.G.)
| | - Gian Nicola Angotzi
- Microtechnology for Neuroelectronics, Fondazione Istituto Italiano di Tecnologia, Via Morego, 30-16163 Genova, Italy; (G.N.A.); (L.B.)
| | - Vincenzo Gallo
- Enhanced Regenerative Medicine, Fondazione Istituto Italiano di Tecnologia, Via Morego, 30-16163 Genova, Italy; (D.C.); (V.G.)
| | - Luca Berdondini
- Microtechnology for Neuroelectronics, Fondazione Istituto Italiano di Tecnologia, Via Morego, 30-16163 Genova, Italy; (G.N.A.); (L.B.)
| | - Francesca Santoro
- Tissue Electronics, Fondazione Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci, 53-80125 Naples, Italy; (C.F.); (F.S.)
| | - Gemma Palazzolo
- Enhanced Regenerative Medicine, Fondazione Istituto Italiano di Tecnologia, Via Morego, 30-16163 Genova, Italy; (D.C.); (V.G.)
| | - Gabriella Panuccio
- Enhanced Regenerative Medicine, Fondazione Istituto Italiano di Tecnologia, Via Morego, 30-16163 Genova, Italy; (D.C.); (V.G.)
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17
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Colour-sensitive conjugated polymer inkjet-printed pixelated artificial retina model studied via a bio-hybrid photovoltaic device. Sci Rep 2020; 10:21457. [PMID: 33293628 PMCID: PMC7722856 DOI: 10.1038/s41598-020-77819-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/20/2020] [Indexed: 12/13/2022] Open
Abstract
In recent years, organic electronic materials have been shown to be a promising tool, even transplanted in vivo, for transducing light stimuli to non-functioning retinas. Here we developed a bio-hybrid optoelectronic device consisting of patterned organic polymer semiconductors interfaced with an electrolyte solution in a closed sandwich architecture in order to study the photo-response of photosensitive semiconducting layers or patterns in an environment imitating biological extracellular fluids. We demonstrate an artificial retina model composed of on an array of 42,100 pixels made of three different conjugated polymers via inkjet printing with 110 pixels/mm2 packing density. Photo-sensing through three-colour pixelation allows to resolve incoming light spectrally and spatially. The compact colour sensitive optoelectronic device represents an easy-to-handle photosensitive platform for the study of the photo response of artificial retina systems.
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18
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A simultaneous optical and electrical in-vitro neuronal recording system to evaluate microelectrode performance. PLoS One 2020; 15:e0237709. [PMID: 32817653 PMCID: PMC7440637 DOI: 10.1371/journal.pone.0237709] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 07/31/2020] [Indexed: 11/24/2022] Open
Abstract
Objectives In this paper, we aim to detail the setup of a high spatio-temporal resolution, electrical recording system utilising planar microelectrode arrays with simultaneous optical imaging suitable for evaluating microelectrode performance with a proposed ′performance factor′ metric. Methods Techniques that would facilitate low noise electrical recordings were coupled with voltage sensitive dyes and neuronal activity was recorded both electrically via a customised amplification system and optically via a high speed CMOS camera. This technique was applied to characterise microelectrode recording performance of gold and poly(3,4-ethylenedioxythiophene)/polystyrene sulfonate (PEDOT/PSS) coated electrodes through traditional signal to noise (SNR) calculations as well as the proposed performance factor. Results Neuronal activity was simultaneously recorded using both electrical and optical techniques and this activity was confirmed via tetrodotoxin application to inhibit action potential firing. PEDOT/PSS outperformed gold using both measurements, however, the performance factor metric estimated a 3 fold improvement in signal transduction when compared to gold, whereas SNR estimated an 8 fold improvement when compared to gold. Conclusion The design and functionality of a system to record from neurons both electrically, through microelectrode arrays, and optically via voltage sensitive dyes was successfully achieved. Significance The high spatiotemporal resolution of both electrical and optical methods will allow for an array of applications such as improved detection of subthreshold synaptic events, validation of spike sorting algorithms and a provides a robust evaluation of extracellular microelectrode performance.
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19
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Chen N, Luo B, Patil AC, Wang J, Gammad GGL, Yi Z, Liu X, Yen SC, Ramakrishna S, Thakor NV. Nanotunnels within Poly(3,4-ethylenedioxythiophene)-Carbon Nanotube Composite for Highly Sensitive Neural Interfacing. ACS NANO 2020; 14:8059-8073. [PMID: 32579337 DOI: 10.1021/acsnano.0c00672] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Neural electrodes are developed for direct communication with neural tissues for theranostics. Although various strategies have been employed to improve performance, creating an intimate electrode-tissue interface with high electrical fidelity remains a great challenge. Here, we report the rational design of a tunnel-like electrode coating comprising poly(3,4-ethylenedioxythiophene) (PEDOT) and carbon nanotubes (CNTs) for highly sensitive neural recording. The coated electrode shows a 50-fold reduction in electrochemical impedance at the biologically relevant frequency of 1 kHz, compared to the bare gold electrode. The incorporation of CNT significantly reinforces the nanotunnel structure and improves coating adhesion by ∼1.5 fold. In vitro primary neuron culture confirms an intimate contact between neurons and the PEDOT-CNT nanotunnel. During acute in vivo nerve recording, the coated electrode enables the capture of high-fidelity neural signals with low susceptibility to electrical noise and reveals the potential for precisely decoding sensory information through mechanical and thermal stimulation. These findings indicate that the PEDOT-CNT nanotunnel composite serves as an active interfacing material for neural electrodes, contributing to neural prosthesis and brain-machine interface.
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Affiliation(s)
- Nuan Chen
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
- SINAPSE Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore 117456, Singapore
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | - Baiwen Luo
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | - Anoop C Patil
- SINAPSE Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore 117456, Singapore
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | - Jiahui Wang
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | | | - Zhigao Yi
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Xiaogang Liu
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Shih-Cheng Yen
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Seeram Ramakrishna
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
| | - Nitish V Thakor
- SINAPSE Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore 117456, Singapore
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
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20
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Pavone L, Moyanova S, Mastroiacovo F, Fazi L, Busceti C, Gaglione A, Martinello K, Fucile S, Bucci D, Prioriello A, Nicoletti F, Fornai F, Morales P, Senesi R. Chronic neural interfacing with cerebral cortex using single-walled carbon nanotube-polymer grids. J Neural Eng 2020; 17:036032. [PMID: 32485702 DOI: 10.1088/1741-2552/ab98db] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The development of electrode arrays able to reliably record brain electrical activity is a critical issue in brain machine interface (BMI) technology. In the present study we undertook a comprehensive physico-chemical, physiological, histological and immunohistochemical characterization of new single-walled carbon nanotubes (SWCNT)-based electrode arrays grafted onto medium-density polyethylene (MD-PE) films. APPROACH The long-term electrical stability, flexibility, and biocompatibility of the SWCNT arrays were investigated in vivo in laboratory rats by two-months recording and analysis of subdural electrocorticogram (ECoG). Ex-vivo characterization of a thin flexible and single probe SWCNT/polymer electrode is also provided. MAIN RESULTS The SWCNT arrays were able to capture high quality and very stable ECoG signals across 8 weeks. The histological and immunohistochemical analyses demonstrated that SWCNT arrays show promising biocompatibility properties and may be used in chronic conditions. The SWCNT-based arrays are flexible and stretchable, providing low electrode-tissue impedance, and, therefore, high compliance with the irregular topography of the cortical surface. Finally, reliable evoked synaptic local field potentials in rat brain slices were recorded using a special SWCNT-polymer-based flexible electrode. SIGNIFICANCE The results demonstrate that the SWCNT arrays grafted in MD-PE are suitable for manufacturing flexible devices for subdural ECoG recording and might represent promising candidates for long-term neural implants for epilepsy monitoring or neuroprosthetic BMI.
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Affiliation(s)
- Luigi Pavone
- Department of Life and Health 'V. Tiberio', University of Molise, Campobasso, Italy. IRCCS Neuromed, Via Atinense 18, 86077, Pozzilli (IS), Italy. These authors contributed equally. Author to whom any correspondence should be addressed
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21
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Fan B, Rusinek CA, Thompson CH, Setien M, Guo Y, Rechenberg R, Gong Y, Weber AJ, Becker MF, Purcell E, Li W. Flexible, diamond-based microelectrodes fabricated using the diamond growth side for neural sensing. MICROSYSTEMS & NANOENGINEERING 2020; 6:42. [PMID: 32685185 PMCID: PMC7355183 DOI: 10.1038/s41378-020-0155-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/06/2020] [Accepted: 03/25/2020] [Indexed: 05/02/2023]
Abstract
Diamond possesses many favorable properties for biochemical sensors, including biocompatibility, chemical inertness, resistance to biofouling, an extremely wide potential window, and low double-layer capacitance. The hardness of diamond, however, has hindered its applications in neural implants due to the mechanical property mismatch between diamond and soft nervous tissues. Here, we present a flexible, diamond-based microelectrode probe consisting of multichannel boron-doped polycrystalline diamond (BDD) microelectrodes on a soft Parylene C substrate. We developed and optimized a wafer-scale fabrication approach that allows the use of the growth side of the BDD thin film as the sensing surface. Compared to the nucleation surface, the BDD growth side exhibited a rougher morphology, a higher sp 3 content, a wider water potential window, and a lower background current. The dopamine (DA) sensing capability of the BDD growth surface electrodes was validated in a 1.0 mM DA solution, which shows better sensitivity and stability than the BDD nucleation surface electrodes. The results of these comparative studies suggest that using the BDD growth surface for making implantable microelectrodes has significant advantages in terms of the sensitivity, selectivity, and stability of a neural implant. Furthermore, we validated the functionality of the BDD growth side electrodes for neural recordings both in vitro and in vivo. The biocompatibility of the microcrystalline diamond film was also assessed in vitro using rat cortical neuron cultures.
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Affiliation(s)
- Bin Fan
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI USA
| | - Cory A. Rusinek
- Fraunhofer USA Center for Coatings and Diamond Technologies, East Lansing, MI USA
| | - Cort H. Thompson
- Department of Biomedical Engineering, Michigan State University, East Lansing, MI USA
| | - Monica Setien
- Department of Biomedical Engineering, Michigan State University, East Lansing, MI USA
| | - Yue Guo
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI USA
| | - Robert Rechenberg
- Fraunhofer USA Center for Coatings and Diamond Technologies, East Lansing, MI USA
| | - Yan Gong
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI USA
| | - Arthur J. Weber
- Department of Physiology, Michigan State University, East Lansing, MI USA
| | - Michael F. Becker
- Fraunhofer USA Center for Coatings and Diamond Technologies, East Lansing, MI USA
| | - Erin Purcell
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI USA
- Department of Biomedical Engineering, Michigan State University, East Lansing, MI USA
| | - Wen Li
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI USA
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22
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Hondrich TJJ, Lenyk B, Shokoohimehr P, Kireev D, Maybeck V, Mayer D, Offenhäusser A. MEA Recordings and Cell-Substrate Investigations with Plasmonic and Transparent, Tunable Holey Gold. ACS APPLIED MATERIALS & INTERFACES 2019; 11:46451-46461. [PMID: 31752486 DOI: 10.1021/acsami.9b14948] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Microelectrode arrays are widely used in different fields such as neurobiology or biomedicine to read out electrical signals from cells or biomolecules. One way to improve microelectrode applications is the development of novel electrode materials with enhanced or additional functionality. In this study, we fabricated macroelectrodes and microelectrode arrays containing gold penetrated by nanohole arrays as a conductive layer. We used this holey gold to optically excite surface plasmon polaritons, which lead to a strong increase in transparency, an effect that is further enhanced by the plasmon's interaction with cell culture medium. By varying the nanohole diameter in finite-difference time domain simulations, we demonstrate that the transmission can be increased to above 70% with its peak at a wavelength depending on the holey gold's lattice constant. Further, we demonstrate that the novel transparent microelectrode arrays are as suitable for recording cellular electrical activity as standard devices. Moreover, we prove using spectral measurements and finite-difference time domain simulations that plasmonically induced transmission peaks of holey gold red-shift upon sensing medium or cells in close vicinity (<30 nm) to the substrate. Thus, we establish plasmonic and transparent holey gold as a tunable material suitable for cellular electrical recordings and biosensing applications.
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Affiliation(s)
- Timm J J Hondrich
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
- RWTH Aachen University , Aachen 52062 , Germany
| | - Bohdan Lenyk
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
- Department of Physics , University of Konstanz , 78464 Konstanz , Germany
| | - Pegah Shokoohimehr
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
- RWTH Aachen University , Aachen 52062 , Germany
| | - Dmitry Kireev
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
- Department of Electrical and Computer Engineering , University of Texas at Austin , Austin , Texas 78712 , United States
| | - Vanessa Maybeck
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
| | - Dirk Mayer
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
| | - Andreas Offenhäusser
- Institute of Complex Systems, Bioelectronics (ICS-8) , Forschungszentrum Jülich , 52428 Jülich , Germany
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23
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Clegg JR, Wagner AM, Shin SR, Hassan S, Khademhosseini A, Peppas NA. Modular Fabrication of Intelligent Material-Tissue Interfaces for Bioinspired and Biomimetic Devices. PROGRESS IN MATERIALS SCIENCE 2019; 106:100589. [PMID: 32189815 PMCID: PMC7079701 DOI: 10.1016/j.pmatsci.2019.100589] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
One of the goals of biomaterials science is to reverse engineer aspects of human and nonhuman physiology. Similar to the body's regulatory mechanisms, such devices must transduce changes in the physiological environment or the presence of an external stimulus into a detectable or therapeutic response. This review is a comprehensive evaluation and critical analysis of the design and fabrication of environmentally responsive cell-material constructs for bioinspired machinery and biomimetic devices. In a bottom-up analysis, we begin by reviewing fundamental principles that explain materials' responses to chemical gradients, biomarkers, electromagnetic fields, light, and temperature. Strategies for fabricating highly ordered assemblies of material components at the nano to macro-scales via directed assembly, lithography, 3D printing and 4D printing are also presented. We conclude with an account of contemporary material-tissue interfaces within bioinspired and biomimetic devices for peptide delivery, cancer theranostics, biomonitoring, neuroprosthetics, soft robotics, and biological machines.
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Affiliation(s)
- John R Clegg
- Department of Biomedical Engineering, the University of Texas at Austin, Austin, Texas, USA
| | - Angela M Wagner
- McKetta Department of Chemical Engineering, the University of Texas at Austin, Austin, Texas, USA
| | - Su Ryon Shin
- Division of Engineering in Medicine, Department of Medicine, Brigham Women's Hospital, Harvard Medical School, Cambridge, Massachusetts, USA
| | - Shabir Hassan
- Division of Engineering in Medicine, Department of Medicine, Brigham Women's Hospital, Harvard Medical School, Cambridge, Massachusetts, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ali Khademhosseini
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioindustrial Technologies, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea
| | - Nicholas A Peppas
- Department of Biomedical Engineering, the University of Texas at Austin, Austin, Texas, USA
- McKetta Department of Chemical Engineering, the University of Texas at Austin, Austin, Texas, USA
- Institute for Biomaterials, Drug Delivery, and Regenerative Medicine, the University of Texas at Austin, Austin, Texas, USA
- Department of Surgery and Perioperative Care, Dell Medical School, the University of Texas at Austin, Austin, Texas, USA
- Department of Pediatrics, Dell Medical School, the University of Texas at Austin, Austin, Texas, USA
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, the University of Texas at Austin, Austin, Texas, USA
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24
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Bahmani Jalali H, Karatum O, Melikov R, Dikbas UM, Sadeghi S, Yildiz E, Dogru IB, Ozgun Eren G, Ergun C, Sahin A, Kavakli IH, Nizamoglu S. Biocompatible Quantum Funnels for Neural Photostimulation. NANO LETTERS 2019; 19:5975-5981. [PMID: 31398051 PMCID: PMC6805044 DOI: 10.1021/acs.nanolett.9b01697] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Neural photostimulation has high potential to understand the working principles of complex neural networks and develop novel therapeutic methods for neurological disorders. A key issue in the light-induced cell stimulation is the efficient conversion of light to bioelectrical stimuli. In photosynthetic systems developed in millions of years by nature, the absorbed energy by the photoabsorbers is transported via nonradiative energy transfer to the reaction centers. Inspired by these systems, neural interfaces based on biocompatible quantum funnels are developed that direct the photogenerated charge carriers toward the bionanojunction for effective photostimulation. Funnels are constructed with indium-based rainbow quantum dots that are assembled in a graded energy profile. Implementation of a quantum funnel enhances the generated photoelectrochemical current 215% per unit absorbance in comparison with ungraded energy profile in a wireless and free-standing mode and facilitates optical neuromodulation of a single cell. This study indicates that the control of charge transport at nanoscale can lead to unconventional and effective neural interfaces.
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Affiliation(s)
- Houman Bahmani Jalali
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Onuralp Karatum
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Rustamzhon Melikov
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Ugur Meric Dikbas
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Sadra Sadeghi
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Erdost Yildiz
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Itir Bakis Dogru
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Guncem Ozgun Eren
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Cagla Ergun
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Afsun Sahin
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
- Department
of Ophthalmology, Koç University
Medical School, Istanbul 34450, Turkey
| | - Ibrahim Halil Kavakli
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
| | - Sedat Nizamoglu
- Graduate School of Biomedical Science and Engineering, Department of Electrical
and Electronics Engineering, Department of Molecular Biology and Genetics, Graduate School of
Material Science and Engineering, Research Center for Translational Medicine, and Department of Chemical
and Biological Engineering, Koç University, Istanbul 34450, Turkey
- E-mail:
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25
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Gulino M, Kim D, Pané S, Santos SD, Pêgo AP. Tissue Response to Neural Implants: The Use of Model Systems Toward New Design Solutions of Implantable Microelectrodes. Front Neurosci 2019; 13:689. [PMID: 31333407 PMCID: PMC6624471 DOI: 10.3389/fnins.2019.00689] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 06/18/2019] [Indexed: 01/28/2023] Open
Abstract
The development of implantable neuroelectrodes is advancing rapidly as these tools are becoming increasingly ubiquitous in clinical practice, especially for the treatment of traumatic and neurodegenerative disorders. Electrodes have been exploited in a wide number of neural interface devices, such as deep brain stimulation, which is one of the most successful therapies with proven efficacy in the treatment of diseases like Parkinson or epilepsy. However, one of the main caveats related to the clinical application of electrodes is the nervous tissue response at the injury site, characterized by a cascade of inflammatory events, which culminate in chronic inflammation, and, in turn, result in the failure of the implant over extended periods of time. To overcome current limitations of the most widespread macroelectrode based systems, new design strategies and the development of innovative materials with superior biocompatibility characteristics are currently being investigated. This review describes the current state of the art of in vitro, ex vivo, and in vivo models available for the study of neural tissue response to implantable microelectrodes. We particularly highlight new models with increased complexity that closely mimic in vivo scenarios and that can serve as promising alternatives to animal studies for investigation of microelectrodes in neural tissues. Additionally, we also express our view on the impact of the progress in the field of neural tissue engineering on neural implant research.
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Affiliation(s)
- Maurizio Gulino
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
- FEUP – Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
| | - Donghoon Kim
- Multi-Scale Robotics Lab (MSRL), Institute of Robotics and Intelligent Systems (IRIS), ETH Zurich, Zurich, Switzerland
| | - Salvador Pané
- Multi-Scale Robotics Lab (MSRL), Institute of Robotics and Intelligent Systems (IRIS), ETH Zurich, Zurich, Switzerland
| | - Sofia Duque Santos
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
| | - Ana Paula Pêgo
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
- FEUP – Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
- ICBAS – Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
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26
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Li W, Lin J, Wang T, Huang P. Photo-triggered Drug Delivery Systems for Neuron-related Applications. Curr Med Chem 2019; 26:1406-1422. [PMID: 29932026 DOI: 10.2174/0929867325666180622121801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 04/09/2018] [Accepted: 04/18/2018] [Indexed: 12/11/2022]
Abstract
The development of materials, chemistry and genetics has created a great number of systems for delivering antibiotics, neuropeptides or other drugs to neurons in neuroscience research, and has also provided important and powerful tools in neuron-related applications. Although these drug delivery systems can facilitate the advancement of neuroscience studies, they still have limited applications due to various drawbacks, such as difficulty in controlling delivery molecules or drugs to the target region, and trouble of releasing them in predictable manners. The combination of optics and drug delivery systems has great potentials to address these issues and deliver molecules or drugs to the nervous system with extraordinary spatiotemporal selectivity triggered by light. In this review, we will introduce the development of photo-triggered drug delivery systems in neuroscience research and their neuron-related applications including regulating neural activities, treating neural diseases and inducing nerve regenerations.
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Affiliation(s)
- Wei Li
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Laboratory of Evolutionary Theranostics, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China.,School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta GA 30332, United States
| | - Jing Lin
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Laboratory of Evolutionary Theranostics, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
| | - Tianfu Wang
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Laboratory of Evolutionary Theranostics, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
| | - Peng Huang
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Laboratory of Evolutionary Theranostics, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
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27
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Khoyratee F, Grassia F, Saïghi S, Levi T. Optimized Real-Time Biomimetic Neural Network on FPGA for Bio-hybridization. Front Neurosci 2019; 13:377. [PMID: 31068781 PMCID: PMC6491680 DOI: 10.3389/fnins.2019.00377] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 04/02/2019] [Indexed: 01/04/2023] Open
Abstract
Neurological diseases can be studied by performing bio-hybrid experiments using a real-time biomimetic Spiking Neural Network (SNN) platform. The Hodgkin-Huxley model offers a set of equations including biophysical parameters which can serve as a base to represent different classes of neurons and affected cells. Also, connecting the artificial neurons to the biological cells would allow us to understand the effect of the SNN stimulation using different parameters on nerve cells. Thus, designing a real-time SNN could useful for the study of simulations of some part of the brain. Here, we present a different approach to optimize the Hodgkin-Huxley equations adapted for Field Programmable Gate Array (FPGA) implementation. The equations of the conductance have been unified to allow the use of same functions with different parameters for all ionic channels. The low resources and high-speed implementation also include features, such as synaptic noise using the Ornstein-Uhlenbeck process and different synapse receptors including AMPA, GABAa, GABAb, and NMDA receptors. The platform allows real-time modification of the neuron parameters and can output different cortical neuron families like Fast Spiking (FS), Regular Spiking (RS), Intrinsically Bursting (IB), and Low Threshold Spiking (LTS) neurons using a Digital to Analog Converter (DAC). Gaussian distribution of the synaptic noise highlights similarities with the biological noise. Also, cross-correlation between the implementation and the model shows strong correlations, and bifurcation analysis reproduces similar behavior compared to the original Hodgkin-Huxley model. The implementation of one core of calculation uses 3% of resources of the FPGA and computes in real-time 500 neurons with 25,000 synapses and synaptic noise which can be scaled up to 15,000 using all resources. This is the first step toward neuromorphic system which can be used for the simulation of bio-hybridization and for the study of neurological disorders or the advanced research on neuroprosthesis to regain lost function.
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Affiliation(s)
- Farad Khoyratee
- Laboratoire de l'Intégration du Matériau au Système, Bordeaux INP, CNRS UMR 5218, University of Bordeaux, Talence, France
| | - Filippo Grassia
- LTI Laboratory, EA 3899, University of Picardie Jules Verne, Amiens, France
| | - Sylvain Saïghi
- Laboratoire de l'Intégration du Matériau au Système, Bordeaux INP, CNRS UMR 5218, University of Bordeaux, Talence, France
| | - Timothée Levi
- Laboratoire de l'Intégration du Matériau au Système, Bordeaux INP, CNRS UMR 5218, University of Bordeaux, Talence, France.,Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
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28
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Abstract
Substrate-integrated multielectrode arrays (MEAs) enable multisite, long-term, and label-free sensing and actuation of neuronal electrical signals in reduced cell culture models for network electrophysiology. Conventional, thin-film fabricated passive MEAs typically provide a few tens of electrode sites. New generations of active CMOS-based high-resolution arrays provide the capabilities of simultaneous recordings from thousands of neurons over fields of view of several square millimeters, yet allowing extracellular electrical imaging to be achieved down to the subcellular scale. In turn, such advancement in chip-based electrical readouts can significantly complement recently developed biotechnological and bimolecular techniques for neurobiology applications. Here, we describe (1) a simple method to fabricate passive MEAs and (2) protocols for preparing and growing primary rat hippocampal neuronal cultures and human iPS-derived neurons on MEAs. The aim is to provide reliable protocols for initiating the reader to this technology and for stimulating their further development and experimental use in neurobiology.
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29
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Rastogi SK, Kalmykov A, Johnson N, Cohen-Karni T. Bioelectronics with nanocarbons. J Mater Chem B 2018; 6:7159-7178. [PMID: 32254631 DOI: 10.1039/c8tb01600c] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Characterizing the electrical activity of cardiomyocytes and neurons is crucial in understanding the complex processes in the heart and brain tissues, both in healthy and diseased states. Micro- and nanotechnologies have significantly improved the electrophysiological investigation of cellular networks. Carbon-based nanomaterials or nanocarbons, such as carbon nanotubes (CNTs), nanodiamonds (NDs) and graphene are promising building blocks for bioelectronics platforms owing to their outstanding chemical and physical properties. In this review, we discuss the various bioelectronics applications of nanocarbons and their derivatives. Furthermore, we touch upon the challenges that remain in the field and describe the emergence of carbon-based hybrid-nanomaterials that will potentially address those limitations, thus improving the capabilities to investigate the electrophysiology of excitable cells, both as a network and at the single cell level.
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Affiliation(s)
- Sahil Kumar Rastogi
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
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30
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Abedini M, Tekieh T, Sasanpour P. Recording Neural Activity Based on Surface Plasmon Resonance by Optical Fibers-A Computational Analysis. Front Comput Neurosci 2018; 12:61. [PMID: 30123119 PMCID: PMC6085840 DOI: 10.3389/fncom.2018.00061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 07/11/2018] [Indexed: 02/05/2023] Open
Abstract
An all optical, non-destructive method for monitoring neural activity has been proposed and its performance in detection has been analyzed computationally. The proposed method is based on excitation of Surface Plasmon Resonance (SPR) through the structure of optical fibers. The sensor structure consists of a multimode optical fiber where, the cladding of fiber has been removed and thin film of gold structure has been deposited on the surface. Impinging the laser light with appropriate wavelength inside the fiber and based on the total internal reflection, the evanescent wave will excite surface plasmons in the gold thin film. The absorption of light by surface plasmons in the gold structure is severely dependent on the dielectric properties at its vicinity. The electrical activity of neural cells (action potential) can modulate the dielectric properties at its vicinity and hence can modify the absorption of light inside the optical fiber. We have computationally analyzed the performance of the proposed sensor with different available geometries using Finite Element Method (FEM). In this regard, we have shown that the optical response of proposed sensor will track the action potential of the neuron at its vicinity. Based on different geometrical structure, the sensor has absorption in different regions of visible spectrum.
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Affiliation(s)
- Mitra Abedini
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Shahid Beheshti Medical University, Tehran, Iran
| | - Tahereh Tekieh
- Complex System Group, Department of Physics, Sydney University, Sydney, NSW, Australia
| | - Pezhman Sasanpour
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Shahid Beheshti Medical University, Tehran, Iran.,School of Nanoscience, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
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31
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Characterization of a Novel Polypyrrole (PPy) Conductive Polymer Coated Patterned Vertical CNT (pvCNT) Dry ECG Electrode. CHEMOSENSORS 2018. [DOI: 10.3390/chemosensors6030027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Conventional electrode-based technologies, such as the electrocardiogram (ECG), capture physiological signals using an electrolyte solution or gel that evaporates shortly after exposure, resulting in a decrease in the quality of the signal. Previously, we reported a novel dry impedimetric electrode using patterned vertically-aligned Carbon NanoTubes (pvCNT) for biopotential measurement applications. The mechanical adhesion strength of the pvCNT electrode to the substrate was weak, hence, we have improved this electrode using a thin coating of the conductive polymer polypyrrole (PPy) that strengthens its mechanical properties. Multiwall CNTs were grown vertically on a circular stainless-steel disc (⌀ = 10 mm) substrate of 50 µm thickness forming patterned pillars on a square base (100 µm × 100 µm) with an inter-pillar spacing of 200 µm and height up to 1.5 mm. The PPy coating procedure involves applying 10 µL of PPy mixed with 70% ethyl alcohol solution and rapid drying at 300 °C using a hot air gun at a distance of 10 cm. A comparative study demonstrated that the coated pvCNT had higher impedance compared to a non-coated pvCNT but lower impedance compared to the standard gel electrode. The PPy-coated pvCNT had comparable signal capture quality but stronger mechanical adhesion to the substrate.
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32
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Abstract
Artificially activating neurons in the cortex can make a tetraplegic patient feel naturalistic sensations of skin pressure and arm movement.
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Affiliation(s)
- Victor de Lafuente
- Institute of NeurobiologyNational Autonomous University of MexicoQuerétaroMéxico
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33
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Visual Servoing-Based Nanorobotic System for Automated Electrical Characterization of Nanotubes inside SEM. SENSORS 2018; 18:s18041137. [PMID: 29642495 PMCID: PMC5948737 DOI: 10.3390/s18041137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 03/25/2018] [Accepted: 03/26/2018] [Indexed: 11/23/2022]
Abstract
The maneuvering and electrical characterization of nanotubes inside a scanning electron microscope (SEM) has historically been time-consuming and laborious for operators. Before the development of automated nanomanipulation-enabled techniques for the performance of pick-and-place and characterization of nanoobjects, these functions were still incomplete and largely operated manually. In this paper, a dual-probe nanomanipulation system vision-based feedback was demonstrated to automatically perform 3D nanomanipulation tasks, to investigate the electrical characterization of nanotubes. The XY-position of Atomic Force Microscope (AFM) cantilevers and individual carbon nanotubes (CNTs) were precisely recognized via a series of image processing operations. A coarse-to-fine positioning strategy in the Z-direction was applied through the combination of the sharpness-based depth estimation method and the contact-detection method. The use of nanorobotic magnification-regulated speed aided in improving working efficiency and reliability. Additionally, we proposed automated alignment of manipulator axes by visual tracking the movement trajectory of the end effector. The experimental results indicate the system’s capability for automated measurement electrical characterization of CNTs. Furthermore, the automated nanomanipulation system has the potential to be extended to other nanomanipulation tasks.
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34
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Cools J, Jin Q, Yoon E, Alba Burbano D, Luo Z, Cuypers D, Callewaert G, Braeken D, Gracias DH. A Micropatterned Multielectrode Shell for 3D Spatiotemporal Recording from Live Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1700731. [PMID: 29721420 PMCID: PMC5908352 DOI: 10.1002/advs.201700731] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 11/12/2017] [Indexed: 05/18/2023]
Abstract
Microelectrode arrays (MEAs) have proved to be useful tools for characterizing electrically active cells such as cardiomyocytes and neurons. While there exist a number of integrated electronic chips for recording from small populations or even single cells, they rely primarily on the interface between the cells and 2D flat electrodes. Here, an approach that utilizes residual stress-based self-folding to create individually addressable multielectrode interfaces that wrap around the cell in 3D and function as an electrical shell-like recording device is described. These devices are optically transparent, allowing for simultaneous fluorescence imaging. Cell viability is maintained during and after electrode wrapping around the cel and chemicals can diffuse into and out of the self-folding devices. It is further shown that 3D spatiotemporal recordings are possible and that the action potentials recorded from cultured neonatal rat ventricular cardiomyocytes display significantly higher signal-to-noise ratios in comparison with signals recorded with planar extracellular electrodes. It is anticipated that this device can provide the foundation for the development of new-generation MEAs where dynamic electrode-cell interfacing and recording substitutes the traditional method using static electrodes.
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Affiliation(s)
- Jordi Cools
- imec, Department of Life Sciences and ImagingKapeldreef 753001LeuvenBelgium
- KU Leuven, Department of Cellular and Molecular Medicine3000LeuvenBelgium
| | - Qianru Jin
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
| | - Eugene Yoon
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
| | - Diego Alba Burbano
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
| | - Zhenxiang Luo
- imec, Department of Life Sciences and ImagingKapeldreef 753001LeuvenBelgium
| | - Dieter Cuypers
- Centre for Microsystems Technology (CMST)Ghent University and imecTechnologiepark – Zwijnaarde 159052GentBelgium
| | - Geert Callewaert
- KU Leuven, Department of Cellular and Molecular Medicine3000LeuvenBelgium
| | - Dries Braeken
- imec, Department of Life Sciences and ImagingKapeldreef 753001LeuvenBelgium
| | - David H. Gracias
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
- Department of Materials Science and EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
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35
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Lo MC, Wang S, Singh S, Damodaran VB, Ahmed I, Coffey K, Barker D, Saste K, Kals K, Kaplan HM, Kohn J, Shreiber DI, Zahn JD. Evaluating the in vivo glial response to miniaturized parylene cortical probes coated with an ultra-fast degrading polymer to aid insertion. J Neural Eng 2018; 15:036002. [PMID: 29485103 DOI: 10.1088/1741-2552/aa9fad] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Despite the feasibility of short-term neural recordings using implantable microelectrodes, attaining reliable, chronic recordings remains a challenge. Most neural recording devices suffer from a long-term tissue response, including gliosis, at the device-tissue interface. It was hypothesized that smaller, more flexible intracortical probes would limit gliosis by providing a better mechanical match with surrounding tissue. APPROACH This paper describes the in vivo evaluation of flexible parylene microprobes designed to improve the interface with the adjacent neural tissue to limit gliosis and thereby allow for improved recording longevity. The probes were coated with an ultrafast degrading tyrosine-derived polycarbonate (E5005(2K)) polymer that provides temporary mechanical support for device implantation, yet degrades within 2 h post-implantation. A parametric study of probes of varying dimensions and polymer coating thicknesses were implanted in rat brains. The glial tissue response and neuronal loss were assessed from 72 h to 24 weeks post-implantation via immunohistochemistry. MAIN RESULTS Experimental results suggest that both probe and polymer coating sizes affect the extent of gliosis. When an appropriate sized coating dimension (100 µm × 100 µm) and small probe (30 µm × 5 µm) was implanted, a minimal post-implantation glial response was observed. No discernible gliosis was detected when compared to tissue where a sham control consisting of a solid degradable polymer shuttle of the same dimensions was inserted. A larger polymer coating (200 µm × 200 µm) device induced a more severe glial response at later time points, suggesting that the initial insertion trauma can affect gliosis even when the polymer shuttle degrades rapidly. A larger degree of gliosis was also observed when comparing a larger sized probe (80 µm × 5 µm) to a smaller probe (30 µm × 5 µm) using the same polymer coating size (100 µm × 100 µm). There was no significant neuronal loss around the implantation sites for most device candidates except the group with largest polymer coating and probe sizes. SIGNIFICANCE These results suggest that: (1) the degree of mechanical trauma at device implantation and mechanical mismatches at the probe-tissue interface affect long term gliosis; (2) smaller, more flexible probes may minimize the glial response to provide improved tissue biocompatibility when used for chronic neural signal recording; and (3) some degree of glial scarring did not significantly affect neuronal distribution around the probe.
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Affiliation(s)
- Meng-Chen Lo
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, United States of America
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36
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A biopotential optrode array: operation principles and simulations. Sci Rep 2018; 8:2690. [PMID: 29426924 PMCID: PMC5807498 DOI: 10.1038/s41598-018-20182-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/21/2017] [Indexed: 01/11/2023] Open
Abstract
We propose an optical electrode ’optrode’ sensor array for biopotential measurements. The transduction mechanism is based on deformed helix ferroelectric liquid crystals which realign, altering the optrode’s light reflectance properties, relative to applied potential fields of biological cells and tissue. A computational model of extracellular potential recording by the optrode including the electro-optical transduction mechanism is presented, using a combination of time-domain and frequency-domain finite element analysis. Simulations indicate that the device has appropriate temporal response to faithfully transduce neuronal spikes, and spatial resolution to capture impulse propagation along a single neuron. These simulations contribute to the development of multi-channel optrode arrays for spatio-temporal mapping of electric events in excitable biological tissue.
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37
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Nagamine K, Sato H, Kai H, Kaji H, Kanzaki M, Nishizawa M. Contractile Skeletal Muscle Cells Cultured with a Conducting Soft Wire for Effective, Selective Stimulation. Sci Rep 2018; 8:2253. [PMID: 29396483 PMCID: PMC5797109 DOI: 10.1038/s41598-018-20729-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 01/23/2018] [Indexed: 01/04/2023] Open
Abstract
Contractile skeletal muscle cells were cultured so as to wrap around an electrode wire to enable their selective stimulation even when they were co-cultured with other electrically-excitable cells. Since the electrode wire was composed of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and polyurethane (PU), which is soft and highly capacitive (~10 mF cm-2), non-faradaic electrical stimulation with charge/discharge currents could be applied to the surrounding cells without causing significant damage even for longer periods (more than a week). The advantage of this new culture system was demonstrated in the study of chemotactic interaction of monocytes and skeletal muscle cells via myokines.
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Affiliation(s)
- Kuniaki Nagamine
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Hirotaka Sato
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Hiroyuki Kai
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Hirokazu Kaji
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Makoto Kanzaki
- Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, 6-6-04 Aoba-ku, Sendai, 980-8579, Japan
| | - Matsuhiko Nishizawa
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan.
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Cruttenden CE, Taylor JM, Hu S, Zhang Y, Zhu XH, Chen W, Rajamani R. Carbon Nano-Structured Neural Probes Show Promise for Magnetic Resonance Imaging Applications. Biomed Phys Eng Express 2017; 4. [PMID: 29623217 DOI: 10.1088/2057-1976/aa948d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Objective Previous animal studies have demonstrated that carbon nanotube (CNT) electrodes provide several advantages of preferential cell growth and better signal-to-noise ratio when interfacing with brain neural tissue. This work explores another advantage of CNT electrodes, namely their MRI compatibility. MRI-compatible neural electrodes that do not produce image artifacts will allow simultaneous co-located functional MRI and neural signal recordings, which will help improve our understanding of the brain. Approach Prototype CNT electrodes on polyimide substrates are fabricated and tested in vitro and in vivo in rat brain at 9.4T. To understand the results of the in vitro and in vivo studies, a simulation model based on numerical computation of the magnetic field around a two-dimensional object in a tissue substrate is developed. Main Results The prototype electrodes are found to introduce negligible image artifacts in structural and functional imaging sequences in vitro and in vivo. Simulation results confirm that CNT prototype electrodes produce less magnetic field distortion than traditional metallic electrodes due to a combination of both superior material properties and geometry. By using CNT films, image artifacts can be nearly eliminated at magnetic fields of strength up to 9.4T. At the same time, the high surface area of a CNT film provides high charge transfer and enables neural local field potential (LFP) recordings with an equal or better signal-to-noise ratio (SNR) than traditional electrodes. Significance CNT film electrodes can be used for simultaneous MRI and electrophysiology in animal models to investigate fundamental neuroscience questions and clinically relevant topics such as epilepsy.
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Affiliation(s)
- Corey E Cruttenden
- Department of Mechanical Engineering, University of Minnesota, 111 Church St. SE, Minneapolis, MN
| | - Jennifer M Taylor
- Department of Biomedical Engineering, University of Minnesota, 312 Church St. SE, Minneapolis, MN.,Center for Magnetic Resonance Research, University of Minnesota, 2021 6 St. SE, Minneapolis, MN
| | - Shan Hu
- Department of Mechanical Engineering, Iowa State University, 2025 Black Engineering, Ames, IA
| | - Yi Zhang
- Center for Magnetic Resonance Research, University of Minnesota, 2021 6 St. SE, Minneapolis, MN
| | - Xiao-Hong Zhu
- Center for Magnetic Resonance Research, University of Minnesota, 2021 6 St. SE, Minneapolis, MN
| | - Wei Chen
- Department of Biomedical Engineering, University of Minnesota, 312 Church St. SE, Minneapolis, MN.,Center for Magnetic Resonance Research, University of Minnesota, 2021 6 St. SE, Minneapolis, MN
| | - Rajesh Rajamani
- Department of Mechanical Engineering, University of Minnesota, 111 Church St. SE, Minneapolis, MN
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Barriga-Rivera A, Bareket L, Goding J, Aregueta-Robles UA, Suaning GJ. Visual Prosthesis: Interfacing Stimulating Electrodes with Retinal Neurons to Restore Vision. Front Neurosci 2017; 11:620. [PMID: 29184478 PMCID: PMC5694472 DOI: 10.3389/fnins.2017.00620] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/23/2017] [Indexed: 01/06/2023] Open
Abstract
The bypassing of degenerated photoreceptors using retinal neurostimulators is helping the blind to recover functional vision. Researchers are investigating new ways to improve visual percepts elicited by these means as the vision produced by these early devices remain rudimentary. However, several factors are hampering the progression of bionic technologies: the charge injection limits of metallic electrodes, the mechanical mismatch between excitable tissue and the stimulating elements, neural and electric crosstalk, the physical size of the implanted devices, and the inability to selectively activate different types of retinal neurons. Electrochemical and mechanical limitations are being addressed by the application of electromaterials such as conducting polymers, carbon nanotubes and nanocrystalline diamonds, among other biomaterials, to electrical neuromodulation. In addition, the use of synthetic hydrogels and cell-laden biomaterials is promising better interfaces, as it opens a door to establishing synaptic connections between the electrode material and the excitable cells. Finally, new electrostimulation approaches relying on the use of high-frequency stimulation and field overlapping techniques are being developed to better replicate the neural code of the retina. All these elements combined will bring bionic vision beyond its present state and into the realm of a viable, mainstream therapy for vision loss.
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Affiliation(s)
- Alejandro Barriga-Rivera
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
- Faculty of Engineering and Information Technologies, University of Sydney, Sydney, NSW, Australia
- Division of Neuroscience, University Pablo de Olavide, Sevilla, Spain
| | - Lilach Bareket
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
- Faculty of Engineering and Information Technologies, University of Sydney, Sydney, NSW, Australia
| | - Josef Goding
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | | | - Gregg J. Suaning
- Faculty of Engineering and Information Technologies, University of Sydney, Sydney, NSW, Australia
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Unraveling the mechanistic effects of electric field stimulation towards directing stem cell fate and function: A tissue engineering perspective. Biomaterials 2017; 150:60-86. [PMID: 29032331 DOI: 10.1016/j.biomaterials.2017.10.003] [Citation(s) in RCA: 194] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 09/27/2017] [Accepted: 10/02/2017] [Indexed: 02/06/2023]
Abstract
Electric field (EF) stimulation can play a vital role in eliciting appropriate stem cell response. Such an approach is recently being established to guide stem cell differentiation through osteogenesis/neurogenesis/cardiomyogenesis. Despite significant recent efforts, the biophysical mechanisms by which stem cells sense, interpret and transform electrical cues into biochemical and biological signals still remain unclear. The present review critically analyses the variety of EF stimulation approaches that can be employed to evoke appropriate stem cell response and also makes an attempt to summarize the underlying concepts of this notion, placing special emphasis on stem cell based tissue engineering and regenerative medicine. This review also discusses the major signaling pathways and cellular responses that are elicited by electric stimulation, including the participation of reactive oxygen species and heat shock proteins, modulation of intracellular calcium ion concentration, ATP production and numerous other events involving the clustering or reassembling of cell surface receptors, cytoskeletal remodeling and so on. The specific advantages of using external electric stimulation in different modalities to regulate stem cell fate processes are highlighted with explicit examples, in vitro and in vivo.
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Schneider JJ. Vertically Aligned Carbon Nanotubes as Platform for Biomimetically Inspired Mechanical Sensing, Bioactive Surfaces, and Electrical Cell Interfacing. ACTA ACUST UNITED AC 2017; 1:e1700101. [PMID: 32646166 DOI: 10.1002/adbi.201700101] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/04/2017] [Indexed: 12/30/2022]
Abstract
Vertically aligned carbon nanotubes (VACNTs) are one dimensional carbon objects anchored atop of a solid substrate. They are geometrically fixed in contrast to their counterparts, randomly oriented carbon nanotubes (CNTs). In this progress report, the breadth in which these one dimensional, mechanically flexible, though robust and electrical conducting carbon nanostructures can be employed as functional material is shown and our research is put in perspective to work in the last five to ten years. The connection between the different areas touched in this report is the biomimetic-materials approach, which rely on the hairy morphology of VACNTs. These properties in connection with their electrical conductivity offer possibilities towards new functional features and applications of VACNTs. To appreciate the possibilities of biomimetic research with VACNTs, first their material characteristics are given to make the reader familiar with specific features of their synthesis, the peculiarities in arranging and controlling the morphology of CNTs in a vertical alignment as well as a current understanding of these properties on a microscopic basis. In doing so, similarities as well as differences, which offer new possibilities for biomimetic studies of VACNTS with respect to multiwalled randomly oriented CNTs, will become clear.
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Affiliation(s)
- Jörg J Schneider
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss Str. 12, 64287, Darmstadt, Germany
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Weidlich S, Krause KJ, Schnitker J, Wolfrum B, Offenhäusser A. MEAs and 3D nanoelectrodes: electrodeposition as tool for a precisely controlled nanofabrication. NANOTECHNOLOGY 2017; 28:095302. [PMID: 28139471 DOI: 10.1088/1361-6528/aa57b5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Microelectrode arrays (MEAs) are gaining increasing importance for the investigation of signaling processes between electrogenic cells. However, efficient cell-chip coupling for robust and long-term electrophysiological recording and stimulation still remains a challenge. A possible approach for the improvement of the cell-electrode contact is the utilization of three-dimensional structures. In recent years, various 3D electrode geometries have been developed, but we are still lacking a fabrication approach that enables the formation of different 3D structures on a single chip in a controlled manner. This, however, is needed to enable a direct and reliable comparison of the recording capabilities of the different structures. Here, we present a method for a precisely controlled deposition of nanoelectrodes, enabling the fabrication of multiple, well-defined types of structures on our 64 electrode MEAs towards a rapid-prototyping approach to 3D electrodes.
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Affiliation(s)
- Sabrina Weidlich
- Institute of Bioelectronics (ICS-8/PGI-8), Forschungszentrum Jülich, D-52428 Jülich, Germany
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43
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Jeong DW, Kim GH, Kim NY, Lee Z, Jung SD, Lee JO. A high-performance transparent graphene/vertically aligned carbon nanotube (VACNT) hybrid electrode for neural interfacing. RSC Adv 2017. [DOI: 10.1039/c6ra26836f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Transparent graphene-vertically aligned carbon nanotube (VACNT) electrodes enable the dual function of optical cell monitoring and cell electrical signal measurements with exceptionally high signal amplitude.
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Affiliation(s)
- Du Won Jeong
- Advanced Materials Division
- Korea Research Institute of Chemical Technology (KRICT)
- Daejeon 34114
- Korea
| | - Gook Hwa Kim
- Synapse Device Creative Research Section
- Electronics and Telecommunications Research Institute (ETRI)
- Daejeon 34129
- Korea
| | - Na Yeon Kim
- School of Materials Science and Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Korea
| | - Zonghoon Lee
- School of Materials Science and Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Korea
| | - Sang Don Jung
- Synapse Device Creative Research Section
- Electronics and Telecommunications Research Institute (ETRI)
- Daejeon 34129
- Korea
| | - Jeong-O. Lee
- Advanced Materials Division
- Korea Research Institute of Chemical Technology (KRICT)
- Daejeon 34114
- Korea
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Versatile Flexible Graphene Multielectrode Arrays. BIOSENSORS-BASEL 2016; 7:bios7010001. [PMID: 28025564 PMCID: PMC5371774 DOI: 10.3390/bios7010001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 11/25/2016] [Accepted: 12/14/2016] [Indexed: 01/13/2023]
Abstract
Graphene is a promising material possessing features relevant to bioelectronics applications. Graphene microelectrodes (GMEAs), which are fabricated in a dense array on a flexible polyimide substrate, were investigated in this work for their performance via electrical impedance spectroscopy. Biocompatibility and suitability of the GMEAs for extracellular recordings were tested by measuring electrical activities from acute heart tissue and cardiac muscle cells. The recordings show encouraging signal-to-noise ratios of 65 ± 15 for heart tissue recordings and 20 ± 10 for HL-1 cells. Considering the low noise and excellent robustness of the devices, the sensor arrays are suitable for diverse and biologically relevant applications.
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45
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Eleftheriou CG, Zimmermann JB, Kjeldsen HD, David-Pur M, Hanein Y, Sernagor E. Carbon nanotube electrodes for retinal implants: A study of structural and functional integration over time. Biomaterials 2016; 112:108-121. [PMID: 27760395 PMCID: PMC5123641 DOI: 10.1016/j.biomaterials.2016.10.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 10/08/2016] [Accepted: 10/11/2016] [Indexed: 12/15/2022]
Abstract
The choice of electrode material is of paramount importance in neural prosthetic devices. Electrodes must be biocompatible yet able to sustain repetitive current injections in a highly corrosive environment. We explored the suitability of carbon nanotube (CNT) electrodes to stimulate retinal ganglion cells (RGCs) in a mouse model of outer retinal degeneration. We investigated morphological changes at the bio-hybrid interface and changes in RGC responses to electrical stimulation following prolonged in vitro coupling to CNT electrodes. We observed gradual remodelling of the inner retina to incorporate CNT assemblies. Electrophysiological recordings demonstrate a progressive increase in coupling between RGCs and the CNT electrodes over three days, characterized by a gradual decrease in stimulation thresholds and increase in cellular recruitment. These results provide novel evidence for time-dependent formation of viable bio-hybrids between CNTs and the retina, demonstrating that CNTs are a promising material for inclusion in retinal prosthetic devices.
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Affiliation(s)
- Cyril G Eleftheriou
- Institute of Neuroscience, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, United Kingdom
| | - Jonas B Zimmermann
- Institute of Neuroscience, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, United Kingdom
| | - Henrik D Kjeldsen
- Institute of Neuroscience, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, United Kingdom
| | - Moshe David-Pur
- School of Electrical Engineering, Tel-Aviv University, Ramat-Aviv, Tel-Aviv, 69978, Israel
| | - Yael Hanein
- School of Electrical Engineering, Tel-Aviv University, Ramat-Aviv, Tel-Aviv, 69978, Israel
| | - Evelyne Sernagor
- Institute of Neuroscience, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, United Kingdom.
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Burblies N, Schulze J, Schwarz HC, Kranz K, Motz D, Vogt C, Lenarz T, Warnecke A, Behrens P. Coatings of Different Carbon Nanotubes on Platinum Electrodes for Neuronal Devices: Preparation, Cytocompatibility and Interaction with Spiral Ganglion Cells. PLoS One 2016; 11:e0158571. [PMID: 27385031 PMCID: PMC4934701 DOI: 10.1371/journal.pone.0158571] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 06/18/2016] [Indexed: 12/28/2022] Open
Abstract
Cochlear and deep brain implants are prominent examples for neuronal prostheses with clinical relevance. Current research focuses on the improvement of the long-term functionality and the size reduction of neural interface electrodes. A promising approach is the application of carbon nanotubes (CNTs), either as pure electrodes but especially as coating material for electrodes. The interaction of CNTs with neuronal cells has shown promising results in various studies, but these appear to depend on the specific type of neurons as well as on the kind of nanotubes. To evaluate a potential application of carbon nanotube coatings for cochlear electrodes, it is necessary to investigate the cytocompatibility of carbon nanotube coatings on platinum for the specific type of neuron in the inner ear, namely spiral ganglion neurons. In this study we have combined the chemical processing of as-delivered CNTs, the fabrication of coatings on platinum, and the characterization of the electrical properties of the coatings as well as a general cytocompatibility testing and the first cell culture investigations of CNTs with spiral ganglion neurons. By applying a modification process to three different as-received CNTs via a reflux treatment with nitric acid, long-term stable aqueous CNT dispersions free of dispersing agents were obtained. These were used to coat platinum substrates by an automated spray-coating process. These coatings enhance the electrical properties of platinum electrodes, decreasing the impedance values and raising the capacitances. Cell culture investigations of the different CNT coatings on platinum with NIH3T3 fibroblasts attest an overall good cytocompatibility of these coatings. For spiral ganglion neurons, this can also be observed but a desired positive effect of the CNTs on the neurons is absent. Furthermore, we found that the well-established DAPI staining assay does not function on the coatings prepared from single-wall nanotubes.
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Affiliation(s)
- Niklas Burblies
- Institute for Inorganic Chemistry, Leibniz University Hannover, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
| | - Jennifer Schulze
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
| | - Hans-Christoph Schwarz
- Institute for Inorganic Chemistry, Leibniz University Hannover, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
| | - Katharina Kranz
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
| | - Damian Motz
- Institute for Inorganic Chemistry, Leibniz University Hannover, Hanover, Germany
| | - Carla Vogt
- Institute for Inorganic Chemistry, Leibniz University Hannover, Hanover, Germany
| | - Thomas Lenarz
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
| | - Athanasia Warnecke
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
| | - Peter Behrens
- Institute for Inorganic Chemistry, Leibniz University Hannover, Hanover, Germany
- Cluster of Excellence Hearing4all, Hanover, Germany
- * E-mail:
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Scapin G, Bertalot T, Vicentini N, Gatti T, Tescari S, De Filippis V, Marega C, Menna E, Gasparella M, Parnigotto PP, Di Liddo R, Filippini F. Neuronal commitment of human circulating multipotent cells by carbon nanotube-polymer scaffolds and biomimetic peptides. Nanomedicine (Lond) 2016; 11:1929-46. [PMID: 27246559 DOI: 10.2217/nnm-2016-0150] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
AIM We aimed to set up a self-standing, biomimetic scaffold system able to induce and support per se neuronal differentiation of autologous multipotent cells. MATERIALS & METHODS We isolated a population of human circulating multipotent cells (hCMCs), and used carbon nanotube/polymer nanocomposite scaffolds to mimic electrical/nanotopographical features of the neural environment, and biomimetic peptides reproducing axon guidance cues from neural proteins. RESULTS hCMCs showed high degree of stemness and multidifferentiative potential; stimuli from the scaffolds and biomimetic peptides could induce and boost hCMC differentiation toward neuronal lineage despite the absence of exogenously added, specific growth factors. CONCLUSION This work suggests the scaffold-peptides system combined with autologous hCMCs as a functional biomimetic, self-standing prototype for neural regenerative medicine applications.
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Affiliation(s)
- Giorgia Scapin
- Department of Biology, University of Padua, 35131 Padua, Italy
| | - Thomas Bertalot
- Department of Pharmaceutical & Pharmacological Sciences, University of Padua, 35131 Padua, Italy
| | - Nicola Vicentini
- Department of Chemical Sciences, University of Padua, 35131 Padua, Italy
| | - Teresa Gatti
- Department of Chemical Sciences, University of Padua, 35131 Padua, Italy
| | - Simone Tescari
- Department of Pharmaceutical & Pharmacological Sciences, University of Padua, 35131 Padua, Italy
| | - Vincenzo De Filippis
- Department of Pharmaceutical & Pharmacological Sciences, University of Padua, 35131 Padua, Italy
| | - Carla Marega
- Department of Chemical Sciences, University of Padua, 35131 Padua, Italy
| | - Enzo Menna
- Department of Chemical Sciences, University of Padua, 35131 Padua, Italy
| | - Marco Gasparella
- Department of Woman & Child Health, University of Padua, 35128 Padua, Italy
| | - Pier Paolo Parnigotto
- Tissue Engineering & Signaling ONLUS, Caselle di Selvazzano Dentro, 35030 Padua, Italy
| | - Rosa Di Liddo
- Department of Pharmaceutical & Pharmacological Sciences, University of Padua, 35131 Padua, Italy
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Yamada A, Vignes M, Bureau C, Mamane A, Venzac B, Descroix S, Viovy JL, Villard C, Peyrin JM, Malaquin L. In-mold patterning and actionable axo-somatic compartmentalization for on-chip neuron culture. LAB ON A CHIP 2016; 16:2059-68. [PMID: 27170212 DOI: 10.1039/c6lc00414h] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Oriented neuronal networks with controlled connectivity are required for many applications ranging from studies of neurodegeneration to neuronal computation. To build such networks in vitro, an efficient, directed and long lasting guidance of axons toward their target is a pre-requisite. The best guidance achieved so far, however, relies on confining axons in enclosed microchannels, making them poorly accessible for further investigation. Here we describe a method providing accessible and highly regular arrays of axons, emanating from somas positioned in distinct compartments. This method combines the use of a novel removable partition, allowing soma positioning outside of the axon guidance patterns, and in-mold patterning (iMP), a hybrid method combining chemical and mechanical cell positioning clues applied here for the first time to neurons. The axon guidance efficiency of iMP is compared to that of conventional patterning methods, e.g. micro-contact printing (chemical constraints by a poly-l-lysine motif) and micro-grooves (physical constraints by homogeneously coated microstructures), using guiding tracks of different widths and spacing. We show that iMP provides a gain of 10 to 100 in axon confinement efficiency on the tracks, yielding mm-long, highly regular, and fully accessible on-chip axon arrays. iMP also allows well-defined axon guidance from small populations of several neurons confined at predefined positions in μm-sized wells. iMP will thus open new routes for the construction of complex and accurately controlled neuronal networks.
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Affiliation(s)
- Ayako Yamada
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France
| | - Maéva Vignes
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France and UPMC Univ Paris 06, CNRS, UMR 8256, B2A, Sorbonne Universités, Biological Adaptation and Ageing, Institut de Biologie Paris Seine, Paris, F-75005, France. (JMP)
| | - Cécile Bureau
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France
| | - Alexandre Mamane
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France
| | - Bastien Venzac
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France
| | - Stéphanie Descroix
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France
| | - Jean-Louis Viovy
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France
| | - Catherine Villard
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France and CNRS, Inst NEEL and CRETA, Univ. Grenoble Alpes, F-38042 Grenoble, France
| | - Jean-Michel Peyrin
- UPMC Univ Paris 06, CNRS, UMR 8256, B2A, Sorbonne Universités, Biological Adaptation and Ageing, Institut de Biologie Paris Seine, Paris, F-75005, France. (JMP)
| | - Laurent Malaquin
- Institut Curie, PSL Research University, CNRS, UMR 168, F-75005, Paris, France. (CV) (LM) and Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 168, F-75005, Paris, France and LAAS-CNRS, Université de Toulouse, CNRS, Toulouse, France.
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Contreras ML, Villarroel I, Rozas R. Hydrogen physisorption energies for bumpy, saturated, nitrogen-doped single-walled carbon nanotubes. Struct Chem 2016. [DOI: 10.1007/s11224-016-0767-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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50
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Modeling the Insertion Mechanics of Flexible Neural Probes Coated with Sacrificial Polymers for Optimizing Probe Design. SENSORS 2016; 16:s16030330. [PMID: 26959021 PMCID: PMC4813905 DOI: 10.3390/s16030330] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/18/2016] [Accepted: 02/29/2016] [Indexed: 01/20/2023]
Abstract
Single-unit recording neural probes have significant advantages towards improving signal-to-noise ratio and specificity for signal acquisition in brain-to-computer interface devices. Long-term effectiveness is unfortunately limited by the chronic injury response, which has been linked to the mechanical mismatch between rigid probes and compliant brain tissue. Small, flexible microelectrodes may overcome this limitation, but insertion of these probes without buckling requires supporting elements such as a stiff coating with a biodegradable polymer. For these coated probes, there is a design trade-off between the potential for successful insertion into brain tissue and the degree of trauma generated by the insertion. The objective of this study was to develop and validate a finite element model (FEM) to simulate insertion of coated neural probes of varying dimensions and material properties into brain tissue. Simulations were performed to predict the buckling and insertion forces during insertion of coated probes into a tissue phantom with material properties of brain. The simulations were validated with parallel experimental studies where probes were inserted into agarose tissue phantom, ex vivo chick embryonic brain tissue, and ex vivo rat brain tissue. Experiments were performed with uncoated copper wire and both uncoated and coated SU-8 photoresist and Parylene C probes. Model predictions were found to strongly agree with experimental results (<10% error). The ratio of the predicted buckling force-to-predicted insertion force, where a value greater than one would ideally be expected to result in successful insertion, was plotted against the actual success rate from experiments. A sigmoidal relationship was observed, with a ratio of 1.35 corresponding to equal probability of insertion and failure, and a ratio of 3.5 corresponding to a 100% success rate. This ratio was dubbed the “safety factor”, as it indicated the degree to which the coating should be over-designed to ensure successful insertion. Probability color maps were generated to visually compare the influence of design parameters. Statistical metrics derived from the color maps and multi-variable regression analysis confirmed that coating thickness and probe length were the most important features in influencing insertion potential. The model also revealed the effects of manufacturing flaws on insertion potential.
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