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Wang J, Liu H, Shi X, Qin S, Liu J, Lv Q, Liu J, Li Q, Wang Z, Wang L. Development and Application of an Advanced Biomedical Material-Silk Sericin. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2311593. [PMID: 38386199 DOI: 10.1002/adma.202311593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/18/2024] [Indexed: 02/23/2024]
Abstract
Sericin, a protein derived from silkworm cocoons, is considered a waste product derived from the silk industry for thousands of years due to a lack of understanding of its properties. However, in recent decades, a range of exciting properties of sericin are studied and uncovered, including cytocompatibility, low-immunogenicity, photo-luminescence, antioxidant properties, as well as cell-function regulating activities. These properties make sericin-based biomaterials promising candidates for biomedical applications. This review summarizes the properties and bioactivities of silk sericin and highlights the latest developments in sericin in tissue engineering and regenerative medicine. Furthermore, the extended application of sericin in developing flexible electronic devices and 3D bioprinting is also discussed. It is believed that sericin-based biomaterials have great potential of being developed into novel tissue engineering products and smart implantable devices for various medical applications toward improving clinical outcomes.
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Affiliation(s)
- Jian Wang
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Huan Liu
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xiaolei Shi
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Sumei Qin
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Jingwei Liu
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Qiying Lv
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Jia Liu
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Qilin's Li
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Zheng Wang
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Lin Wang
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
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2
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Wang Y, Xie Z, Huang H, Liang X. Pioneering healthcare with soft robotic devices: A review. SMART MEDICINE 2024; 3:e20230045. [PMID: 39188514 PMCID: PMC11235691 DOI: 10.1002/smmd.20230045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/25/2024] [Indexed: 08/28/2024]
Abstract
Recent advancements in soft robotics have been emerging as an exciting paradigm in engineering due to their inherent compliance, safe human interaction, and ease of adaptation with wearable electronics. Soft robotic devices have the potential to provide innovative solutions and expand the horizons of possibilities for biomedical applications by bringing robots closer to natural creatures. In this review, we survey several promising soft robot technologies, including flexible fluidic actuators, shape memory alloys, cable-driven mechanisms, magnetically driven mechanisms, and soft sensors. Selected applications of soft robotic devices as medical devices are discussed, such as surgical intervention, soft implants, rehabilitation and assistive devices, soft robotic exosuits, and prosthetics. We focus on how soft robotics can improve the effectiveness, safety and patient experience for each use case, and highlight current research and clinical challenges, such as biocompatibility, long-term stability, and durability. Finally, we discuss potential directions and approaches to address these challenges for soft robotic devices to move toward real clinical translations in the future.
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Affiliation(s)
- Yuzhe Wang
- Singapore Institute of Manufacturing TechnologyAgency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Zhen Xie
- Advanced Remanufacturing and Technology CentreAgency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Huishi Huang
- Advanced Remanufacturing and Technology CentreAgency for Science, Technology and Research (A*STAR)SingaporeSingapore
- Department of Mechanical EngineeringNational University of SingaporeSingaporeSingapore
| | - Xinquan Liang
- Singapore Institute of Manufacturing TechnologyAgency for Science, Technology and Research (A*STAR)SingaporeSingapore
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3
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Lin ZK, Lin JS, Chen ZH, Cheng HW, Huang WC, Chen SY. Electrogelated drug-embedded silk/gelatin/rGO degradable electrode for anti-inflammatory applications in brain-implant systems. J Mater Chem B 2024; 12:1361-1371. [PMID: 38234194 DOI: 10.1039/d3tb02715e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Implantable electrodes have raised great interest over the last years with the increasing incidence of neurodegenerative disorders. For brain implant devices, some key factors resulting in the formation of glial scars, such as mechanical mismatch and acute injury-induced inflammation, should be considered for material design. Therefore, in this study, a new biocompatible flexible electrode (e-SgG) with arbitrary shapes on a positive electrode was developed via electrogelation by applying a direct electrical voltage on a silk fibroin/gelatin/reduced graphene oxide composite hydrogel. The implantable flexible e-SgG-2 film with 1.23% rGO content showed high Young's modulus (11-150 MPa), which was sufficient for penetration under dried conditions but subsequently became a biomimetic brain tissue with low Young's modulus (50-3200 kPa) after insertion in the brain. At the same time, an anti-inflammatory drug (DEX) incorporated into the e-SgG-2 film can be electrically stimulated to exhibit two-stage release to overcome tissue inflammation during cyclic voltammetry via degradation by applying an AC field. The results of cell response to the SF/gelatin/rGO/DEX composite film showed that the released DEX could interrupt astrocyte growth to reduce the inflammatory response but showed non-toxicity toward neurons, which demonstrated a great potential for the application of the biocompatible and degradable e-SgG-D electrodes in the improvement of nerve tissue repair.
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Affiliation(s)
- Zhen-Kai Lin
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Jing-Syu Lin
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Zih-Huei Chen
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Hung-Wei Cheng
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Wei-Chen Huang
- Department of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - San-Yuan Chen
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
- Graduate Institute of Biomedical Science, China Medical University, Taichung, Taiwan
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
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Kim H, Rigo B, Wong G, Lee YJ, Yeo WH. Advances in Wireless, Batteryless, Implantable Electronics for Real-Time, Continuous Physiological Monitoring. NANO-MICRO LETTERS 2023; 16:52. [PMID: 38099970 PMCID: PMC10724104 DOI: 10.1007/s40820-023-01272-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 10/30/2023] [Indexed: 12/18/2023]
Abstract
This review summarizes recent progress in developing wireless, batteryless, fully implantable biomedical devices for real-time continuous physiological signal monitoring, focusing on advancing human health care. Design considerations, such as biological constraints, energy sourcing, and wireless communication, are discussed in achieving the desired performance of the devices and enhanced interface with human tissues. In addition, we review the recent achievements in materials used for developing implantable systems, emphasizing their importance in achieving multi-functionalities, biocompatibility, and hemocompatibility. The wireless, batteryless devices offer minimally invasive device insertion to the body, enabling portable health monitoring and advanced disease diagnosis. Lastly, we summarize the most recent practical applications of advanced implantable devices for human health care, highlighting their potential for immediate commercialization and clinical uses.
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Affiliation(s)
- Hyeonseok Kim
- IEN Center for Wearable Intelligent Systems and Healthcare, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Bruno Rigo
- IEN Center for Wearable Intelligent Systems and Healthcare, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Gabriella Wong
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Yoon Jae Lee
- IEN Center for Wearable Intelligent Systems and Healthcare, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Woon-Hong Yeo
- IEN Center for Wearable Intelligent Systems and Healthcare, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech and Emory University School of Medicine, Atlanta, GA, 30332, USA.
- Parker H. Petit Institute for Bioengineering and Biosciences, Institute for Materials, Institute for Robotics and Intelligent Machines, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
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5
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Krukiewicz K, Czerwińska-Główka D, Turczyn RM, Blacha-Grzechnik A, Vallejo-Giraldo C, Erfurt K, Chrobok A, Faure-Vincent J, Pouget S, Djurado D, Biggs MJ. Flexible, Transparent, and Cytocompatible Nanostructured Indium Tin Oxide Thin Films for Bio-optoelectronic Applications. ACS APPLIED MATERIALS & INTERFACES 2023; 15:45701-45712. [PMID: 37737728 PMCID: PMC10561142 DOI: 10.1021/acsami.3c10861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 09/08/2023] [Indexed: 09/23/2023]
Abstract
Electrical stimulation has been used successfully for several decades for the treatment of neurodegenerative disorders, including motor disorders, pain, and psychiatric disorders. These technologies typically rely on the modulation of neural activity through the focused delivery of electrical pulses. Recent research, however, has shown that electrically triggered neuromodulation can be further enhanced when coupled with optical stimulation, an approach that can benefit from the development of novel electrode materials that combine transparency with excellent electrochemical and biological performance. In this study, we describe an electrochemically modified, nanostructured indium tin oxide/poly(ethylene terephthalate) (ITO/PET) surface as a flexible, transparent, and cytocompatible electrode material. Electrochemical oxidation and reduction of ITO/PET electrodes in the presence of an ionic liquid based on d-glucopyranoside and bistriflamide units were performed, and the electrochemical behavior, conductivity, capacitance, charge transport processes, surface morphology, optical properties, and cytocompatibility were assessed in vitro. It has been shown that under selected conditions, electrochemically modified ITO/PET films remained transparent and highly conductive and were able to enhance neural cell survival and neurite outgrowth. Consequently, electrochemical modification of ITO/PET electrodes in the presence of an ionic liquid is introduced as an effective approach for tailoring the properties of ITO for advanced bio-optoelectronic applications.
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Affiliation(s)
- Katarzyna Krukiewicz
- Department
of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 44-100 Gliwice, Poland
- Centre
for Organic and Nanohybrid Electronics, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Dominika Czerwińska-Główka
- Department
of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Roman Maria Turczyn
- Department
of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 44-100 Gliwice, Poland
- Centre
for Organic and Nanohybrid Electronics, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Agata Blacha-Grzechnik
- Department
of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 44-100 Gliwice, Poland
- Centre
for Organic and Nanohybrid Electronics, Silesian University of Technology, 44-100 Gliwice, Poland
| | | | - Karol Erfurt
- Department
of Chemical Organic Technology and Petrochemistry, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Anna Chrobok
- Department
of Chemical Organic Technology and Petrochemistry, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Jérôme Faure-Vincent
- CEA/INAC/SPrAM,
Laboratoire d’Electronique Moléculaire Organique et
Hybride, 38000 Grenoble, France
| | - Stéphanie Pouget
- CEA/INAC/SPrAM,
Laboratoire d’Electronique Moléculaire Organique et
Hybride, 38000 Grenoble, France
| | - David Djurado
- CEA/INAC/SPrAM,
Laboratoire d’Electronique Moléculaire Organique et
Hybride, 38000 Grenoble, France
| | - Manus J.P. Biggs
- Centre
for Research in Medical Devices, University
of Galway, H91 TK33 Galway, Ireland
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6
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Maita F, Maiolo L, Lucarini I, Del Rio De Vicente JI, Sciortino A, Ledda M, Mussi V, Lisi A, Convertino A. Revealing Low Amplitude Signals of Neuroendocrine Cells through Disordered Silicon Nanowires-Based Microelectrode Array. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2301925. [PMID: 37357140 PMCID: PMC10460871 DOI: 10.1002/advs.202301925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 06/06/2023] [Indexed: 06/27/2023]
Abstract
Today, the key methodology to study in vitro or in vivo electrical activity in a population of electrogenic cells, under physiological or pathological conditions, is by using microelectrode array (MEA). While significant efforts have been devoted to develop nanostructured MEAs for improving the electrophysiological investigation in neurons and cardiomyocytes, data on the recording of the electrical activity from neuroendocrine cells with MEA technology are scarce owing to their weaker electrical signals. Disordered silicon nanowires (SiNWs) for developing a MEA that, combined with a customized acquisition board, successfully capture the electrical signals generated by the corticotrope AtT-20 cells as a function of the extracellular calcium (Ca2+ ) concentration are reported. The recorded signals show a shape that clearly resembles the action potential waveform by suggesting a natural membrane penetration of the SiNWs. Additionally, the generation of synchronous signals observed under high Ca2+ content indicates the occurrence of a collective behavior in the AtT-20 cell population. This study extends the usefulness of MEA technology to the investigation of the electrical communication in cells of the pituitary gland, crucial in controlling several essential human functions, and provides new perspectives in recording with MEA the electrical activity of excitable cells.
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Affiliation(s)
- Francesco Maita
- Institute for Microelectronics and MicrosystemsNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | - Luca Maiolo
- Institute for Microelectronics and MicrosystemsNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | - Ivano Lucarini
- Institute for Microelectronics and MicrosystemsNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | | | - Antonio Sciortino
- Institute for Microelectronics and MicrosystemsNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | - Mario Ledda
- Institute of Translational PharmacologyNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | - Valentina Mussi
- Institute for Microelectronics and MicrosystemsNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | - Antonella Lisi
- Institute of Translational PharmacologyNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
| | - Annalisa Convertino
- Institute for Microelectronics and MicrosystemsNational Research CouncilVia Fosso del Cavaliere 100Rome00133Italy
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7
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Hu Z, Niu Q, Hsiao BS, Yao X, Zhang Y. Bioactive polymer-enabled conformal neural interface and its application strategies. MATERIALS HORIZONS 2023; 10:808-828. [PMID: 36597872 DOI: 10.1039/d2mh01125e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Neural interface is a powerful tool to control the varying neuron activities in the brain, where the performance can directly affect the quality of recording neural signals and the reliability of in vivo connection between the brain and external equipment. Recent advances in bioelectronic innovation have provided promising pathways to fabricate flexible electrodes by integrating electrodes on bioactive polymer substrates. These bioactive polymer-based electrodes can enable the conformal contact with irregular tissue and result in low inflammation when compared to conventional rigid inorganic electrodes. In this review, we focus on the use of silk fibroin and cellulose biopolymers as well as certain synthetic polymers to offer the desired flexibility for constructing electrode substrates for a conformal neural interface. First, the development of a neural interface is reviewed, and the signal recording methods and tissue response features of the implanted electrodes are discussed in terms of biocompatibility and flexibility of corresponding neural interfaces. Following this, the material selection, structure design and integration of conformal neural interfaces accompanied by their effective applications are described. Finally, we offer our perspectives on the evolution of desired bioactive polymer-enabled neural interfaces, regarding the biocompatibility, electrical properties and mechanical softness.
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Affiliation(s)
- Zhanao Hu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, People's Republic of China.
| | - Qianqian Niu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, People's Republic of China.
| | - Benjamin S Hsiao
- Department of Chemistry, Stony Brook University, Stony Brook, New York, 11794-3400, USA
| | - Xiang Yao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, People's Republic of China.
| | - Yaopeng Zhang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, People's Republic of China.
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Terutsuki D, Yoroizuka H, Osawa SI, Ogihara Y, Abe H, Nakagawa A, Iwasaki M, Nishizawa M. Totally Organic Hydrogel-Based Self-Closing Cuff Electrode for Vagus Nerve Stimulation. Adv Healthc Mater 2022; 11:e2201627. [PMID: 36148587 DOI: 10.1002/adhm.202201627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/01/2022] [Indexed: 01/28/2023]
Abstract
An intrinsically soft organic electrode consisting of poly(3,4-ethylenedioxythiophene)-modified polyurethane (PEDOT-PU) is embedded into a bilayer film of polyvinyl alcohol (PVA) hydrogels for developing a self-closing cuff electrode for neuromodulation. The curled form of the PVA hydrogel is prepared by releasing internal stress in the bilayer structure. The inner diameter of the cuff electrode is set to less than 2 mm for immobilization to the vagus nerve (VN) of humans and pigs. The stability of the immobilization is examined, while the pressure applied to a nerve bundle is at a harmless level (≈200 Pa). Since the electrode is totally organic, MRI measurements can be conducted without image artifacts. The large electric capacitance of the PEDOT-PU (≈27 mF cm-2 ) ensures a safe stimulation of living tissues without Faradaic reactions. The practical performance of the cuff electrode for VN stimulation is demonstrated by observation of bradycardia induction in a pig.
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Affiliation(s)
- Daigo Terutsuki
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki Aoba, Aoba-ku, Sendai, 980-8579, Japan
| | - Hayato Yoroizuka
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki Aoba, Aoba-ku, Sendai, 980-8579, Japan
| | - Shin-Ichiro Osawa
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Yuka Ogihara
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki Aoba, Aoba-ku, Sendai, 980-8579, Japan
| | - Hiroya Abe
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki Aoba, Aoba-ku, Sendai, 980-8579, Japan
| | - Atsuhiro Nakagawa
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry (NCNP), 4-1-1 Ogawahigashi-cho, Kodaira-shi, Tokyo, 187-8551, Japan
| | - Matsuhiko Nishizawa
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki Aoba, Aoba-ku, Sendai, 980-8579, Japan
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9
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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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10
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Minute-sensitive real-time monitoring of neural cells through printed graphene microelectrodes. Biosens Bioelectron 2022; 210:114284. [DOI: 10.1016/j.bios.2022.114284] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/05/2022] [Accepted: 04/10/2022] [Indexed: 12/11/2022]
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11
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Li J, Ma Y, Huang D, Wang Z, Zhang Z, Ren Y, Hong M, Chen Y, Li T, Shi X, Cao L, Zhang J, Jiao B, Liu J, Sun H, Li Z. High-Performance Flexible Microneedle Array as a Low-Impedance Surface Biopotential Dry Electrode for Wearable Electrophysiological Recording and Polysomnography. NANO-MICRO LETTERS 2022; 14:132. [PMID: 35699782 PMCID: PMC9198145 DOI: 10.1007/s40820-022-00870-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 04/20/2022] [Indexed: 06/01/2023]
Abstract
Polyimide-based flexible microneedle array (PI-MNA) electrodes realize high electrical/mechanical performance and are compatible with wearable wireless recording systems. The normalized electrode-skin interface impedance (EII) of the PI-MNA electrodes reaches 0.98 kΩ cm2 at 1 kHz and 1.50 kΩ cm2 at 10 Hz, approximately 1/250 of clinical standard electrodes. This is the first report on the clinical study of microneedle electrodes. The PI-MNA electrodes are applied to clinical long-term continuous monitoring for polysomnography. Microneedle array (MNA) electrodes are an effective solution to achieve high-quality surface biopotential recording without the coordination of conductive gel and are thus very suitable for long-term wearable applications. Existing schemes are limited by flexibility, biosafety, and manufacturing costs, which create large barriers for wider applications. Here, we present a novel flexible MNA electrode that can simultaneously achieve flexibility of the substrate to fit a curved body surface, robustness of microneedles to penetrate the skin without fracture, and a simplified process to allow mass production. The compatibility with wearable wireless systems and the short preparation time of the electrodes significantly improves the comfort and convenience of electrophysiological recording. The normalized electrode-skin contact impedance reaches 0.98 kΩ cm2 at 1 kHz and 1.50 kΩ cm2 at 10 Hz, a record low value compared to previous reports and approximately 1/250 of the standard electrodes. The morphology, biosafety, and electrical/mechanical properties are fully characterized, and wearable recordings with a high signal-to-noise ratio and low motion artifacts are realized. The first reported clinical study of microneedle electrodes for surface electrophysiological monitoring was conducted in tens of healthy and sleep-disordered subjects with 44 nights of recording (over 8 h per night), providing substantial evidence that the electrodes can be leveraged to substitute for clinical standard electrodes.
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Affiliation(s)
- Junshi Li
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Yundong Ma
- Peking University Sixth Hospital, Peking University Institute of Mental Health, NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, People's Republic of China
| | - Dong Huang
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
- School of Electronics, Peking University, Beijing, 100871, People's Republic of China
- Hypnometry Microsystem, Beijing, 100871, People's Republic of China
| | - Zhongyan Wang
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Zhitong Zhang
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Yingjie Ren
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Mengyue Hong
- Peking University Sixth Hospital, Peking University Institute of Mental Health, NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, People's Republic of China
| | - Yufeng Chen
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Tingyu Li
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Xiaoyi Shi
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Lu Cao
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
- College of Engineering, Peking University, Beijing, 100871, People's Republic of China
| | - Jiayan Zhang
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Bingli Jiao
- School of Electronics, Peking University, Beijing, 100871, People's Republic of China
| | - Junhua Liu
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China
| | - Hongqiang Sun
- Peking University Sixth Hospital, Peking University Institute of Mental Health, NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, People's Republic of China.
| | - Zhihong Li
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Integrated Circuits, Peking University, Beijing, 100871, People's Republic of China.
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12
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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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13
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Niaraki A, McNamara MC, Montazami R, Hashemi NN. Graphene Microelectrodes for Real-Time Impedance Spectroscopy of Neural Cells. ACS APPLIED BIO MATERIALS 2022; 5:113-122. [PMID: 35014836 DOI: 10.1021/acsabm.1c00913] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Understanding the changes in the electrochemical properties of neural cells upon exposure to stress factors imparts vital information about the conditions prior to their death. This study presents a graphene-based biosensor for real-time monitoring of N27 rat dopaminergic neural cells which characterizes cell adhesion and cytotoxicity factors through impedance spectroscopy. The aim was to monitor the growth of the entire cell network via a nonmetallic flexible electrode array. Therefore, a water-based graphene solution was formulized as a conductive ink, 3D-printed into a flexible substrate through an electrohydrodynamic approach, resulting in electrodes with a conductivity of 6750 s/m. The presented high-throughput method enabled microscale monitoring of the entire cell network via the design of PDMS-based growth channels. The electrical resistance of the cell network was measured continuously along with their network density, constituting a mean density of 1890 cell/mm2 at full cell confluency. The results demonstrate the applicability of the impedance-based sensing of the cell network for rapid screening of the cytotoxic elements, and the real-time effect of UV exposure on dopaminergic neural cells was reported as an immediate application of the device.
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Affiliation(s)
- Amir Niaraki
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Marilyn C McNamara
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Reza Montazami
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Nicole N Hashemi
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011, United States.,Department of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
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14
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Thakur R, Aplin FP, Fridman GY. A Hydrogel-Based Microfluidic Nerve Cuff for Neuromodulation of Peripheral Nerves. MICROMACHINES 2021; 12:mi12121522. [PMID: 34945372 PMCID: PMC8706247 DOI: 10.3390/mi12121522] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/22/2021] [Accepted: 12/03/2021] [Indexed: 11/16/2022]
Abstract
Implantable neuromodulation devices typically have metal in contact with soft, ion-conducting nerves. These neural interfaces excite neurons using short-duration electrical pulses. While this approach has been extremely successful for multiple clinical applications, it is limited in delivering long-duration pulses or direct current (DC), even for acute term studies. When the charge injection capacity of electrodes is exceeded, irreversible electrochemical processes occur, and toxic byproducts are discharged directly onto the nerve, causing biological damage. Hydrogel coatings on electrodes improve the overall charge injection limit and provide a mechanically pliable interface. To further extend this idea, we developed a silicone-based nerve cuff lead with a hydrogel microfluidic conduit. It serves as a thin, soft and flexible interconnection and provides a greater spatial separation between metal electrodes and the target nerve. In an in vivo rat model, we used this cuff to stimulate and record from sciatic nerves, with performance comparable to that of metal electrodes. Further, we delivered DC through the lead in an acute manner to induce nerve block that is reversible. In contrast to most metallic cuff electrodes, which need microfabrication equipment, we built this cuff using a consumer-grade digital cutter and a simplified molding process. Overall, the device will be beneficial to neuromodulation researchers as a general-purpose nerve cuff electrode for peripheral neuromodulation experiments.
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Affiliation(s)
- Raviraj Thakur
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, Baltimore, MD 21205, USA; (R.T.); (F.P.A.)
| | - Felix P. Aplin
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, Baltimore, MD 21205, USA; (R.T.); (F.P.A.)
| | - Gene Y. Fridman
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, Baltimore, MD 21205, USA; (R.T.); (F.P.A.)
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
- Correspondence:
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15
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Zhang H, Liu Y, Zhou K, Wei W, Liu Y. Restoring Sensorimotor Function Through Neuromodulation After Spinal Cord Injury: Progress and Remaining Challenges. Front Neurosci 2021; 15:749465. [PMID: 34720867 PMCID: PMC8551759 DOI: 10.3389/fnins.2021.749465] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/13/2021] [Indexed: 12/27/2022] Open
Abstract
Spinal cord injury (SCI) is a major disability that results in motor and sensory impairment and extensive complications for the affected individuals which not only affect the quality of life of the patients but also result in a heavy burden for their families and the health care system. Although there are few clinically effective treatments for SCI, research over the past few decades has resulted in several novel treatment strategies which are related to neuromodulation. Neuromodulation-the use of neuromodulators, electrical stimulation or optogenetics to modulate neuronal activity-can substantially promote the recovery of sensorimotor function after SCI. Recent studies have shown that neuromodulation, in combination with other technologies, can allow paralyzed patients to carry out intentional, controlled movement, and promote sensory recovery. Although such treatments hold promise for completely overcoming SCI, the mechanisms by which neuromodulation has this effect have been difficult to determine. Here we review recent progress relative to electrical neuromodulation and optogenetics neuromodulation. We also examine potential mechanisms by which these methods may restore sensorimotor function. We then highlight the strengths of these approaches and remaining challenges with respect to its application.
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Affiliation(s)
- Hui Zhang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yaping Liu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Kai Zhou
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Wei Wei
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yaobo Liu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
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16
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Cho YH, Park YG, Kim S, Park JU. 3D Electrodes for Bioelectronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2005805. [PMID: 34013548 DOI: 10.1002/adma.202005805] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/04/2020] [Indexed: 05/08/2023]
Abstract
In recent studies related to bioelectronics, significant efforts have been made to form 3D electrodes to increase the effective surface area or to optimize the transfer of signals at tissue-electrode interfaces. Although bioelectronic devices with 2D and flat electrode structures have been used extensively for monitoring biological signals, these 2D planar electrodes have made it difficult to form biocompatible and uniform interfaces with nonplanar and soft biological systems (at the cellular or tissue levels). Especially, recent biomedical applications have been expanding rapidly toward 3D organoids and the deep tissues of living animals, and 3D bioelectrodes are getting significant attention because they can reach the deep regions of various 3D tissues. An overview of recent studies on 3D bioelectronic devices, such as the use of electrical stimulations and the recording of neural signals from biological subjects, is presented. Subsequently, the recent developments in materials and fabrication processing to 3D micro- and nanostructures are introduced, followed by broad applications of these 3D bioelectronic devices at various in vitro and in vivo conditions.
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Affiliation(s)
- Yo Han Cho
- Nano Science Technology Institute, Department of Materials Science and Engineering, Yonsei University, Seoul, 03722, Republic of Korea
- Center for Nanomedicine, Institute for Basic Science (IBS), Seoul, 03722, Republic of Korea
- Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, 03722, Republic of Korea
| | - Young-Geun Park
- Nano Science Technology Institute, Department of Materials Science and Engineering, Yonsei University, Seoul, 03722, Republic of Korea
- Center for Nanomedicine, Institute for Basic Science (IBS), Seoul, 03722, Republic of Korea
- Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, 03722, Republic of Korea
| | - Sumin Kim
- Nano Science Technology Institute, Department of Materials Science and Engineering, Yonsei University, Seoul, 03722, Republic of Korea
- Center for Nanomedicine, Institute for Basic Science (IBS), Seoul, 03722, Republic of Korea
- Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, 03722, Republic of Korea
| | - Jang-Ung Park
- Nano Science Technology Institute, Department of Materials Science and Engineering, Yonsei University, Seoul, 03722, Republic of Korea
- Center for Nanomedicine, Institute for Basic Science (IBS), Seoul, 03722, Republic of Korea
- Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, 03722, Republic of Korea
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17
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Schander A, Gancz JM, Tintelott M, Lang W. Towards Long-Term Stable Polyimide-Based Flexible Electrical Insulation for Chronically Implanted Neural Electrodes. MICROMACHINES 2021; 12:mi12111279. [PMID: 34832690 PMCID: PMC8619170 DOI: 10.3390/mi12111279] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/14/2021] [Accepted: 10/18/2021] [Indexed: 01/03/2023]
Abstract
For chronic applications of flexible neural implants, e.g., intracortical probes, the flexible substrate material has to encapsulate the electrical conductors with a long-term stability against the saline environment of the neural tissue. The biocompatible polymer polyimide is often used for this purpose. Due to its chemical inertness, the adhesion between two polyimide layers is, however, a challenge, which can lead to delamination and, finally, to short circuits. The state-of-the-art method to improve the adhesion strength is activating the polyimide surface using oxygen reactive ion etching (O2 RIE). However, the influence of the process variations (etching time, bias power) on the long-term stability is still unclear. Therefore, we establish a test method, where the aging of a gold interdigital structure embedded in two polyimide layers and immersed in saline solution is accelerated using an elevated temperature, mechanical stress and an electrical field. A continuous measurement of a leakage current is used to define the failure state. The results show that the variation of the O2 RIE plasma process has a significant effect on the long-term stability of the test samples. Comparing the two different plasma treatments 0.5 min at 25 W and 1 min at 50 W, the long-term stability could be increased from 20.9 ± 19.1 days to 44.9 ± 18.9 days. This corresponds to more than a doubled lifetime. An ideal solution for the delamination problem is still not available; however, the study shows that the fine-tuning of the fabrication processes can improve the long-term stability of chronically implanted neural electrodes.
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Affiliation(s)
- Andreas Schander
- Institute for Microsensors, -Actuators and -Systems (IMSAS), University of Bremen, 28359 Bremen, Germany; (J.M.G.); (M.T.); (W.L.)
- Correspondence: ; Tel.: +49-421-218-62590
| | - Julia M. Gancz
- Institute for Microsensors, -Actuators and -Systems (IMSAS), University of Bremen, 28359 Bremen, Germany; (J.M.G.); (M.T.); (W.L.)
| | - Marcel Tintelott
- Institute for Microsensors, -Actuators and -Systems (IMSAS), University of Bremen, 28359 Bremen, Germany; (J.M.G.); (M.T.); (W.L.)
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, 52074 Aachen, Germany
| | - Walter Lang
- Institute for Microsensors, -Actuators and -Systems (IMSAS), University of Bremen, 28359 Bremen, Germany; (J.M.G.); (M.T.); (W.L.)
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18
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Salahuddin U, Gao PX. Signal Generation, Acquisition, and Processing in Brain Machine Interfaces: A Unified Review. Front Neurosci 2021; 15:728178. [PMID: 34588951 PMCID: PMC8475516 DOI: 10.3389/fnins.2021.728178] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
Brain machine interfaces (BMIs), or brain computer interfaces (BCIs), are devices that act as a medium for communications between the brain and the computer. It is an emerging field with numerous applications in domains of prosthetic devices, robotics, communication technology, gaming, education, and security. It is noted in such a multidisciplinary field, many reviews have surveyed on various focused subfields of interest, such as neural signaling, microelectrode fabrication, and signal classification algorithms. A unified review is lacking to cover and link all the relevant areas in this field. Herein, this review intends to connect on the relevant areas that circumscribe BMIs to present a unified script that may help enhance our understanding of BMIs. Specifically, this article discusses signal generation within the cortex, signal acquisition using invasive, non-invasive, or hybrid techniques, and the signal processing domain. The latest development is surveyed in this field, particularly in the last decade, with discussions regarding the challenges and possible solutions to allow swift disruption of BMI products in the commercial market.
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Affiliation(s)
- Usman Salahuddin
- Institute of Materials Science, University of Connecticut, Storrs, CT, United States
| | - Pu-Xian Gao
- Institute of Materials Science, University of Connecticut, Storrs, CT, United States
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT, United States
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19
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Herbert R, Lim H, Park S, Kim J, Yeo W. Recent Advances in Printing Technologies of Nanomaterials for Implantable Wireless Systems in Health Monitoring and Diagnosis. Adv Healthc Mater 2021; 10:e2100158. [PMID: 34019731 DOI: 10.1002/adhm.202100158] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/03/2021] [Indexed: 12/17/2022]
Abstract
The development of wireless implantable sensors and integrated systems, enabled by advances in flexible and stretchable electronics technologies, is emerging to advance human health monitoring, diagnosis, and treatment. Progress in material and fabrication strategies allows for implantable electronics for unobtrusive monitoring via seamlessly interfacing with tissues and wirelessly communicating. Combining new nanomaterials and customizable printing processes offers unique possibilities for high-performance implantable electronics. Here, this report summarizes the recent progress and advances in nanomaterials and printing technologies to develop wireless implantable sensors and electronics. Advances in materials and printing processes are reviewed with a focus on challenges in implantable applications. Demonstrations of wireless implantable electronics and advantages based on these technologies are discussed. Lastly, existing challenges and future directions of nanomaterials and printing are described.
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Affiliation(s)
- Robert Herbert
- George W. Woodruff School of Mechanical Engineering Center for Human‐Centric Interfaces and Engineering Georgia Institute of Technology Atlanta GA 30332 USA
| | - Hyo‐Ryoung Lim
- George W. Woodruff School of Mechanical Engineering Center for Human‐Centric Interfaces and Engineering Georgia Institute of Technology Atlanta GA 30332 USA
| | - Sehyun Park
- School of Engineering and Computer Science Washington State University Vancouver WA 98686 USA
| | - Jong‐Hoon Kim
- School of Engineering and Computer Science Washington State University Vancouver WA 98686 USA
| | - Woon‐Hong Yeo
- George W. Woodruff School of Mechanical Engineering Center for Human‐Centric Interfaces and Engineering Georgia Institute of Technology Atlanta GA 30332 USA
- Wallace H. Coulter Department of Biomedical Engineering Parker H. Petit Institute for Bioengineering and Biosciences Neural Engineering Center Institute for Materials Institute for Robotics and Intelligent Machines Georgia Institute of Technology Atlanta GA 30332 USA
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20
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Lee WH, Cha GD, Kim DH. Flexible and biodegradable electronic implants for diagnosis and treatment of brain diseases. Curr Opin Biotechnol 2021; 72:13-21. [PMID: 34425329 DOI: 10.1016/j.copbio.2021.07.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 07/21/2021] [Accepted: 07/31/2021] [Indexed: 12/17/2022]
Abstract
In the diagnosis and treatment of brain diseases, implantable devices have immense potential for intracranial sensing of brain activity and application of controlled therapy for providing feedback to the sensing. Flexible materials are preferred for implantable devices, as they can minimise implanted device-brain tissue mechanical mismatch. Moreover, biodegradable implantable devices can reduce potential immunological side-effects. Biodegradability also helps avoid the burdensome secondary surgery for retrieving the implanted device. In this study, we reviewed recent advancements related to the use of flexible and biodegradable type of implantable devices for the diagnosis and treatment of brain diseases. Representative cases of intracranial sensing and feedback therapy are introduced, and then a brief discussion concludes the review.
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Affiliation(s)
- Wang Hee Lee
- 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, Seoul 08826, Republic of Korea
| | - Gi Doo Cha
- 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, 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, Seoul 08826, Republic of Korea; Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
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21
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Chiong JA, Tran H, Lin Y, Zheng Y, Bao Z. Integrating Emerging Polymer Chemistries for the Advancement of Recyclable, Biodegradable, and Biocompatible Electronics. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2101233. [PMID: 34014619 PMCID: PMC8292855 DOI: 10.1002/advs.202101233] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Indexed: 05/02/2023]
Abstract
Through advances in molecular design, understanding of processing parameters, and development of non-traditional device fabrication techniques, the field of wearable and implantable skin-inspired devices is rapidly growing interest in the consumer market. Like previous technological advances, economic growth and efficiency is anticipated, as these devices will enable an augmented level of interaction between humans and the environment. However, the parallel growing electronic waste that is yet to be addressed has already left an adverse impact on the environment and human health. Looking forward, it is imperative to develop both human- and environmentally-friendly electronics, which are contingent on emerging recyclable, biodegradable, and biocompatible polymer technologies. This review provides definitions for recyclable, biodegradable, and biocompatible polymers based on reported literature, an overview of the analytical techniques used to characterize mechanical and chemical property changes, and standard policies for real-life applications. Then, various strategies in designing the next-generation of polymers to be recyclable, biodegradable, or biocompatible with enhanced functionalities relative to traditional or commercial polymers are discussed. Finally, electronics that exhibit an element of recyclability, biodegradability, or biocompatibility with new molecular design are highlighted with the anticipation of integrating emerging polymer chemistries into future electronic devices.
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Affiliation(s)
- Jerika A. Chiong
- Department of ChemistryStanford UniversityStanfordCA94305‐5025USA
| | - Helen Tran
- Department of ChemistryUniversity of TorontoTorontoONM5S 3H6Canada
| | - Yangju Lin
- Department of Chemical EngineeringStanford UniversityStanfordCA94305‐5025USA
| | - Yu Zheng
- Department of ChemistryStanford UniversityStanfordCA94305‐5025USA
| | - Zhenan Bao
- Department of Chemical EngineeringStanford UniversityStanfordCA94305‐5025USA
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22
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Sunwoo SH, Ha KH, Lee S, Lu N, Kim DH. Wearable and Implantable Soft Bioelectronics: Device Designs and Material Strategies. Annu Rev Chem Biomol Eng 2021; 12:359-391. [PMID: 34097846 DOI: 10.1146/annurev-chembioeng-101420-024336] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
High-performance wearable and implantable devices capable of recording physiological signals and delivering appropriate therapeutics in real time are playing a pivotal role in revolutionizing personalized healthcare. However, the mechanical and biochemical mismatches between rigid, inorganic devices and soft, organic human tissues cause significant trouble, including skin irritation, tissue damage, compromised signal-to-noise ratios, and limited service time. As a result, profuse research efforts have been devoted to overcoming these issues by using flexible and stretchable device designs and soft materials. Here, we summarize recent representative research and technological advances for soft bioelectronics, including conformable and stretchable device designs, various types of soft electronic materials, and surface coating and treatment methods. We also highlight applications of these strategies to emerging soft wearable and implantable devices. We conclude with some current limitations and offer future prospects of this booming field.
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Affiliation(s)
- Sung-Hyuk Sunwoo
- 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, Seoul 08826, Republic of Korea
| | - Kyoung-Ho Ha
- Department of Mechanical Engineering, The University of Texas at Austin, Texas 78712, USA;
| | - Sangkyu Lee
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea;
| | - Nanshu Lu
- Department of Mechanical Engineering, The University of Texas at Austin, Texas 78712, USA; .,Center for Mechanics of Solids, Structures and Materials, Department of Aerospace Engineering and Engineering Mechanics, Department of Biomedical Engineering, and Texas Material Institute, The University of Texas at Austin, Texas 78712, USA
| | - 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, Seoul 08826, Republic of Korea.,Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea
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Precise and rapid solvent-assisted geometric protein self-patterning with submicron spatial resolution for scalable fabrication of microelectronic biosensors. Biosens Bioelectron 2021; 177:112968. [PMID: 33450615 DOI: 10.1016/j.bios.2021.112968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/08/2020] [Accepted: 01/01/2021] [Indexed: 11/22/2022]
Abstract
Precise and high-resolution coupling of functional proteins with micro-transducers is critical for the manufacture of miniaturized bioelectronic devices. Moreover, electrochemistry on microelectrodes has had a major impact on electrochemical analysis and sensor technologies, since the small size of microelectrode affects the radial diffusion flux of the analyte to deliver enhanced mass transport and electrode kinetics. However, a large technology gap has existed between the process technology associated with such microelectronics and the conventional bio-conjugation techniques that are generally used. Here, we report on a high-resolution and rapid geometric protein self-patterning (GPS) method using solvent-assisted protein-micelle adsorption printing to couple biomolecules onto microelectrodes with a minimum feature size of 5 μm and a printing time of about a minute. The GPS method is versatile for micropatterning various biomolecules including enzymes, antibodies and avidin-biotinylated proteins, delivering good geometric alignment and preserving biological functionality. We further demonstrated that enzyme-coupled microelectrodes for glucose detection exhibited good electrochemical performance which benefited from the GPS method to maximize effective signal transduction at the bio-interface. These microelectrode arrays maintained fast convergent analyte diffusion displaying typical steady-state I-V characteristics, fast response times, good linear sensitivity (0.103 nA mm-2 mM-1, R2 = 0.995) and an ultra-wide linear dynamic range (2-100 mM). Our findings provide a new technical solution for the precise and accurate coupling of biomolecules to a microelectronic array with important implications for the scaleup and manufacture of diagnostics, biofuel cells and bioelectronic devices that could not be realized economically by other existing techniques.
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Cai L, Gutruf P. Soft, Wireless and subdermally implantable recording and neuromodulation tools. J Neural Eng 2021; 18. [PMID: 33607646 DOI: 10.1088/1741-2552/abe805] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 02/19/2021] [Indexed: 12/14/2022]
Abstract
Progress in understanding neuronal interaction and circuit behavior of the central and peripheral nervous system strongly relies on the advancement of tools that record and stimulate with high fidelity and specificity. Currently, devices used in exploratory research predominantly utilize cables or tethers to provide pathways for power supply, data communication, stimulus delivery and recording, which constrains the scope and use of such devices. In particular, the tethered connection, mechanical mismatch to surrounding soft tissues and bones frustrate the interface leading to irritation and limitation of motion of the subject, which in the case of fundamental and preclinical studies, impacts naturalistic behaviors of animals and precludes the use in experiments involving social interaction and ethologically relevant three-dimensional environments, limiting the use of current tools to mostly rodents and exclude species such as birds and fish. This review explores the current state-of-the-art in wireless, subdermally implantable tools that quantitively expand capabilities in analysis and perturbation of the central and peripheral nervous system by removing tethers and externalized features of implantable neuromodulation and recording tools. Specifically, the review explores power harvesting strategies, wireless communication schemes, and soft materials and mechanics that enable the creation of such devices and discuss their capabilities in the context of freely-behaving subjects. Highlights of this class of devices includes wireless battery-free and fully implantable operation with capabilities in cell specific recording, multimodal neural stimulation and electrical, optogenetic and pharmacological neuromodulation capabilities. We conclude with discussion on translation of such technologies which promises routes towards broad dissemination.
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Affiliation(s)
- Le Cai
- Biomedical Engineering, University of Arizona, 1230 N Cherry Ave., Tucson, Arizona, 85719, UNITED STATES
| | - Philipp Gutruf
- Biomedical Engineering, University of Arizona, 1230 N Cherry Ave., Tucson, Arizona, 85719, UNITED STATES
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25
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Schiavone G, Kang X, Fallegger F, Gandar J, Courtine G, Lacour SP. Guidelines to Study and Develop Soft Electrode Systems for Neural Stimulation. Neuron 2020; 108:238-258. [PMID: 33120021 DOI: 10.1016/j.neuron.2020.10.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/23/2020] [Accepted: 10/08/2020] [Indexed: 12/13/2022]
Abstract
Electrical stimulation of nervous structures is a widely used experimental and clinical method to probe neural circuits, perform diagnostics, or treat neurological disorders. The recent introduction of soft materials to design electrodes that conform to and mimic neural tissue led to neural interfaces with improved functionality and biointegration. The shift from stiff to soft electrode materials requires adaptation of the models and characterization methods to understand and predict electrode performance. This guideline aims at providing (1) an overview of the most common techniques to test soft electrodes in vitro and in vivo; (2) a step-by-step design of a complete study protocol, from the lab bench to in vivo experiments; (3) a case study illustrating the characterization of soft spinal electrodes in rodents; and (4) examples of how interpreting characterization data can inform experimental decisions. Comprehensive characterization is paramount to advancing soft neurotechnology that meets the requisites for long-term functionality in vivo.
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Affiliation(s)
- Giuseppe Schiavone
- 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, 1202 Geneva, Switzerland
| | - Xiaoyang Kang
- 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, 1202 Geneva, Switzerland
| | - Florian Fallegger
- 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, 1202 Geneva, Switzerland
| | - Jérôme Gandar
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Grégoire Courtine
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland; Defitech Center for Interventional Neurotherapies (NeuroRestore), Department of Neurosurgery, University Hospital of Lausanne (CHUV) and University of Lausanne (UNIL), 1011 Lausanne, Switzerland
| | - Stéphanie P Lacour
- 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, 1202 Geneva, Switzerland.
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26
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Almasri RM, AlChamaa W, Tehrani-Bagha AR, Khraiche ML. Highly Flexible Single-Unit Resolution All Printed Neural Interface on a Bioresorbable Backbone. ACS APPLIED BIO MATERIALS 2020; 3:7040-7051. [DOI: 10.1021/acsabm.0c00895] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Reem M. Almasri
- Neural Engineering and Nanobiosensors Group, Biomedical Engineering Program, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Walid AlChamaa
- Neural Engineering and Nanobiosensors Group, Biomedical Engineering Program, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Ali Reza Tehrani-Bagha
- Department of Chemical Engineering and Advanced Energy, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Massoud L. Khraiche
- Neural Engineering and Nanobiosensors Group, Biomedical Engineering Program, Maroun Semaan Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
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27
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Apollo NV, Murphy B, Prezelski K, Driscoll N, Richardson AG, Lucas TH, Vitale F. Gels, jets, mosquitoes, and magnets: a review of implantation strategies for soft neural probes. J Neural Eng 2020; 17:041002. [PMID: 32759476 PMCID: PMC8152109 DOI: 10.1088/1741-2552/abacd7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Implantable neuroelectronic interfaces have enabled breakthrough advances in the clinical diagnosis and treatment of neurological disorders, as well as in fundamental studies of brain function, behavior, and disease. Intracranial electroencephalography (EEG) mapping with stereo-EEG (sEEG) depth electrodes is routinely adopted for precise epilepsy diagnostics and surgical treatment, while deep brain stimulation has become the standard of care for managing movement disorders. Intracortical microelectrode arrays for high-fidelity recordings of neural spiking activity have led to impressive demonstrations of the power of brain-machine interfaces for motor and sensory functional recovery. Yet, despite the rapid pace of technology development, the issue of establishing a safe, long-term, stable, and functional interface between neuroelectronic devices and the host brain tissue still remains largely unresolved. A body of work spanning at least the last 15 years suggests that safe, chronic integration between invasive electrodes and the brain requires a close match between the mechanical properties of man-made components and the neural tissue. In other words, the next generation of invasive electrodes should be soft and compliant, without sacrificing biological and chemical stability. Soft neuroelectronic interfaces, however, pose a new and significant surgical challenge: bending and buckling during implantation that can preclude accurate and safe device placement. In this topical review, we describe the next generation of soft electrodes and the surgical implantation methods for safe and precise insertion into brain structures. We provide an overview of the most recent innovations in the field of insertion strategies for flexible neural electrodes such as dissolvable or biodegradable carriers, microactuators, biologically-inspired support structures, and electromagnetic drives. In our analysis, we also highlight approaches developed in different fields, such as robotic surgery, which could be potentially adapted and translated to the insertion of flexible neural probes.
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Affiliation(s)
- Nicholas V Apollo
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, 19104, United States of America
| | - Brendan Murphy
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, 19104, United States of America
- These authors contributed equally
| | - Kayla Prezelski
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, 19104, United States of America
- These authors contributed equally
| | - Nicolette Driscoll
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, 19104, United States of America
| | - Andrew G Richardson
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
| | - Timothy H Lucas
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
| | - Flavia Vitale
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, 19104, United States of America
- These authors contributed equally
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States of America
- Department of Physical Medicine & Rehabilitation, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
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28
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Astoreca L, Cools P, Schaubroeck D, Asadian M, Aliakbarshirazi S, Declercq H, Op de Beeck M, Morent R, De Smet H, De Geyter N. Non-thermal plasma activation of BPDA-PPD polyimide for improved cell-material interaction. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122831] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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29
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Nishimura A, Suwabe R, Ogihara Y, Yoshida S, Abe H, Osawa SI, Nakagawa A, Tominaga T, Nishizawa M. Totally transparent hydrogel-based subdural electrode with patterned salt bridge. Biomed Microdevices 2020; 22:57. [PMID: 32827271 DOI: 10.1007/s10544-020-00517-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A totally transparent subdural electrode was developed by embedding a conductive poly (vinyl alcohol) (PVA)-filled microchannel made of poly(dimethylsiloxane) (PDMS) into an another PVA hydrogel substrate. Tight bonding between the PVA substrate and the PDMS microchannel (salt bridge) was achieved by mechanical interlocking utilizing the microprotrusions formed on the microchannel. This simple method of bonding without the use of any additives such as silane molecules or nanofibers is very suitable for constructing biomedical devices. The salt bridge electrode (total thickness, ca. 1.5 mm) was sufficiently soft, and showed superior shape conformability that makes it an excellent choice as a subdural electrode used on the brain surface. In vivo measurement proved that the salt bridge electrode makes close contact to the exposed porcine brain and can record brain wave signals of frequencies 1 ~ 15 Hz. In addition, the high transparency of the electrode provided a clear view of the brain surface that would assist the effective surgical operation and optogenetic research.
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Affiliation(s)
- Ayaka Nishimura
- Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, 6-6-04 Aoba-ku, Sendai, 980-8579, Japan
| | - Ryota Suwabe
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Yuka Ogihara
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Shotaro Yoshida
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Hiroya Abe
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan
| | - Shin-Ichiro Osawa
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Atsuhiro Nakagawa
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
- Division for the Establishment of Frontier Sciences of the Organization for Advanced Studies, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Matsuhiko Nishizawa
- Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, 6-6-04 Aoba-ku, Sendai, 980-8579, Japan.
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, 980-8579, Japan.
- Division for the Establishment of Frontier Sciences of the Organization for Advanced Studies, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.
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30
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Gao Y, Yu L, Yeo JC, Lim CT. Flexible Hybrid Sensors for Health Monitoring: Materials and Mechanisms to Render Wearability. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1902133. [PMID: 31339200 DOI: 10.1002/adma.201902133] [Citation(s) in RCA: 114] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/03/2019] [Indexed: 05/19/2023]
Abstract
Wearable electronics have revolutionized the way physiological parameters are sensed, detected, and monitored. In recent years, advances in flexible and stretchable hybrid electronics have created emergent properties that enhance the compliance of devices to our skin. With their unobtrusive attributes, skin conformable sensors enable applications toward real-time disease diagnosis and continuous healthcare monitoring. Herein, critical perspectives of flexible hybrid electronics toward the future of digital health monitoring are provided, emphasizing its role in physiological sensing. In particular, the strategies within the sensor composition to render flexibility and stretchability while maintaining excellent sensing performance are considered. Next, novel approaches to the functionalization of the sensor for physical or biochemical stimuli are extensively covered. Subsequently, wearable sensors measuring physical parameters such as strain, pressure, temperature, as well as biological changes in metabolites and electrolytes are reported. Finally, their implications toward early disease detection and monitoring are discussed, concluding with a future perspective into the challenges and opportunities in emerging wearable sensor designs for the next few years.
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Affiliation(s)
- Yuji Gao
- Department of Biomedical Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Longteng Yu
- Department of Biomedical Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Joo Chuan Yeo
- Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, 117599, Singapore
| | - Chwee Teck Lim
- Department of Biomedical Engineering, National University of Singapore, Singapore, 117583, Singapore
- Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, 117599, Singapore
- Mechanobiology Institute, National University of Singapore, Singapore, 117411, Singapore
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31
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Zhang C, Wen TH, Razak KA, Lin J, Xu C, Seo C, Villafana E, Jimenez H, Liu H. Magnesium-based biodegradable microelectrodes for neural recording. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 110:110614. [PMID: 32204062 DOI: 10.1016/j.msec.2019.110614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 10/23/2019] [Accepted: 12/26/2019] [Indexed: 12/21/2022]
Abstract
This article reports fabrication, characterization, degradation and electrical properties of biodegradable magnesium (Mg) microwires coated with two functional polymers, and the first in vivo evidence on the feasibility of Mg-based biodegradable microelectrodes for neural recording. Conductive poly(3,4‑ethylenedioxythiophene) (PEDOT) coating was first electrochemically deposited onto Mg microwire surface, and insulating biodegradable poly(glycerol sebacate) (PGS) was then spray-coated onto PEDOT surface to improve the overall properties of microelectrode. The assembled PGS/PEDOT-coated Mg microelectrodes showed high homogeneity in coating thickness, surface morphology and composition before and after in vivo recording. The charge storage capacity (CSC) of PGS/PEDOT-coated Mg microwire (1.72 mC/cm2) was nearly 5 times higher than the standard platinum (Pt) microwire widely used in implantable electrodes. The Mg-based microelectrode demonstrated excellent neural-recording capability and stability during in vivo multi-unit neural recordings in the auditory cortex of a mouse. Specifically, the Mg-based electrode showed clear and stable onset response, and excellent signal-to-noise ratio during spontaneous-activity recordings and three repeats of stimulus-evoked recordings at two different anatomical locations in the auditory cortex. During 10 days of immersion in artificial cerebrospinal fluid (aCSF) in vitro, PGS/PEDOT-coated Mg microelectrodes showed slower degradation and less change in impedance than PEDOT-coated Mg electrodes. The biodegradable PGS coating protected the PEDOT coating from delamination, and prolonged the mechanical integrity and electrical properties of Mg-based microelectrode. Mg-based novel microelectrodes should be further studied toward clinical translation because they can potentially eliminate the risks and costs associated with secondary surgeries for removal of failed or no longer needed electrodes.
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Affiliation(s)
- Chaoxing Zhang
- Materials Science and Engineering Program, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Teresa H Wen
- Neuroscience Graduate Program, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Khaleel A Razak
- Neuroscience Graduate Program, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Psychology Department, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Jiajia Lin
- Materials Science and Engineering Program, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Changlu Xu
- Materials Science and Engineering Program, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Catherine Seo
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Edgar Villafana
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Hector Jimenez
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - Huinan Liu
- Materials Science and Engineering Program, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Biomedical Sciences Program, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States; Stem Cell Center, University of California Riverside, 900 University Avenue, Riverside, CA 92521, United States.
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32
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Stamp MEM, Tong W, Ganesan K, Prawer S, Ibbotson MR, Garrett DJ. 3D Diamond Electrode Array for High-Acuity Stimulation in Neural Tissue. ACS APPLIED BIO MATERIALS 2020; 3:1544-1552. [DOI: 10.1021/acsabm.9b01165] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Melanie E. M. Stamp
- School of Physics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Wei Tong
- School of Physics, The University of Melbourne, Melbourne, Victoria 3010, Australia
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria 3053, Australia
- Department of Optometry and Vision Sciences, Melbourne School of Health Sciences, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Kumaravelu Ganesan
- School of Physics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Steven Prawer
- School of Physics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Michael R. Ibbotson
- National Vision Research Institute, Australian College of Optometry, Carlton, Victoria 3053, Australia
| | - David J. Garrett
- School of Physics, The University of Melbourne, Melbourne, Victoria 3010, Australia
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33
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Yang W, Gong Y, Li W. A Review: Electrode and Packaging Materials for Neurophysiology Recording Implants. Front Bioeng Biotechnol 2020; 8:622923. [PMID: 33585422 PMCID: PMC7873964 DOI: 10.3389/fbioe.2020.622923] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 12/10/2020] [Indexed: 01/28/2023] Open
Abstract
To date, a wide variety of neural tissue implants have been developed for neurophysiology recording from living tissues. An ideal neural implant should minimize the damage to the tissue and perform reliably and accurately for long periods of time. Therefore, the materials utilized to fabricate the neural recording implants become a critical factor. The materials of these devices could be classified into two broad categories: electrode materials as well as packaging and substrate materials. In this review, inorganic (metals and semiconductors), organic (conducting polymers), and carbon-based (graphene and carbon nanostructures) electrode materials are reviewed individually in terms of various neural recording devices that are reported in recent years. Properties of these materials, including electrical properties, mechanical properties, stability, biodegradability/bioresorbability, biocompatibility, and optical properties, and their critical importance to neural recording quality and device capabilities, are discussed. For the packaging and substrate materials, different material properties are desired for the chronic implantation of devices in the complex environment of the body, such as biocompatibility and moisture and gas hermeticity. This review summarizes common solid and soft packaging materials used in a variety of neural interface electrode designs, as well as their packaging performances. Besides, several biopolymers typically applied over the electrode package to reinforce the mechanical rigidity of devices during insertion, or to reduce the immune response and inflammation at the device-tissue interfaces are highlighted. Finally, a benchmark analysis of the discussed materials and an outlook of the future research trends are concluded.
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Affiliation(s)
- Weiyang Yang
- Microtechnology Lab, Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI, United States
| | - Yan Gong
- Microtechnology Lab, Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI, United States
| | - Wen Li
- Microtechnology Lab, Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI, United States
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34
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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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Thakur R, Jin A, Nair A, Fridman G. Nerve cuff electrode pressure estimation via electrical impedance measurement. J Neural Eng 2019; 16:064003. [PMID: 31557736 DOI: 10.1088/1741-2552/ab486f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Implantable neuromodulation devices that have cuff electrodes are known to exert mechanical pressure on the target nerves. The amount of pressure exerted by cuff enclosures is one of the key determinants of physiological safety of these devices since excess pressures can cause neural damage. Because direct measurements of pressure on a nerve are challenging, the current cuff design approaches rely heavily on theoretical models or numerical computations for pressure predictions. An experimental approach to test these devices for pressure can complement existing theoretical models and can also serve as a quality control step to screen cuff electrode designs before implantation. APPROACH We hypothesize that the pressure exerted on a nerve by a cuff can be estimated by measuring the resulting changes to the nerve's electrical impedance. MAIN RESULTS We investigated ten 1 cm-long explanted rat sciatic nerves: five that were used within an hour after surgery, and five after 50 h of storage in physiological saline. For each experiment we applied variable pressure on the nerve ex vivo and measured the resulting changes in its impedance. We found a strong correlation between the external pressure on the nerve and its impedance and generated a pressure-impedance calibration curve. At the upper limit of physiologically safe pressure, the nerve impedance increased by ~2 kΩ, whereas, a rise of ~3 kΩ corresponded to pressure value that onsets irreversible nerve damage. SIGNIFICANCE As a proof-of-concept, we used this protocol to generate a pressure-impedance calibration curve for a monkey tibial nerve and estimated pressure exerted by a commercial silicone cuff electrode on the explanted nerve. This single-point measurement was in an agreement with an independent estimate of the pressure measured using a mechanical pull test within 3 mmHg.
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Affiliation(s)
- Raviraj Thakur
- Department of Otolaryngology Head and Neck Surgery, Johns Hopkins University, Baltimore, Maryland, United States of America
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36
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Vachicouras N, Tarabichi O, Kanumuri VV, Tringides CM, Macron J, Fallegger F, Thenaisie Y, Epprecht L, McInturff S, Qureshi AA, Paggi V, Kuklinski MW, Brown MC, Lee DJ, Lacour SP. Microstructured thin-film electrode technology enables proof of concept of scalable, soft auditory brainstem implants. Sci Transl Med 2019; 11:eaax9487. [PMID: 31619546 DOI: 10.1126/scitranslmed.aax9487] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 09/26/2019] [Indexed: 12/21/2022]
Abstract
Auditory brainstem implants (ABIs) provide sound awareness to deaf individuals who are not candidates for the cochlear implant. The ABI electrode array rests on the surface of the cochlear nucleus (CN) in the brainstem and delivers multichannel electrical stimulation. The complex anatomy and physiology of the CN, together with poor spatial selectivity of electrical stimulation and inherent stiffness of contemporary multichannel arrays, leads to only modest auditory outcomes among ABI users. Here, we hypothesized that a soft ABI could enhance biomechanical compatibility with the curved CN surface. We developed implantable ABIs that are compatible with surgical handling, conform to the curvature of the CN after placement, and deliver efficient electrical stimulation. The soft ABI array design relies on precise microstructuring of plastic-metal-plastic multilayers to enable mechanical compliance, patterning, and electrical function. We fabricated soft ABIs to the scale of mouse and human CN and validated them in vitro. Experiments in mice demonstrated that these implants reliably evoked auditory neural activity over 1 month in vivo. Evaluation in human cadaveric models confirmed compatibility after insertion using an endoscopic-assisted craniotomy surgery, ease of array positioning, and robustness and reliability of the soft electrodes. This neurotechnology offers an opportunity to treat deafness in patients who are not candidates for the cochlear implant, and the design and manufacturing principles are broadly applicable to implantable soft bioelectronics throughout the central and peripheral nervous system.
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Affiliation(s)
- Nicolas Vachicouras
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Osama Tarabichi
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Vivek V Kanumuri
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Christina M Tringides
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Jennifer Macron
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Florian Fallegger
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Yohann Thenaisie
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Lorenz Epprecht
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen McInturff
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Ahad A Qureshi
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Valentina Paggi
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
| | - Martin W Kuklinski
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - M Christian Brown
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel J Lee
- Eaton-Peabody Laboratories and Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA.
| | - Stéphanie P Lacour
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland.
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Sheiko SS, Dobrynin AV. Architectural Code for Rubber Elasticity: From Supersoft to Superfirm Materials. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01127] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Sergei S. Sheiko
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Andrey V. Dobrynin
- Department of Polymer Science, University of Akron, Akron, Ohio 44325-3909, United States
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38
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Yu L, Feng Y, S/O M Tamil Selven D, Yao L, Soon RH, Yeo JC, Lim CT. Dual-Core Capacitive Microfiber Sensor for Smart Textile Applications. ACS APPLIED MATERIALS & INTERFACES 2019; 11:33347-33355. [PMID: 31424908 DOI: 10.1021/acsami.9b10937] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Wearable sensors for smart textile applications have garnered tremendous interest in recent years and can have enormous potential for human machine interfaces and digital health monitoring. Here, we report a soft capacitive microfiber sensor that can be woven seamlessly into textiles for strain measurement. Comprising a dual-lumen elastomeric microtube and liquid metallic alloy, the microfiber sensor enables continual strain perception even after being completely severed. In addition, our microfiber sensor is highly stretchable and flexible and exhibits tunable sensitivity, excellent linearity, a fast response, and negligible hysteresis. More importantly, the microfiber sensor is minimally affected by train rate and compression during strain sensing. Even under drastic environmental changes, the microfiber sensor presents good electrical stability. By integrating the microfiber sensor imperceptibly with textiles, we devise smart textile wearables to interpret hand gestures, detect limb motion, and monitor respiration rate. We believe that this sensor presents enormous potential in unobtrusive continuous health monitoring.
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Affiliation(s)
- Longteng Yu
- Department of Biomedical Engineering , National University of Singapore , Singapore 117583 , Singapore
| | - Yuqin Feng
- Department of Biomedical Engineering , National University of Singapore , Singapore 117583 , Singapore
- NUS Graduate School for Integrative Sciences and Engineering , National University of Singapore , Singapore 119077 , Singapore
| | - Dinesh S/O M Tamil Selven
- Department of Biomedical Engineering , National University of Singapore , Singapore 117583 , Singapore
| | - Liangsong Yao
- Department of Materials Science and Engineering , National University of Singapore , Singapore 117575 , Singapore
| | - Ren Hao Soon
- Department of Biomedical Engineering , National University of Singapore , Singapore 117583 , Singapore
| | - Joo Chuan Yeo
- Institute for Health Innovation and Technology , National University of Singapore , Singapore 117599 , Singapore
| | - Chwee Teck Lim
- Department of Biomedical Engineering , National University of Singapore , Singapore 117583 , Singapore
- NUS Graduate School for Integrative Sciences and Engineering , National University of Singapore , Singapore 119077 , Singapore
- Institute for Health Innovation and Technology , National University of Singapore , Singapore 117599 , Singapore
- Mechanobiology Institute , National University of Singapore , Singapore 117411 , Singapore
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Liu Z, Wang H, Huang P, Huang J, Zhang Y, Wang Y, Yu M, Chen S, Qi D, Wang T, Jiang Y, Chen G, Hu G, Li W, Yu J, Luo Y, Loh XJ, Liedberg B, Li G, Chen X. Highly Stable and Stretchable Conductive Films through Thermal-Radiation-Assisted Metal Encapsulation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1901360. [PMID: 31282042 DOI: 10.1002/adma.201901360] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/21/2019] [Indexed: 06/09/2023]
Abstract
Stretchable conductors are the basic units of advanced flexible electronic devices, such as skin-like sensors, stretchable batteries and soft actuators. Current fabrication strategies are mainly focused on the stretchability of the conductor with less emphasis on the huge mismatch of the conductive material and polymeric substrate, which results in stability issues during long-term use. Thermal-radiation-assisted metal encapsulation is reported to construct an interlocking layer between polydimethylsiloxane (PDMS) and gold by employing a semipolymerized PDMS substrate to encapsulate the gold clusters/atoms during thermal deposition. The stability of the stretchable conductor is significantly enhanced based on the interlocking effect of metal and polymer, with high interfacial adhesion (>2 MPa) and cyclic stability (>10 000 cycles). Also, the conductor exhibits superior properties such as high stretchability (>130%) and large active surface area (>5:1 effective surface area/geometrical area). It is noted that this method can be easily used to fabricate such a stretchable conductor in a wafer-scale format through a one-step process. As a proof of concept, both long-term implantation in an animal model to monitor intramuscular electric signals and on human skin for detection of biosignals are demonstrated. This design approach brings about a new perspective on the exploration of stretchable conductors for biomedical applications.
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Affiliation(s)
- Zhiyuan Liu
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Hui Wang
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
- Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Pingao Huang
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
- Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Jianping Huang
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
| | - Yu Zhang
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
| | - Yuanyuan Wang
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
| | - Mei Yu
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
| | - Shixiong Chen
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
| | - Dianpeng Qi
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Ting Wang
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Ying Jiang
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Geng Chen
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Guoyu Hu
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Wenlong Li
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Jiancan Yu
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Yifei Luo
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Xian Jun Loh
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Bo Liedberg
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Guanglin Li
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, 518055, China
| | - Xiaodong Chen
- Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
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40
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Classification of naturally evoked compound action potentials in peripheral nerve spatiotemporal recordings. Sci Rep 2019; 9:11145. [PMID: 31366940 PMCID: PMC6668407 DOI: 10.1038/s41598-019-47450-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 07/10/2019] [Indexed: 01/21/2023] Open
Abstract
Peripheral neural signals have the potential to provide the necessary motor, sensory or autonomic information for robust control in many neuroprosthetic and neuromodulation applications. However, developing methods to recover information encoded in these signals is a significant challenge. We introduce the idea of using spatiotemporal signatures extracted from multi-contact nerve cuff electrode recordings to classify naturally evoked compound action potentials (CAP). 9 Long-Evan rats were implanted with a 56-channel nerve cuff on the sciatic nerve. Afferent activity was selectively evoked in the different fascicles of the sciatic nerve (tibial, peroneal, sural) using mechano-sensory stimuli. Spatiotemporal signatures of recorded CAPs were used to train three different classifiers. Performance was measured based on the classification accuracy, F1-score, and the ability to reconstruct original firing rates of neural pathways. The mean classification accuracies, for a 3-class problem, for the best performing classifier was 0.686 ± 0.126 and corresponding mean F1-score was 0.605 ± 0.212. The mean Pearson correlation coefficients between the original firing rates and estimated firing rates found for the best classifier was 0.728 ± 0.276. The proposed method demonstrates the possibility of classifying individual naturally evoked CAPs in peripheral neural signals recorded from extraneural electrodes, allowing for more precise control signals in neuroprosthetic applications.
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41
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Control of neural probe shank flexibility by fluidic pressure in embedded microchannel using PDMS/PI hybrid substrate. PLoS One 2019; 14:e0220258. [PMID: 31339963 PMCID: PMC6655783 DOI: 10.1371/journal.pone.0220258] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/11/2019] [Indexed: 11/19/2022] Open
Abstract
Implantable neural probes are widely used to record and stimulate neural activities. These probes should be stiff enough for insertion. However, it should also be flexible to minimize tissue damage after insertion. Therefore, having dynamic control of the neural probe shank flexibility will be useful. For the first time, we have successfully fabricated flexible neural probes with embedded microfluidic channels for dynamic control of neural probe stiffness by controlling fluidic pressure in the channels. The present hybrid neural probes consisted of polydimethylsiloxane (PDMS) and polyimide (PI) layers could provide the required stiffness for insertion and flexibility during operation. The PDMS channels were fabricated by reversal imprint using a silicon mold and bonded to a PI layer to form the embedded channels in the neural probe. The probe shape was patterned using an oxygen plasma generated by an inductively coupled plasma etching system. The critical buckling force of PDMS/PI neural probes could be tuned from 0.25-1.25 mN depending on the applied fluidic pressure in the microchannels and these probes were successfully inserted into a 0.6% agarose gel that mimicked the stiffness of the brain tissue. Polymer-based neural probes are typically more flexible than conventional metal wire-based probes, and they could potentially provide less tissue damage after implantation.
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42
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Decataldo F, Cramer T, Martelli D, Gualandi I, Korim WS, Yao ST, Tessarolo M, Murgia M, Scavetta E, Amici R, Fraboni B. Stretchable Low Impedance Electrodes for Bioelectronic Recording from Small Peripheral Nerves. Sci Rep 2019; 9:10598. [PMID: 31332219 PMCID: PMC6646361 DOI: 10.1038/s41598-019-46967-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 07/03/2019] [Indexed: 12/24/2022] Open
Abstract
Monitoring of bioelectric signals in peripheral sympathetic nerves of small animal models is crucial to gain understanding of how the autonomic nervous system controls specific body functions related to disease states. Advances in minimally-invasive electrodes for such recordings in chronic conditions rely on electrode materials that show low-impedance ionic/electronic interfaces and elastic mechanical properties compliant with the soft and fragile nerve strands. Here we report a highly stretchable low-impedance electrode realized by microcracked gold films as metallic conductors covered with stretchable conducting polymer composite to facilitate ion-to-electron exchange. The conducting polymer composite based on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) obtains its adhesive, low-impedance properties by controlling thickness, plasticizer content and deposition conditions. Atomic Force Microscopy measurements under strain show that the optimized conducting polymer coating is compliant with the micro-crack mechanics of the underlying Au-layer, necessary to absorb the tensile deformation when the electrodes are stretched. We demonstrate functionality of the stretchable electrodes by performing high quality recordings of renal sympathetic nerve activity under chronic conditions in rats.
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Affiliation(s)
| | - Tobias Cramer
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy.
| | - Davide Martelli
- Department of Biomedical and Neuromotor Sciences - Physiology, University of Bologna, Bologna, Italy
| | - Isacco Gualandi
- Department of Industrial Chemistry, University of Bologna, Bologna, Italy
| | - Willian S Korim
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia
| | - Song T Yao
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia
| | - Marta Tessarolo
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Mauro Murgia
- Instituto per lo Studio dei Materiali Nanostrutturati (ISMN), Centro Nazionale delle Ricerche (CNR), Via Gobetti 101, 40129, Bologna, Italy
| | - Erika Scavetta
- Department of Industrial Chemistry, University of Bologna, Bologna, Italy
| | - Roberto Amici
- Department of Biomedical and Neuromotor Sciences - Physiology, University of Bologna, Bologna, Italy
| | - Beatrice Fraboni
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
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Boehler C, Oberueber F, Asplund M. Tuning drug delivery from conducting polymer films for accurately controlled release of charged molecules. J Control Release 2019; 304:173-180. [PMID: 31096016 DOI: 10.1016/j.jconrel.2019.05.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 05/12/2019] [Indexed: 02/01/2023]
Abstract
Spatio-temporally controlled drug release based on conducting polymer films offers a powerful technology to improve the tissue integration for implantable neuroprobes. We here explore the release efficiency of such systems in order to improve the understanding of the release mechanism and allow for optimized implementation of this technology into future drug release applications. By exposing drug loaded PEDOT coatings of different thicknesses to a multitude of release signals, along with optimizing the steps during the polymer synthesis, we could identify a highly reproducible electrostatically controlled drug release next to a slow diffusion driven release component. The release efficiency was moreover observed to be higher for a cyclic voltammetry signal in comparison to release driven by a constant potential. Biphasic current pulses, as used during neural stimulation, did not allow for long enough diffusion times to yield efficient active drug expulsion from the polymer films. A quantitative analysis could confirm an overall linear dependency between drug release and film thickness. The amount of drug released in response to the trigger signals was however not linearly correlated with the amount of charge applied. By combining these findings we could develop a model which accurately describes the drug release mechanism from a PEDOT film. The proposed model thereby points the way for how actively controlled, and diffusion related, release can be tuned for obtaining delivery dynamics tailored to specific applications.
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Affiliation(s)
- Christian Boehler
- BrainLinks-BrainTools Center, University of Freiburg, Germany; Department of Microsystems Engineering (IMTEK), University of Freiburg, Germany.
| | - Felix Oberueber
- BrainLinks-BrainTools Center, University of Freiburg, Germany; Department of Microsystems Engineering (IMTEK), University of Freiburg, Germany
| | - Maria Asplund
- BrainLinks-BrainTools Center, University of Freiburg, Germany; Department of Microsystems Engineering (IMTEK), University of Freiburg, Germany
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Wen X, Wang B, Huang S, Liu TL, Lee MS, Chung PS, Chow YT, Huang IW, Monbouquette HG, Maidment NT, Chiou PY. Flexible, multifunctional neural probe with liquid metal enabled, ultra-large tunable stiffness for deep-brain chemical sensing and agent delivery. Biosens Bioelectron 2019; 131:37-45. [PMID: 30818131 PMCID: PMC6602555 DOI: 10.1016/j.bios.2019.01.060] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/21/2019] [Accepted: 01/24/2019] [Indexed: 10/27/2022]
Abstract
Flexible neural probes have been pursued previously to minimize the mechanical mismatch between soft neural tissues and implants and thereby improve long-term performance. However, difficulties with insertion of such probes deep into the brain severely restricts their utility. We describe a solution to this problem using gallium (Ga) in probe construction, taking advantage of the solid-to-liquid phase change of the metal at body temperature and probe shape deformation to provide temperature-dependent control of stiffness over 5 orders of magnitude. Probes in the stiff state were successfully inserted 2 cm-deep into agarose gel "brain phantoms" and into rat brains under cooled conditions where, upon Ga melting, they became ultra soft, flexible, and stretchable in all directions. The current 30 μm-thick probes incorporated multilayer, deformable microfluidic channels for chemical agent delivery, electrical interconnects through Ga wires, and high-performance electrochemical glutamate sensing. These PDMS-based microprobes of ultra-large tunable stiffness (ULTS) should serve as an attractive platform for multifunctional chronic neural implants.
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Affiliation(s)
- Ximiao Wen
- Department of Mechanical and Aerospace Engineering, University of California at Los Angeles, Los Angeles, CA, USA
| | - Bo Wang
- Department of Psychiatry & Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, CA, USA
| | - Shan Huang
- Department of Biological Chemistry, University of California at Los Angeles, CA, USA
| | - Tingyi Leo Liu
- Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, MA, USA
| | - Meng-Shiue Lee
- Department of Mechanical Engineering, National Chiao Tung University, Hsinchu, Taiwan
| | - Pei-Shan Chung
- Department of Bioengineering, University of California at Los Angeles, CA, USA
| | - Yu Ting Chow
- Department of Mechanical and Aerospace Engineering, University of California at Los Angeles, Los Angeles, CA, USA
| | - I-Wen Huang
- Department of Chemical and Biomolecular Engineering, University of California at Los Angeles, CA, USA
| | - Harold G Monbouquette
- Department of Chemical and Biomolecular Engineering, University of California at Los Angeles, CA, USA
| | - Nigel T Maidment
- Department of Psychiatry & Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, CA, USA.
| | - Pei-Yu Chiou
- Department of Mechanical and Aerospace Engineering, University of California at Los Angeles, Los Angeles, CA, USA; Department of Bioengineering, University of California at Los Angeles, CA, USA.
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Krukiewicz K, Janas D, Vallejo-Giraldo C, Biggs MJ. Self-supporting carbon nanotube films as flexible neural interfaces. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.10.157] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Ecker M, Joshi-Imre A, Modi R, Frewin CL, Garcia-Sandoval A, Maeng J, Gutierrez-Heredia G, Pancrazio JJ, Voit WE. From softening polymers to multimaterial based bioelectronic devices. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/2399-7532/aaed58] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Renz AF, Reichmuth AM, Stauffer F, Thompson-Steckel G, Vörös J. A guide towards long-term functional electrodes interfacing neuronal tissue. J Neural Eng 2018; 15:061001. [DOI: 10.1088/1741-2552/aae0c2] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Abstract
OBJECTIVE In many applications, multielectrode arrays employed as neural implants require a high density and a high number of electrodes to precisely record and stimulate the activity of the nervous system while preserving the overall size of the array. APPROACH Here we present a multilayer and three-dimensional (3D) electrode array, together with its manufacturing method, enabling a higher electrode density and a more efficient signal transduction with the biological tissue. MAIN RESULTS The 3D structure of the electrode array allows for a multilayer placement of the interconnects within a flexible substrate, it narrows the probe size per the same number of electrodes, and it maintains the electrode contacts at the same level within the tissue. In addition, it augments the electrode surface area, leading to a lower electrochemical impedance and a higher charge storage capacity. To characterize the recordings capabilities of the multilayer 3D electrodes, we measured visually evoked cortical potentials in mice and analysed the evolution of the peak prominences and latencies according to different light intensities and recording depths within the brain. The resulting signal-to-noise ratio is improved compared to flat electrodes. Finally, the 3D electrodes have been imaged inside a clarified mouse brain using a light-sheet microscope to visualize their integrity within the tissue. SIGNIFICANCE The multilayer 3D electrodes have proved to be a valid technology to ensure tissue proximity and higher recording/stimulating efficiencies while enabling higher electrode density and reducing the probe size.
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Affiliation(s)
- Marta Jole Ildelfonsa Airaghi Leccardi
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Caldwell R, Mandal H, Sharma R, Solzbacher F, Tathireddy P, Rieth L. Analysis of Al 2O 3-parylene C bilayer coatings and impact of microelectrode topography on long term stability of implantable neural arrays. J Neural Eng 2018; 14:046011. [PMID: 28351998 DOI: 10.1088/1741-2552/aa69d3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Performance of many dielectric coatings for neural electrodes degrades over time, contributing to loss of neural signals and evoked percepts. Studies using planar test substrates have found that a novel bilayer coating of atomic-layer deposited (ALD) Al2O3 and parylene C is a promising candidate for neural electrode applications, exhibiting superior stability to parylene C alone. However, initial results from bilayer encapsulation testing on non-planar devices have been less positive. Our aim was to evaluate ALD Al2O3-parylene C coatings using novel test paradigms, to rigorously evaluate dielectric coatings for neural electrode applications by incorporating neural electrode topography into test structure design. APPROACH Five test devices incorporated three distinct topographical features common to neural electrodes, derived from the utah electrode array (UEA). Devices with bilayer (52 nm Al2O3 + 6 µm parylene C) were evaluated against parylene C controls (N ⩾ 6 per device type). Devices were aged in phosphate buffered saline at 67 °C for up to 311 d, and monitored through: (1) leakage current to evaluate encapsulation lifetimes (>1 nA during 5VDC bias indicated failure), and (2) wideband (1-105 Hz) impedance. MAIN RESULTS Mean-times-to-failure (MTTFs) ranged from 12 to 506 d for bilayer-coated devices, versus 10 to >2310 d for controls. Statistical testing (log-rank test, α = 0.05) of failure rates gave mixed results but favored the control condition. After failure, impedance loss for bilayer devices continued for months and manifested across the entire spectrum, whereas the effect was self-limiting after several days, and restricted to frequencies <100 Hz for controls. These results correlated well with observations of UEAs encapsulated with bilayer and control films. SIGNIFICANCE We observed encapsulation failure modes and behaviors comparable to neural electrode performance which were undetected in studies with planar test devices. We found the impact of parylene C defects to be exacerbated by ALD Al2O3, and conclude that inferior bilayer performance arises from degradation of ALD Al2O3 when directly exposed to saline. This is an important consideration, given that neural electrodes with bilayer coatings are expected to have ALD Al2O3 exposed at dielectric boundaries that delineate electrode sites. Process improvements and use of different inorganic coatings to decrease dissolution in physiological fluids may improve performance. Testing frameworks which take neural electrode complexities into account will be well suited to reliably evaluate such encapsulation schemes.
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Affiliation(s)
- Ryan Caldwell
- Department of Bioengineering, University of Utah, Salt Lake City, UT, United States of America
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Bettinger CJ. Recent advances in materials and flexible electronics for peripheral nerve interfaces. Bioelectron Med 2018; 4:6. [PMID: 32232082 PMCID: PMC7098226 DOI: 10.1186/s42234-018-0007-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 05/03/2018] [Indexed: 11/10/2022] Open
Abstract
Peripheral nerve interfaces are a central technology in advancing bioelectronic medicines because these medical devices can record and modulate the activity of nerves that innervate visceral organs. Peripheral nerve interfaces that use electrical signals for recording or stimulation have advanced our collective understanding of the peripheral nervous system. Furthermore, devices such as cuff electrodes and multielectrode arrays of various form factors have been implanted in the peripheral nervous system of humans in several therapeutic contexts. Substantive advances have been made using devices composed of off-the-shelf commodity materials. However, there is also a demand for improved device performance including extended chronic reliability, enhanced biocompatibility, and increased bandwidth for recording and stimulation. These aspirational goals manifest as much needed improvements in device performance including: increasing mechanical compliance (reducing Young's modulus and increasing extensibility); improving the barrier properties of encapsulation materials; reducing impedance and increasing the charge injection capacity of electrode materials; and increasing the spatial resolution of multielectrode arrays. These proposed improvements require new materials and novel microfabrication strategies. This mini-review highlights selected recent advances in flexible electronics for peripheral nerve interfaces. The foci of this mini-review include novel materials for flexible and stretchable substrates, non-conventional microfabrication techniques, strategies for improved device packaging, and materials to improve signal transduction across the tissue-electrode interface. Taken together, this article highlights challenges and opportunities in materials science and processing to improve the performance of peripheral nerve interfaces and advance bioelectronic medicine.
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Affiliation(s)
- Christopher J. Bettinger
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 USA
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 USA
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