1
|
Niederhoffer T, Vanhoestenberghe A, Lancashire HT. Extending the understanding of Shannon's safe stimulation limit for platinum electrodes: biphasic charge-balanced pulse trains in unbuffered saline at pH = 1 to pH = 12. J Neural Eng 2024; 21:056007. [PMID: 38579740 DOI: 10.1088/1741-2552/ad3b6a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Accepted: 04/05/2024] [Indexed: 04/07/2024]
Abstract
Objective.In neural electrical stimulation, safe stimulation guidelines are essential to deliver efficient treatment while avoiding neural damage and electrode degradation. The widely used Shannon's limit,k, gives conditions on the stimulation parameters to avoid neural damage, however, underlying damage mechanisms are not fully understood. Moreover, the translation from bench testing toin vivoexperiments still presents some challenges, including the increased polarisation observed, which may influence charge-injection mechanisms. In this work, we studied the influence on damage mechanisms of two electrolyte parameters that are differentin vivocompared to usual bench tests: solution pH and electrolyte gelation.Approach.The potential of a platinum macroelectrode was monitored in a three-electrode setup during current-controlled biphasic charge-balanced cathodic-first pulse trains. Maximum anodic and cathodic potential excursions during pulse trains were projected on cyclic voltammograms to infer possible electrochemical reactions.Main results.In unbuffered saline of pH ranging from 1 to 12, the maximum anodic potential was systematically located in the oxide formation region, while the cathodic potential was located the molecular oxygen and oxide reduction region whenkapproached Shannon's damage limit, independent of solution pH. The results support the hypothesis that Shannon's limit corresponds to the beginning of platinum dissolution following repeated cycles of platinum oxidation and reduction, for which the cathodic excursion is a key tipping point. Despite similar potential excursions between solution and gel electrolytes, we found a joint influence of pH and gelation on the cathodic potential alone, while we observed no effect on the anodic potential. We hypothesise that gelation creates a positive feedback loop exacerbating the effects of pH ; however, the extent of that influence needs to be examined further.Significance.This work supports the hypothesis of charge injection mechanisms associated with stimulation-induced damage at platinum electrodes. The validity of a major hypothesis explaining stimulation-induced damage was tested and supported on a range of electrolytes representing potential electrode environments, calling for further characterisation of platinum dissolution during electrical stimulation in various testing conditions.
Collapse
Affiliation(s)
- Thomas Niederhoffer
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, United Kingdom
| | - Anne Vanhoestenberghe
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Henry T Lancashire
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, United Kingdom
| |
Collapse
|
2
|
Chang S, Koo JH, Yoo J, Kim MS, Choi MK, Kim DH, Song YM. Flexible and Stretchable Light-Emitting Diodes and Photodetectors for Human-Centric Optoelectronics. Chem Rev 2024; 124:768-859. [PMID: 38241488 DOI: 10.1021/acs.chemrev.3c00548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2024]
Abstract
Optoelectronic devices with unconventional form factors, such as flexible and stretchable light-emitting or photoresponsive devices, are core elements for the next-generation human-centric optoelectronics. For instance, these deformable devices can be utilized as closely fitted wearable sensors to acquire precise biosignals that are subsequently uploaded to the cloud for immediate examination and diagnosis, and also can be used for vision systems for human-interactive robotics. Their inception was propelled by breakthroughs in novel optoelectronic material technologies and device blueprinting methodologies, endowing flexibility and mechanical resilience to conventional rigid optoelectronic devices. This paper reviews the advancements in such soft optoelectronic device technologies, honing in on various materials, manufacturing techniques, and device design strategies. We will first highlight the general approaches for flexible and stretchable device fabrication, including the appropriate material selection for the substrate, electrodes, and insulation layers. We will then focus on the materials for flexible and stretchable light-emitting diodes, their device integration strategies, and representative application examples. Next, we will move on to the materials for flexible and stretchable photodetectors, highlighting the state-of-the-art materials and device fabrication methods, followed by their representative application examples. At the end, a brief summary will be given, and the potential challenges for further development of functional devices will be discussed as a conclusion.
Collapse
Affiliation(s)
- Sehui Chang
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
| | - Ja Hoon Koo
- Department of Semiconductor Systems Engineering, Sejong University, Seoul 05006, Republic of Korea
- Institute of Semiconductor and System IC, Sejong University, Seoul 05006, Republic of Korea
| | - Jisu Yoo
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Min Seok Kim
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
| | - Moon Kee Choi
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Graduate School of Semiconductor Materials and Devices Engineering, Center for Future Semiconductor Technology (FUST), UNIST, Ulsan 44919, Republic of Korea
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
| | - Dae-Hyeong Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University (SNU), Seoul 08826, Republic of Korea
- Department of Materials Science and Engineering, SNU, Seoul 08826, Republic of Korea
- Interdisciplinary Program for Bioengineering, SNU, Seoul 08826, Republic of Korea
| | - Young Min Song
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Artificial Intelligence (AI) Graduate School, GIST, Gwangju 61005, Republic of Korea
| |
Collapse
|
3
|
Muguet I, Maziz A, Mathieu F, Mazenq L, Larrieu G. Combining PEDOT:PSS Polymer Coating with Metallic 3D Nanowires Electrodes to Achieve High Electrochemical Performances for Neuronal Interfacing Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2302472. [PMID: 37385261 DOI: 10.1002/adma.202302472] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/18/2023] [Accepted: 05/26/2023] [Indexed: 07/01/2023]
Abstract
This study presents a novel approach to improve the performance of microelectrode arrays (MEAs) used for electrophysiological studies of neuronal networks. The integration of 3D nanowires (NWs) with MEAs increases the surface-to-volume ratio, which enables subcellular interactions and high-resolution neuronal signal recording. However, these devices suffer from high initial interface impedance and limited charge transfer capacity due to their small effective area. To overcome these limitations, the integration of conductive polymer coatings, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is investigated as a mean of improving the charge transfer capacity and biocompatibility of MEAs. The study combines platinum silicide-based metallic 3D nanowires electrodes with electrodeposited PEDOT:PSS coatings to deposit ultra-thin (<50 nm) layers of conductive polymer onto metallic electrodes with very high selectivity. The polymer-coated electrodes were fully characterized electrochemically and morphologically to establish a direct relationship between synthesis conditions, morphology, and conductive features. Results show that PEDOT-coated electrodes exhibit thickness-dependent improved stimulation and recording performances, offering new perspectives for neuronal interfacing with optimal cell engulfment to enable the study of neuronal activity with acute spatial and signal resolution at the sub-cellular level.
Collapse
Affiliation(s)
- Ines Muguet
- LAAS-CNRS, Université de Toulouse, CNRS, 7 avenue du colonel Roche, Toulouse, F-31400, France
| | - Ali Maziz
- LAAS-CNRS, Université de Toulouse, CNRS, 7 avenue du colonel Roche, Toulouse, F-31400, France
| | - Fabrice Mathieu
- LAAS-CNRS, Université de Toulouse, CNRS, 7 avenue du colonel Roche, Toulouse, F-31400, France
| | - Laurent Mazenq
- LAAS-CNRS, Université de Toulouse, CNRS, 7 avenue du colonel Roche, Toulouse, F-31400, France
| | - Guilhem Larrieu
- LAAS-CNRS, Université de Toulouse, CNRS, 7 avenue du colonel Roche, Toulouse, F-31400, France
| |
Collapse
|
4
|
Borda E, Medagoda DI, Airaghi Leccardi MJI, Zollinger EG, Ghezzi D. Conformable neural interface based on off-stoichiometry thiol-ene-epoxy thermosets. Biomaterials 2023; 293:121979. [PMID: 36586146 DOI: 10.1016/j.biomaterials.2022.121979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 11/29/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022]
Abstract
Off-stoichiometry thiol-ene-epoxy (OSTE+) thermosets show low permeability to gases and little absorption of dissolved molecules, allow direct low-temperature dry bonding without surface treatments, have a low Young's modulus, and can be manufactured via UV polymerisation. For these reasons, OSTE+ thermosets have recently gained attention for the rapid prototyping of microfluidic chips. Moreover, their compatibility with standard clean-room processes and outstanding mechanical properties make OSTE+ an excellent candidate as a novel material for neural implants. Here we exploit OSTE+ to manufacture a conformable multilayer micro-electrocorticography array with 16 platinum electrodes coated with platinum black. The mechanical properties allow conformability to curved surfaces such as the brain. The low permeability and strong adhesion between layers improve the stability of the device. Acute experiments in mice show the multimodal capacity of the array to record and stimulate the neural tissue by smoothly conforming to the mouse cortex. Devices are not cytotoxic, and immunohistochemistry stainings reveal only modest foreign body reaction after two and six weeks of chronic implantation. This work introduces OSTE+ as a promising material for implantable neural interfaces.
Collapse
Affiliation(s)
- Eleonora Borda
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Switzerland
| | - Danashi Imani Medagoda
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Switzerland
| | - Marta Jole Ildelfonsa Airaghi Leccardi
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Switzerland
| | - Elodie Geneviève Zollinger
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Switzerland
| | - Diego Ghezzi
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Switzerland.
| |
Collapse
|
5
|
Frenzel J, Kupferer A, Zink M, Mayr SG. Laminin Adsorption and Adhesion of Neurons and Glial Cells on Carbon Implanted Titania Nanotube Scaffolds for Neural Implant Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3858. [PMID: 36364633 PMCID: PMC9656521 DOI: 10.3390/nano12213858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/17/2022] [Accepted: 10/28/2022] [Indexed: 06/16/2023]
Abstract
Interfacing neurons persistently to conductive matter constitutes one of the key challenges when designing brain-machine interfaces such as neuroelectrodes or retinal implants. Novel materials approaches that prevent occurrence of loss of long-term adhesion, rejection reactions, and glial scarring are highly desirable. Ion doped titania nanotube scaffolds are a promising material to fulfill all these requirements while revealing sufficient electrical conductivity, and are scrutinized in the present study regarding their neuron-material interface. Adsorption of laminin, an essential extracellular matrix protein of the brain, is comprehensively analyzed. The implantation-dependent decline in laminin adsorption is revealed by employing surface characteristics such as nanotube diameter, ζ-potential, and surface free energy. Moreover, the viability of U87-MG glial cells and SH-SY5Y neurons after one and four days are investigated, as well as the material's cytotoxicity. The higher conductivity related to carbon implantation does not affect the viability of neurons, although it impedes glial cell proliferation. This gives rise to novel titania nanotube based implant materials with long-term stability, and could reduce undesirable glial scarring.
Collapse
Affiliation(s)
- Jan Frenzel
- Leibniz Institute of Surface Engineering (IOM), 04318 Leipzig, Germany
- Division of Surface Physics, Faculty of Physics and Earth Sciences, Leipzig University, 04103 Leipzig, Germany
- Research Group Biotechnology and Biomedicine, Faculty of Physics and Earth Sciences, Leipzig University, 04103 Leipzig, Germany
| | - Astrid Kupferer
- Leibniz Institute of Surface Engineering (IOM), 04318 Leipzig, Germany
- Division of Surface Physics, Faculty of Physics and Earth Sciences, Leipzig University, 04103 Leipzig, Germany
| | - Mareike Zink
- Research Group Biotechnology and Biomedicine, Faculty of Physics and Earth Sciences, Leipzig University, 04103 Leipzig, Germany
| | - Stefan G. Mayr
- Leibniz Institute of Surface Engineering (IOM), 04318 Leipzig, Germany
- Division of Surface Physics, Faculty of Physics and Earth Sciences, Leipzig University, 04103 Leipzig, Germany
| |
Collapse
|
6
|
Silveira C, Khushaba RN, Brunton E, Nazarpour K. Spatio-temporal feature extraction in sensory electroneurographic signals. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2022; 380:20210268. [PMID: 35658682 PMCID: PMC9289791 DOI: 10.1098/rsta.2021.0268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 11/08/2021] [Indexed: 06/15/2023]
Abstract
The recording and analysis of peripheral neural signal can provide insight for various prosthetic and bioelectronics medicine applications. However, there are few studies that investigate how informative features can be extracted from population activity electroneurographic (ENG) signals. In this study, five feature extraction frameworks were implemented on sensory ENG datasets and their classification performance was compared. The datasets were collected in acute rat experiments where multi-channel nerve cuffs recorded from the sciatic nerve in response to proprioceptive stimulation of the hindlimb. A novel feature extraction framework, which incorporates spatio-temporal focus and dynamic time warping, achieved classification accuracies above 90% while keeping a low computational cost. This framework outperformed the remaining frameworks tested in this study and has improved the discrimination accuracy of the sensory signals. Thus, this study has extended the tools available to extract features from sensory population activity ENG signals. This article is part of the theme issue 'Advanced neurotechnologies: translating innovation for health and well-being'.
Collapse
Affiliation(s)
- C. Silveira
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - R. N. Khushaba
- Australian Center for Field Robotics, The University of Sydney, New South Wales 2006, Australia
| | - E. Brunton
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria 3053, Australia
- Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - K. Nazarpour
- Edinburgh Neuroprosthetics Laboratory, School of Informatics, University of Edinburgh, Edinburgh EH8 9AB, UK
| |
Collapse
|
7
|
Akouissi O, Lacour SP, Micera S, DeSimone A. A finite element model of the mechanical interactions between peripheral nerves and intrafascicular implants. J Neural Eng 2022; 19. [PMID: 35861557 DOI: 10.1088/1741-2552/ac7d0e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 06/29/2022] [Indexed: 11/11/2022]
Abstract
Objective.Intrafascicular peripheral nerve implants are key components in the development of bidirectional neuroprostheses such as touch-enabled bionic limbs for amputees. However, the durability of such interfaces is hindered by the immune response following the implantation. Among the causes linked to such reaction, the mechanical mismatch between host nerve and implant is thought to play a decisive role, especially in chronic settings.Approach.Here we focus on modeling mechanical stresses induced on the peripheral nerve by the implant's micromotion using finite element analysis. Through multiple parametric sweeps, we analyze the role of the implant's material, geometry (aspect-ratio and shape), and surface coating, deriving a set of parameters for the design of better-integrated implants.Main results.Our results indicate that peripheral nerve implants should be designed and manufactured with smooth edges, using materials at most three orders of magnitude stiffer than the nerve, and with innovative geometries to redistribute micromotion-associated loads to less delicate parts of the nerve such as the epineurium.Significance.Overall, our model is a useful tool for the peripheral nerve implant designer that is mindful of the importance of implant mechanics for long term applications.
Collapse
Affiliation(s)
- Outman Akouissi
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Neuro-X Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Geneva, 1202, Switzerland.,Bertarelli Foundation Chair in Translational Neuroengineering, Translational Neural Engineering Laboratory, Neuro-X Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Geneva, 1202, Switzerland
| | - Stéphanie P Lacour
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Neuro-X Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Geneva, 1202, Switzerland
| | - Silvestro Micera
- Bertarelli Foundation Chair in Translational Neuroengineering, Translational Neural Engineering Laboratory, Neuro-X Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Geneva, 1202, Switzerland.,The Biorobotics Institute and Department of Excellence in Robotics & AI, Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Antonio DeSimone
- The Biorobotics Institute and Department of Excellence in Robotics & AI, Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Pisa, Italy.,SISSA-International School for Advanced Studies, 34136 Trieste, Italy
| |
Collapse
|
8
|
Doering M, Kieninger J, Urban GA, Weltin A. In situ stability monitoring of platinum thin-film electrodes for neural interfaces in the presence of proteins. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:1577-1580. [PMID: 36083919 DOI: 10.1109/embc48229.2022.9871177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The long-term stability of platinum electrodes is a key factor that determines the life-time of biomedical devices, such as implanted neural interfaces like brain stimulation or recording electrodes, cochlear implants, and biosensors. The downsizing of such devices relies on the usage of microfabricated thin-film electrodes. In order to determine and investigate the causal degradation processes for platinum electrodes, it is essential to use potential-controlled experiments, which allow selectable polarization of the electrode without exceeding the water stability window boundaries. Therefore, the surface processes and redox reactions occurring at the electrode are known at all times. In this study, we present the continuous in situ monitoring of platinum-based thin-film electrodes along their complete life cycle in neutral pH with and without the presence of proteins. The usage of chronoamperometry for electrode aging, monitoring of surface processes and the tracking of analyte redox processes, together with cyclic voltammetry to determine the complete amount of surface charge, allows a reliable quantification of fundamental degradation processes. We found that platinum dissolution is primarily driven by the formation and removal of Pt oxide. Despite the significantly lowered charge transfer, the presence of proteins did not prevent material loss or increase electrode lifetime. These results should be considered when interpreting results from current-controlled methods as typically used for neural interfaces. Clinical Relevance- All clinically relevant applications of microelectrodes, ranging from cell culture over diagnostics to in vivo use, involve the presence of proteins. Detailed and fundamental insight into electrode stability in the presence of proteins is therefore essential for successful clinical translation of neural interface technologies.
Collapse
|
9
|
Doering M, Kieninger J, Urban G, Weltin A. Electrochemical microelectrode degradation monitoring: in situ investigation of platinum corrosion at neutral pH. J Neural Eng 2022; 19. [PMID: 34983028 DOI: 10.1088/1741-2552/ac47da] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/04/2022] [Indexed: 11/11/2022]
Abstract
OBJECTIVE The stability of platinum and other noble metal electrodes is critical for neural implants, electrochemical sensors, and energy sources. Beyond the acidic or alkaline environment found in most electrochemical studies, the investigation of electrode corrosion in neutral pH and chloride containing electrolytes is essential, particularly regarding the long-term stability of neural interfaces, such as brain stimulation electrodes or cochlear implants. In addition, the increased use of microfabricated devices demands the investigation of thin-film electrode stability. APPROACH We developed a procedure of electrochemical methods for continuous tracking of electrode degradation in situ over the complete life cycle of platinum thin-film microelectrodes in a unique combination with simultaneous chemical sensing. We used chronoamperometry and cyclic voltammetry to measure electrode surface and analyte redox processes, together with accelerated electrochemical degradation. MAIN RESULTS We compared degradation between thin-film microelectrodes and bulk electrodes, neutral to acidic pH, different pulsing schemes, and the presence of the redox active species oxygen and hydrogen peroxide. Results were confirmed by mechanical profilometry and microscopy to determine material changes on a nanometer scale. We found that electrode degradation is mainly driven by repeated formation and removal of the platinum surface oxide, also within the electrochemical stability window of water. There was no considerable difference between thin-film micro- and macroscopic bulk electrodes or in the presence of reactive species, whereas acidic pH or extending the potential window led to increased degradation. SIGNIFICANCE Our results provide valuable fundamental information on platinum microelectrode degradation under conditions found in biomedical applications. For the first time, we deployed a unified method to report quantitative data on electrode degradation up to a defined endpoint. Our method is a widely applicable framework for comparative long-term studies of sensor and neural interface stability.
Collapse
Affiliation(s)
- Moritz Doering
- University of Freiburg, Georges-Köhler-Allee 103, Freiburg im Breisgau, Baden-Württemberg, 79110, GERMANY
| | - Jochen Kieninger
- University of Freiburg, Georges-Köhler-Allee 103, Freiburg im Breisgau, Baden-Württemberg, 79110, GERMANY
| | - Gerald Urban
- Department of Microsystems Engineering, Albert-Ludwigs-Universitat Freiburg, Georges-Köhler-Allee 103, Freiburg im Breisgau, 79110, GERMANY
| | - Andreas Weltin
- IMTEK - Department of Microsystems Engineering, University of Freiburg, Georges-Köhler-Allee 103, Freiburg im Breisgau, 79110, GERMANY
| |
Collapse
|
10
|
Liu J, Grayden DB, Keast JR, John SE. Computational Modeling of an Endovascular Peripheral Nerve Interface. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2021; 2021:5966-5969. [PMID: 34892477 DOI: 10.1109/embc46164.2021.9630085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Implantable neuromodulation devices that interface with the peripheral nervous system are a promising approach to restore functions lost to nerve damage. Existing nerve stimulation electrodes require direct contact with the target nerve and are associated with mechanical nerve damage and fibrous tissue encapsulation. Endovascularly delivered electrode arrays may provide a less invasive solution. Using a hybrid tissue conductor-neuron model and computational simulations, this study demonstrates the feasibility of delivering electrical stimulation of a peripheral nerve from a blood vessel in the vicinity of the target and predicts that the stimulation intensity required strongly depends on nerve-vessel distance and relative orientation, which are important factors to consider when screening candidate blood vessels for electrode implantation.
Collapse
|
11
|
Weltin A, Kieninger J. Electrochemical methods for neural interface electrodes. J Neural Eng 2021; 18. [PMID: 34547734 DOI: 10.1088/1741-2552/ac28d5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/21/2021] [Indexed: 11/11/2022]
Abstract
Objective. Neural interfaces often rely on charge transfer processes between electrodes and the tissue or electrolyte. Electrochemical processes are at the core of electrode function and, therefore, the key to neural interface stability, electrode performance characterization, and utilization of electrodes as chemical sensors. Electrochemical techniques offer a variety of options to investigate the charge transfer and electrocatalytic properties of electrodes.Approach. In this tutorial, we present various experiments to illustrate the power of electrochemical methods, serve as a reference and guideline, and stimulate deeper understanding of the subject.Main results.As a basis for the following experiments, we discuss the platinum cyclic voltammogram and focus on understanding surface processes and roughness determination. We highlight the importance of appropriate instrumentation using potentiostats and how strongly it can influence results. We then discuss a number of potential-controlled and current-controlled methods for electrode characterization, including chronocoulometry, chronoamperometry, (active) potentiometry, and chronopotentiometry. They illustrate charge transfer caused by both electrode surface processes and the presence of redox-active species, such as dissolved oxygen and hydrogen, or hydrogen peroxide. We also discuss the electrode potential with respect to a reference electrode under various conditions and how it affects its electrochemical properties like surface state, catalytic properties and capability to transfer charge.Significance.Electrochemical methods are still underutilized in neural engineering, and valuable information is therefore often not accessed. Many studies on electrode characterization would benefit from a more consistent and target-oriented electrochemical methodology and instrumentation. That ranges from the investigation of new materials and processes, over electrode performance assessment to the development of more long-term stable and biocompatible neural interfaces. Ultimately, standardization, consistency and comparability will play a key role in the translation of microtechnology into biomedical and clinical applications.
Collapse
Affiliation(s)
- Andreas Weltin
- Laboratory for Sensors, IMTEK-Department of Microsystems Engineering, University of Freiburg, Freiburg, Germany.,BrainLinks-BrainTools Center, University of Freiburg, Freiburg, Germany
| | - Jochen Kieninger
- Laboratory for Sensors, IMTEK-Department of Microsystems Engineering, University of Freiburg, Freiburg, Germany.,BrainLinks-BrainTools Center, University of Freiburg, Freiburg, Germany
| |
Collapse
|
12
|
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.
Collapse
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;
| |
Collapse
|
13
|
Lienemann S, Zötterman J, Farnebo S, Tybrandt K. Stretchable gold nanowire-based cuff electrodes for low-voltage peripheral nerve stimulation. J Neural Eng 2021; 18. [PMID: 33957608 DOI: 10.1088/1741-2552/abfebb] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 05/06/2021] [Indexed: 12/29/2022]
Abstract
Objective. Electrical stimulation of the peripheral nervous system (PNS) can treat various diseases and disorders, including the healing process after nerve injury. A major challenge when designing electrodes for PNS stimulation is the mechanical mismatch between the nerve and the device, which can lead to non-conformal contact, tissue damage and inefficient stimulation due to current leakage. Soft and stretchable cuff electrodes promise to tackle these challenges but often have limited performance and rely on unconventional materials. The aim of this study is to develop a high performance soft and stretchable cuff electrode based on inert materials for low-voltage nerve stimulation.Approach. We developed 50µm thick stretchable cuff electrodes based on silicone rubber, gold nanowire conductors and platinum coated nanowire electrodes. The electrode performance was characterized under strain cycling to assess the durability of the electrodes. The stimulation capability of the cuff electrodes was evaluated in anin vivosciatic nerve rat model by measuring the electromyography response to various stimulation pulses.Main results. The stretchable cuff electrodes showed excellent stability for 50% strain cycling and one million stimulation pulses. Saturated homogeneous stimulation of the sciatic nerve was achieved at only 200 mV due to the excellent conformability of the electrodes, the low conductor resistance (0.3 Ohm sq-1), and the low electrode impedance.Significance. The developed stretchable cuff electrode combines favourable mechanical properties and good electrode performance with inert and stable materials, making it ideal for low power supply applications within bioelectronic medicine.
Collapse
Affiliation(s)
- Samuel Lienemann
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, 601 74 Norrköping, Sweden
| | - Johan Zötterman
- Department of Hand Surgery, Plastic Surgery and Burns, Linköping University Hospital, Linköping, Sweden.,Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Simon Farnebo
- Department of Hand Surgery, Plastic Surgery and Burns, Linköping University Hospital, Linköping, Sweden.,Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Klas Tybrandt
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, 601 74 Norrköping, Sweden
| |
Collapse
|
14
|
Redolfi Riva E, Micera S. Progress and challenges of implantable neural interfaces based on nature-derived materials. Bioelectron Med 2021; 7:6. [PMID: 33902750 PMCID: PMC8077843 DOI: 10.1186/s42234-021-00067-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/31/2021] [Indexed: 12/31/2022] Open
Abstract
Neural interfaces are bioelectronic devices capable of stimulating a population of neurons or nerve fascicles and recording electrical signals in a specific area. Despite their success in restoring sensory-motor functions in people with disabilities, their long-term exploitation is still limited by poor biocompatibility, mechanical mismatch between the device and neural tissue and the risk of a chronic inflammatory response upon implantation.In this context, the use of nature-derived materials can help address these issues. Examples of these materials, such as extracellular matrix proteins, peptides, lipids and polysaccharides, have been employed for decades in biomedical science. Their excellent biocompatibility, biodegradability in the absence of toxic compound release, physiochemical properties that are similar to those of human tissues and reduced immunogenicity make them outstanding candidates to improve neural interface biocompatibility and long-term implantation safety. The objective of this review is to highlight progress and challenges concerning the impact of nature-derived materials on neural interface design. The use of these materials as biocompatible coatings and as building blocks of insulation materials for use in implantable neural interfaces is discussed. Moreover, future perspectives are presented to show the increasingly important uses of these materials for neural interface fabrication and their possible use for other applications in the framework of neural engineering.
Collapse
Affiliation(s)
- Eugenio Redolfi Riva
- The BioRobotics Institute and Department of Excellence in Robotics and AI, Scuola Superiore Sant'Anna, Pisa, Italy.
| | - Silvestro Micera
- The BioRobotics Institute and Department of Excellence in Robotics and AI, Scuola Superiore Sant'Anna, Pisa, Italy
- Bertarelli Foundation Chair in Translational Neuroengineering, Centre for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| |
Collapse
|
15
|
Sperry ZJ, Na K, Jun J, Madden LR, Socha A, Yoon E, Seymour JP, Bruns TM. High-density neural recordings from feline sacral dorsal root ganglia with thin-film array. J Neural Eng 2021; 18. [PMID: 33545709 DOI: 10.1088/1741-2552/abe398] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/05/2021] [Indexed: 12/26/2022]
Abstract
Objective. Dorsal root ganglia (DRG) are promising sites for recording sensory activity. Current technologies for DRG recording are stiff and typically do not have sufficient site density for high-fidelity neural data techniques.Approach. In acute experiments, we demonstrate single-unit neural recordings in sacral DRG of anesthetized felines using a 4.5µm thick, high-density flexible polyimide microelectrode array with 60 sites and 30-40µm site spacing. We delivered arrays into DRG with ultrananocrystalline diamond shuttles designed for high stiffness affording a smaller footprint. We recorded neural activity during sensory activation, including cutaneous brushing and bladder filling, as well as during electrical stimulation of the pudendal nerve and anal sphincter. We used specialized neural signal analysis software to sort densely packed neural signals.Main results. We successfully delivered arrays in five of six experiments and recorded single-unit sensory activity in four experiments. The median neural signal amplitude was 55μV peak-to-peak and the maximum unique units recorded at one array position was 260, with 157 driven by sensory or electrical stimulation. In one experiment, we used the neural analysis software to track eight sorted single units as the array was retracted ∼500μm.Significance. This study is the first demonstration of ultrathin, flexible, high-density electronics delivered into DRG, with capabilities for recording and tracking sensory information that are a significant improvement over conventional DRG interfaces.
Collapse
Affiliation(s)
- Zachariah J Sperry
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Kyounghwan Na
- Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, United States of America
| | - James Jun
- Flatiron Institute, Simons Foundation, New York City, NY, United States of America
| | - Lauren R Madden
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Alec Socha
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America.,Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, United States of America
| | - Eusik Yoon
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America.,Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, United States of America.,Center for Nanomedicine, Institute for Basic Science (IBS) and Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, Republic of Korea
| | - John P Seymour
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America.,Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, United States of America.,University of Texas Health Science Center, Department of Neurosurgery, Houston, TX, United States of America.,Department of Electrical and Computer Engineering, Rice University, Houston, TX, United States of America
| | - Tim M Bruns
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| |
Collapse
|
16
|
Abstract
Peripheral nerve interfaces (PNIs) record and/or modulate neural activity of nerves, which are responsible for conducting sensory-motor information to and from the central nervous system, and for regulating the activity of inner organs. PNIs are used both in neuroscience research and in therapeutical applications such as precise closed-loop control of neuroprosthetic limbs, treatment of neuropathic pain and restoration of vital functions (e.g. breathing and bladder management). Implantable interfaces represent an attractive solution to directly access peripheral nerves and provide enhanced selectivity both in recording and in stimulation, compared to their non-invasive counterparts. Nevertheless, the long-term functionality of implantable PNIs is limited by tissue damage, which occurs at the implant-tissue interface, and is thus highly dependent on material properties, biocompatibility and implant design. Current research focuses on the development of mechanically compliant PNIs, which adapt to the anatomy and dynamic movements of nerves in the body thereby limiting foreign body response. In this paper, we review recent progress in the development of flexible and implantable PNIs, highlighting promising solutions related to materials selection and their associated fabrication methods, and integrated functions. We report on the variety of available interface designs (intraneural, extraneural and regenerative) and different modulation techniques (electrical, optical, chemical) emphasizing the main challenges associated with integrating such systems on compliant substrates.
Collapse
Affiliation(s)
- Valentina Paggi
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland. Equally contributing authors
| | | | | | | |
Collapse
|
17
|
Abstract
When nerves are damaged by trauma or disease, they are still capable of firing off electrical command signals that originate from the brain. Furthermore, those damaged nerves have an innate ability to partially regenerate, so they can heal from trauma and even reinnervate new muscle targets. For an amputee who has his/her damaged nerves surgically reconstructed, the electrical signals that are generated by the reinnervated muscle tissue can be sensed and interpreted with bioelectronics to control assistive devices or robotic prostheses. No two amputees will have identical physiologies because there are many surgical options for reconstructing residual limbs, which may in turn impact how well someone can interface with a robotic prosthesis later on. In this review, we aim to investigate what the literature has to say about different pathways for peripheral nerve regeneration and how each pathway can impact the neuromuscular tissue’s final electrophysiology. This information is important because it can guide us in planning the development of future bioelectronic devices, such as prosthetic limbs or neurostimulators. Future devices will primarily have to interface with tissue that has undergone some natural regeneration process, and so we have explored and reported here what is known about the bioelectrical features of neuromuscular tissue regeneration.
Collapse
|
18
|
Llerena Zambrano B, Renz AF, Ruff T, Lienemann S, Tybrandt K, Vörös J, Lee J. Soft Electronics Based on Stretchable and Conductive Nanocomposites for Biomedical Applications. Adv Healthc Mater 2021; 10:e2001397. [PMID: 33205564 DOI: 10.1002/adhm.202001397] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/08/2020] [Indexed: 12/15/2022]
Abstract
Research on the field of implantable electronic devices that can be directly applied in the body with various functionalities is increasingly intensifying due to its great potential for various therapeutic applications. While conventional implantable electronics generally include rigid and hard conductive materials, their surrounding biological objects are soft and dynamic. The mechanical mismatch between implanted devices and biological environments induces damages in the body especially for long-term applications. Stretchable electronics with outstanding mechanical compliance with biological objects effectively improve such limitations of existing rigid implantable electronics. In this article, the recent progress of implantable soft electronics based on various conductive nanocomposites is systematically described. In particular, representative fabrication approaches of conductive and stretchable nanocomposites for implantable soft electronics and various in vivo applications of implantable soft electronics are focused on. To conclude, challenges and perspectives of current implantable soft electronics that should be considered for further advances are discussed.
Collapse
Affiliation(s)
- Byron Llerena Zambrano
- Laboratory of Biosensors and Bioelectronics ETH Zurich Gloriastrasse 35 Zurich 8092 Switzerland
| | - Aline F. Renz
- Laboratory of Biosensors and Bioelectronics ETH Zurich Gloriastrasse 35 Zurich 8092 Switzerland
| | - Tobias Ruff
- Laboratory of Biosensors and Bioelectronics ETH Zurich Gloriastrasse 35 Zurich 8092 Switzerland
| | - Samuel Lienemann
- Laboratory of Organic Electronics Department of Science and Technology Linköping University Norrköping 601 74 Sweden
| | - Klas Tybrandt
- Laboratory of Organic Electronics Department of Science and Technology Linköping University Norrköping 601 74 Sweden
| | - János Vörös
- Laboratory of Biosensors and Bioelectronics ETH Zurich Gloriastrasse 35 Zurich 8092 Switzerland
| | - Jaehong Lee
- Department of Robotics Engineering Daegu Gyeongbuk Institute of Science and Technology (DGIST) 333 Techno jungan‐dareo Daegu 42988 South Korea
| |
Collapse
|
19
|
Qi D, Zhang K, Tian G, Jiang B, Huang Y. Stretchable Electronics Based on PDMS Substrates. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2003155. [PMID: 32830370 DOI: 10.1002/adma.202003155] [Citation(s) in RCA: 129] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/05/2020] [Indexed: 05/27/2023]
Abstract
Stretchable electronics, which can retain their functions under stretching, have attracted great interest in recent decades. Elastic substrates, which bear the applied strain and regulate the strain distribution in circuits, are indispensable components in stretchable electronics. Moreover, the self-healing property of the substrate is a premise to endow stretchable electronics with the same characteristics, so the device may recover from failure resulting from large and frequent deformations. Therefore, the properties of the elastic substrate are crucial to the overall performance of stretchable devices. Poly(dimethylsiloxane) (PDMS) is widely used as the substrate material for stretchable electronics, not only because of its advantages, which include stable chemical properties, good thermal stability, transparency, and biological compatibility, but also because of its capability of attaining designer functionalities via surface modification and bulk property tailoring. Herein, the strategies for fabricating stretchable electronics on PDMS substrates are summarized, and the influence of the physical and chemical properties of PDMS, including surface chemical status, physical modulus, geometric structures, and self-healing properties, on the performance of stretchable electronics is discussed. Finally, the challenges and future opportunities of stretchable electronics based on PDMS substrates are considered.
Collapse
Affiliation(s)
- Dianpeng Qi
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Kuiyuan Zhang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Gongwei Tian
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Bo Jiang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| | - Yudong Huang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China
| |
Collapse
|
20
|
Rihani R, Tasnim N, Javed M, Usoro JO, D'Souza TM, Ware TH, Pancrazio JJ. Liquid Crystalline Polymers: Opportunities to Shape Neural Interfaces. Neuromodulation 2021; 25:1259-1267. [PMID: 33501705 DOI: 10.1111/ner.13364] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 12/21/2020] [Accepted: 01/05/2021] [Indexed: 01/11/2023]
Abstract
OBJECTIVES Polymers have emerged as constituent materials for the creation of microscale neural interfaces; however, limitations regarding water permeability, delamination, and material degradation impact polymeric device robustness. Liquid crystal polymers (LCPs) have molecular order like a solid but with the fluidity of a liquid, resulting in a unique material, with properties including low water permeability, chemical inertness, and mechanical toughness. The objective of this article is to review the state-of-the-art regarding the use of LCPs in neural interface applications and discuss challenges and opportunities where this class of materials can advance the field of neural interfaces. MATERIALS AND METHODS This review article focuses on studies that leverage LCP materials to interface with the nervous system in vivo. A comprehensive literature search was performed using PubMed, Web of Science (Clarivate Analytics), and Google Scholar. RESULTS There have been recent efforts to create neural interfaces that leverage the material advantages of LCPs. The literature offers examples of LCP as a basis for implantable medical devices and neural interfaces in the form of planar electrode arrays for retinal prosthetic, electrocorticography applications, and cuff-like structures for interfacing the peripheral nerve. In addition, there have been efforts to create penetrating intracortical devices capable of microstimulation and resolution of biopotentials. Recent work with a subclass of LCPs, namely liquid crystal elastomers, demonstrates that it is possible to create devices with features that deploy away from a central implantation site to interface with a volume of tissue while offering the possibility of minimizing tissue damage. CONCLUSION We envision the creation of novel microscale neural interfaces that leverage the physical properties of LCPs and have the capability of deploying within neural tissue for enhanced integration and performance.
Collapse
Affiliation(s)
- Rashed Rihani
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Nishat Tasnim
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Mahjabeen Javed
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA.,Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
| | - Joshua O Usoro
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Tania M D'Souza
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Taylor H Ware
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA.,Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA.,Department of Materials Science and Engineering, Texas A&M University, College Station, TX, USA
| | - Joseph J Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| |
Collapse
|
21
|
Maiolo L, Guarino V, Saracino E, Convertino A, Melucci M, Muccini M, Ambrosio L, Zamboni R, Benfenati V. Glial Interfaces: Advanced Materials and Devices to Uncover the Role of Astroglial Cells in Brain Function and Dysfunction. Adv Healthc Mater 2021; 10:e2001268. [PMID: 33103375 DOI: 10.1002/adhm.202001268] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 10/06/2020] [Indexed: 12/13/2022]
Abstract
Research over the past four decades has highlighted the importance of certain brain cells, called glial cells, and has moved the neurocentric vision of structure, function, and pathology of the nervous system toward a more holistic perspective. In this view, the demand for technologies that are able to target and both selectively monitor and control glial cells is emerging as a challenge across neuroscience, engineering, chemistry, and material science. Frequently neglected or marginally considered as a barrier to be overcome between neural implants and neuronal targets, glial cells, and in particular astrocytes, are increasingly considered as active players in determining the outcomes of device implantation. This review provides a concise overview not only of the previously established but also of the emerging physiological and pathological roles of astrocytes. It also critically discusses the most recent advances in biomaterial interfaces and devices that interact with glial cells and thus have enabled scientists to reach unprecedented insights into the role of astroglial cells in brain function and dysfunction. This work proposes glial interfaces and glial engineering as multidisciplinary fields that have the potential to enable significant advancement of knowledge surrounding cognitive function and acute and chronic neuropathologies.
Collapse
Affiliation(s)
- Luca Maiolo
- Consiglio Nazionale delle Ricerche Istituto per la Microelettronica e i Microsistemi Via del Fosso del Cavaliere n.100 Roma 00133 Italy
| | - Vincenzo Guarino
- Consiglio Nazionale delle Ricerche Istituto per i Polimeri Compositi e Biomateriali Viale J.F. Kennedy 54, Mostra d'Oltremare, Pad 20 Napoli 80125 Italy
| | - Emanuela Saracino
- Consiglio Nazionale delle Ricerche Istituto per la Sintesi Organica e la Fotoreattività via P. Gobetti 101 Bologna 40129 Italy
| | - Annalisa Convertino
- Consiglio Nazionale delle Ricerche Istituto per la Microelettronica e i Microsistemi Via del Fosso del Cavaliere n.100 Roma 00133 Italy
| | - Manuela Melucci
- Consiglio Nazionale delle Ricerche Istituto per la Sintesi Organica e la Fotoreattività via P. Gobetti 101 Bologna 40129 Italy
| | - Michele Muccini
- Consiglio Nazionale delle Ricerche Istituto per la Studio dei Materiali Nanostrutturati via P. Gobetti 101 Bologna 40129 Italy
| | - Luigi Ambrosio
- Consiglio Nazionale delle Ricerche Istituto per i Polimeri Compositi e Biomateriali Viale J.F. Kennedy 54, Mostra d'Oltremare, Pad 20 Napoli 80125 Italy
| | - Roberto Zamboni
- Consiglio Nazionale delle Ricerche Istituto per la Sintesi Organica e la Fotoreattività via P. Gobetti 101 Bologna 40129 Italy
| | - Valentina Benfenati
- Consiglio Nazionale delle Ricerche Istituto per la Sintesi Organica e la Fotoreattività via P. Gobetti 101 Bologna 40129 Italy
| |
Collapse
|
22
|
Renz AF, Lee J, Tybrandt K, Brzezinski M, Lorenzo DA, Cerra Cheraka M, Lee J, Helmchen F, Vörös J, Lewis CM. Opto-E-Dura: A Soft, Stretchable ECoG Array for Multimodal, Multiscale Neuroscience. Adv Healthc Mater 2020; 9:e2000814. [PMID: 32691992 DOI: 10.1002/adhm.202000814] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/30/2020] [Indexed: 11/07/2022]
Abstract
Soft, stretchable materials hold great promise for the fabrication of biomedical devices due to their capacity to integrate gracefully with and conform to biological tissues. Conformal devices are of particular interest in the development of brain interfaces where rigid structures can lead to tissue damage and loss of signal quality over the lifetime of the implant. Interfaces to study brain function and dysfunction increasingly require multimodal access in order to facilitate measurement of diverse physiological signals that span the disparate temporal and spatial scales of brain dynamics. Here the Opto-e-Dura, a soft, stretchable, 16-channel electrocorticography array that is optically transparent is presented. Its compatibility with diverse optical and electrical readouts is demonstrated enabling multimodal studies that bridge spatial and temporal scales. The device is chronically stable for weeks, compatible with wide-field and 2-photon calcium imaging and permits the repeated insertion of penetrating multielectrode arrays. As the variety of sensors and effectors realizable on soft, stretchable substrates expands, similar devices that provide large-scale, multimodal access to the brain will continue to improve fundamental understanding of brain function.
Collapse
Affiliation(s)
- Aline F. Renz
- Institute for Biomedical Engineering ETH Zurich Zurich 8092 Switzerland
| | - Jihyun Lee
- Institute for Biomedical Engineering ETH Zurich Zurich 8092 Switzerland
| | - Klas Tybrandt
- Institute for Biomedical Engineering ETH Zurich Zurich 8092 Switzerland
- Laboratory of Organic Electronics Department of Science and Technology Linköping University Norrköping 60174 Sweden
| | - Maciej Brzezinski
- Institute for Biomedical Engineering ETH Zurich Zurich 8092 Switzerland
| | - Dayra A. Lorenzo
- Laboratory of Neural Circuit Dynamics Brain Research Institute University of Zurich Zurich 8057 Switzerland
- Neuroscience Center Zurich University and ETH Zurich Zurich 8057 Switzerland
| | | | - Jaehong Lee
- Institute for Biomedical Engineering ETH Zurich Zurich 8092 Switzerland
| | - Fritjof Helmchen
- Laboratory of Neural Circuit Dynamics Brain Research Institute University of Zurich Zurich 8057 Switzerland
- Neuroscience Center Zurich University and ETH Zurich Zurich 8057 Switzerland
| | - Janos Vörös
- Institute for Biomedical Engineering ETH Zurich Zurich 8092 Switzerland
- Neuroscience Center Zurich University and ETH Zurich Zurich 8057 Switzerland
| | - Christopher M. Lewis
- Laboratory of Neural Circuit Dynamics Brain Research Institute University of Zurich Zurich 8057 Switzerland
| |
Collapse
|
23
|
Schiavone G, Fallegger F, Kang X, Barra B, Vachicouras N, Roussinova E, Furfaro I, Jiguet S, Seáñez I, Borgognon S, Rowald A, Li Q, Qin C, Bézard E, Bloch J, Courtine G, Capogrosso M, Lacour SP. Soft, Implantable Bioelectronic Interfaces for Translational Research. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1906512. [PMID: 32173913 DOI: 10.1002/adma.201906512] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/19/2019] [Indexed: 06/10/2023]
Abstract
The convergence of materials science, electronics, and biology, namely bioelectronic interfaces, leads novel and precise communication with biological tissue, particularly with the nervous system. However, the translation of lab-based innovation toward clinical use calls for further advances in materials, manufacturing and characterization paradigms, and design rules. Herein, a translational framework engineered to accelerate the deployment of microfabricated interfaces for translational research is proposed and applied to the soft neurotechnology called electronic dura mater, e-dura. Anatomy, implant function, and surgical procedure guide the system design. A high-yield, silicone-on-silicon wafer process is developed to ensure reproducible characteristics of the electrodes. A biomimetic multimodal platform that replicates surgical insertion in an anatomy-based model applies physiological movement, emulates therapeutic use of the electrodes, and enables advanced validation and rapid optimization in vitro of the implants. Functionality of scaled e-dura is confirmed in nonhuman primates, where epidural neuromodulation of the spinal cord activates selective groups of muscles in the upper limbs with unmet precision. Performance stability is controlled over 6 weeks in vivo. The synergistic steps of design, fabrication, and biomimetic in vitro validation and in vivo evaluation in translational animal models are of general applicability and answer needs in multiple bioelectronic designs and medical technologies.
Collapse
Affiliation(s)
- Giuseppe Schiavone
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Florian Fallegger
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Xiaoyang Kang
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Beatrice Barra
- Department of Neuroscience and Movement Science, University of Fribourg, Fribourg, 1700, Switzerland
| | - Nicolas Vachicouras
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Evgenia Roussinova
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Ivan Furfaro
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Sébastien Jiguet
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| | - Ismael Seáñez
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
| | - Simon Borgognon
- Department of Neuroscience and Movement Science, University of Fribourg, Fribourg, 1700, Switzerland
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
| | - Andreas Rowald
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
| | - Qin Li
- Institute of Lab Animal Sciences, China Academy of Medical Sciences, Beijing, 100021, China
- Motac Neuroscience Ltd, Manchester, SK10 4TF, UK
| | - Chuan Qin
- Institute of Lab Animal Sciences, China Academy of Medical Sciences, Beijing, 100021, China
| | - Erwan Bézard
- Institute of Lab Animal Sciences, China Academy of Medical Sciences, Beijing, 100021, China
- Motac Neuroscience Ltd, Manchester, SK10 4TF, UK
- Institut des Maladies Neurodégénératives, University of Bordeaux, Bordeaux, UMR 5293, France
- CNRS, Institut des Maladies Neurodégénératives, Bordeaux, UMR 5293, France
| | - Jocelyne Bloch
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
- Defitech Center for Interventional Neurotherapies (NeuroRestore), Department of Neurosurgery, University Hospital of Lausanne (CHUV), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Grégoire Courtine
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
- Defitech Center for Interventional Neurotherapies (NeuroRestore), Department of Neurosurgery, University Hospital of Lausanne (CHUV), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Marco Capogrosso
- Department of Neuroscience and Movement Science, University of Fribourg, Fribourg, 1700, Switzerland
| | - Stéphanie P Lacour
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronics Interface, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, 1202, Switzerland
| |
Collapse
|
24
|
Weltin A, Ganatra D, König K, Joseph K, Hofmann UG, Urban GA, Kieninger J. New life for old wires: electrochemical sensor method for neural implants. J Neural Eng 2019; 17:016007. [DOI: 10.1088/1741-2552/ab4c69] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
25
|
Affiliation(s)
- John F Zimmerman
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
| | - Bozhi Tian
- Department of Chemistry, the James Franck Institute, the Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA.
| |
Collapse
|