1
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Foremny K, Konerding WS, Behrens A, Baumhoff P, Froriep UP, Kral A, Doll T. Carbon-Nanotube-Coated Surface Electrodes for Cortical Recordings In Vivo. NANOMATERIALS 2021; 11:nano11041029. [PMID: 33920671 PMCID: PMC8073035 DOI: 10.3390/nano11041029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/12/2021] [Accepted: 04/15/2021] [Indexed: 11/16/2022]
Abstract
Current developments of electrodes for neural recordings address the need of biomedical research and applications for high spatial acuity in electrophysiological recordings. One approach is the usage of novel materials to overcome electrochemical constraints of state-of-the-art metal contacts. Promising materials are carbon nanotubes (CNTs), as they are well suited for neural interfacing. The CNTs increase the effective contact surface area to decrease high impedances while keeping minimal contact diameters. However, to prevent toxic dissolving of CNTs, an appropriate surface coating is required. In this study, we tested flexible surface electrocorticographic (ECoG) electrodes, coated with a CNT-silicone rubber composite. First, we describe the outcome of surface etching, which exposes the contact nanostructure while anchoring the CNTs. Subsequently, the ECoG electrodes were used for acute in vivo recordings of auditory evoked potentials from the guinea pig auditory cortex. Both the impedances and the signal-to-noise ratios of coated contacts were similar to uncoated gold contacts. This novel approach for a safe application of CNTs, embedded in a surface etched silicone rubber, showed promising results but did not lead to improvements during acute recordings.
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Affiliation(s)
- Katharina Foremny
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
- Correspondence:
| | - Wiebke S. Konerding
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Ailke Behrens
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Peter Baumhoff
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Ulrich P. Froriep
- Division of Translational Biomedical Engineering, Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, 30625 Hannover, Germany;
| | - Andrej Kral
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
| | - Theodor Doll
- Institute of AudioNeuroTechnology and Department of Experimental Otology, ENT Clinic, Hannover Medical School, 30625 Hannover, Germany; (W.S.K.); (A.B.); (P.B.); (A.K.); (T.D.)
- Division of Translational Biomedical Engineering, Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, 30625 Hannover, Germany;
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2
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Chen N, Luo B, Patil AC, Wang J, Gammad GGL, Yi Z, Liu X, Yen SC, Ramakrishna S, Thakor NV. Nanotunnels within Poly(3,4-ethylenedioxythiophene)-Carbon Nanotube Composite for Highly Sensitive Neural Interfacing. ACS NANO 2020; 14:8059-8073. [PMID: 32579337 DOI: 10.1021/acsnano.0c00672] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Neural electrodes are developed for direct communication with neural tissues for theranostics. Although various strategies have been employed to improve performance, creating an intimate electrode-tissue interface with high electrical fidelity remains a great challenge. Here, we report the rational design of a tunnel-like electrode coating comprising poly(3,4-ethylenedioxythiophene) (PEDOT) and carbon nanotubes (CNTs) for highly sensitive neural recording. The coated electrode shows a 50-fold reduction in electrochemical impedance at the biologically relevant frequency of 1 kHz, compared to the bare gold electrode. The incorporation of CNT significantly reinforces the nanotunnel structure and improves coating adhesion by ∼1.5 fold. In vitro primary neuron culture confirms an intimate contact between neurons and the PEDOT-CNT nanotunnel. During acute in vivo nerve recording, the coated electrode enables the capture of high-fidelity neural signals with low susceptibility to electrical noise and reveals the potential for precisely decoding sensory information through mechanical and thermal stimulation. These findings indicate that the PEDOT-CNT nanotunnel composite serves as an active interfacing material for neural electrodes, contributing to neural prosthesis and brain-machine interface.
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Affiliation(s)
- Nuan Chen
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
- SINAPSE Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore 117456, Singapore
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | - Baiwen Luo
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | - Anoop C Patil
- SINAPSE Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore 117456, Singapore
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | - Jiahui Wang
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
| | | | - Zhigao Yi
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Xiaogang Liu
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Shih-Cheng Yen
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Seeram Ramakrishna
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
| | - Nitish V Thakor
- SINAPSE Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore 117456, Singapore
- The N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
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3
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A 3D-CNT micro-electrode array for zebrafish ECG study including directionality measurement and drug test. Biocybern Biomed Eng 2020. [DOI: 10.1016/j.bbe.2020.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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González‐Sánchez MI, Romero‐Llapa MI, Gómez‐Monedero B, Jiménez‐Pérez R, Iniesta J, Valero E. A Fast and Simple Ozone‐mediated Method towards Highly Activated Screen Printed Carbon Electrodes as Versatile Electroanalytical Tools. ELECTROANAL 2019. [DOI: 10.1002/elan.201900335] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- María Isabel González‐Sánchez
- Department of Physical Chemistry, Higher Technical School of Industrial EngineeringUniversity of Castilla-La Mancha, Campus Universitario s/n 02071 Albacete Spain
| | - María Isabel Romero‐Llapa
- Department of Physical Chemistry, Higher Technical School of Industrial EngineeringUniversity of Castilla-La Mancha, Campus Universitario s/n 02071 Albacete Spain
| | - Beatriz Gómez‐Monedero
- Department of Physical Chemistry, Higher Technical School of Industrial EngineeringUniversity of Castilla-La Mancha, Campus Universitario s/n 02071 Albacete Spain
| | - Rebeca Jiménez‐Pérez
- Department of Physical Chemistry, Higher Technical School of Industrial EngineeringUniversity of Castilla-La Mancha, Campus Universitario s/n 02071 Albacete Spain
| | - Jesús Iniesta
- Department of Physical Chemistry and Institute of ElectrochemistryUniversity of Alicante 03690, San Vicente del Raspeig, Alicante Spain
| | - Edelmira Valero
- Department of Physical Chemistry, Higher Technical School of Industrial EngineeringUniversity of Castilla-La Mancha, Campus Universitario s/n 02071 Albacete Spain
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5
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Zeng Q, Zhao S, Yang H, Zhang Y, Wu T. Micro/Nano Technologies for High-Density Retinal Implant. MICROMACHINES 2019; 10:E419. [PMID: 31234507 PMCID: PMC6630275 DOI: 10.3390/mi10060419] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/14/2019] [Accepted: 06/21/2019] [Indexed: 01/10/2023]
Abstract
During the past decades, there have been leaps in the development of micro/nano retinal implant technologies, which is one of the emerging applications in neural interfaces to restore vision. However, higher feedthroughs within a limited space are needed for more complex electronic systems and precise neural modulations. Active implantable medical electronics are required to have good electrical and mechanical properties, such as being small, light, and biocompatible, and with low power consumption and minimal immunological reactions during long-term implantation. For this purpose, high-density implantable packaging and flexible microelectrode arrays (fMEAs) as well as high-performance coating materials for retinal stimulation are crucial to achieve high resolution. In this review, we mainly focus on the considerations of the high-feedthrough encapsulation of implantable biomedical components to prolong working life, and fMEAs for different implant sites to deliver electrical stimulation to targeted retinal neuron cells. In addition, the functional electrode materials to achieve superior stimulation efficiency are also reviewed. The existing challenge and future research directions of micro/nano technologies for retinal implant are briefly discussed at the end of the review.
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Affiliation(s)
- Qi Zeng
- Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China.
| | - Saisai Zhao
- Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China.
| | - Hangao Yang
- Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China.
| | - Yi Zhang
- Shenzhen CAS-Envision Medical Technology Co. Ltd., Shenzhen 518100, China.
| | - Tianzhun Wu
- Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China.
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6
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Liang Y, Ernst M, Brings F, Kireev D, Maybeck V, Offenhäusser A, Mayer D. High Performance Flexible Organic Electrochemical Transistors for Monitoring Cardiac Action Potential. Adv Healthc Mater 2018; 7:e1800304. [PMID: 30109770 DOI: 10.1002/adhm.201800304] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 04/30/2018] [Indexed: 11/08/2022]
Abstract
Flexible and transparent electronic devices possess crucial advantages over conventional silicon based systems for bioelectronic applications since they are able to adapt to nonplanar surfaces, cause less chronic immunoreactivity, and facilitate easy optical inspection. Here, organic electrochemical transistors (OECTs) are embedded in a flexible matrix of polyimide to record cardiac action potentials. The wafer-scale fabricated devices exhibit transconductances (12 mS V-1 ) and drain-source on-to-off current ratios (≈105 ) comparable to state of the art nonflexible and superior to other reported flexible OECTs. The transfer characteristics of the devices are preserved even after experiencing extremely high bending strain and harsh crumpling. A sub-micrometer poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) layer results in a fast transport of ions between the electrolyte and the polymer channel characterized by a cut-off frequency of 1200 Hz. Excellent device performance is proved by mapping the propagation of cardiac action potentials with high signal-to-noise ratio. These results demonstrate that the electrical performance of flexible OECTs can compete with hard-material-based OECTs and thus potentially be used for in vivo applications.
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Affiliation(s)
- Yuanying Liang
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
| | - Mathis Ernst
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
| | - Fabian Brings
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
| | - Dmitry Kireev
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
| | - Vanessa Maybeck
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
| | - Andreas Offenhäusser
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
| | - Dirk Mayer
- Institute of Complex SystemsBioelectronics (ICS‐8) Forschungszentrum Jülich 52425 Jülich Germany
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7
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Prospects for a Robust Cortical Recording Interface. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00028-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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8
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Koss KM, Churchward MA, Jeffery AF, Mushahwar VK, Elias AL, Todd KG. Improved 3D Hydrogel Cultures of Primary Glial Cells for In Vitro Modelling of Neuroinflammation. J Vis Exp 2017. [PMID: 29286415 DOI: 10.3791/56615] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In the central nervous system, numerous acute injuries and neurodegenerative disorders, as well as implanted devices or biomaterials engineered to enhance function result in the same outcome: excess inflammation leads to gliosis, cytotoxicity, and/or formation of a glial scar that collectively exacerbate injury or prevent healthy recovery. With the intent of creating a system to model glial scar formation and study inflammatory processes, we have generated a 3D cell scaffold capable of housing primary cultured glial cells: microglia that regulate the foreign body response and initiate the inflammatory event, astrocytes that respond to form a fibrous scar, and oligodendrocytes that are typically vulnerable to inflammatory injury. The present work provides a detailed step-by-step method for the fabrication, culture, and microscopic characterization of a hyaluronic acid-based 3D hydrogel scaffold with encapsulated rat brain-derived glial cells. Further, protocols for characterization of cell encapsulation and the hydrogel scaffold by confocal immunofluorescence and scanning electron microscopy are demonstrated, as well as the capacity to modify the scaffold with bioactive substrates, with incorporation of a commercial basal lamina mixture to improved cell integration.
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Affiliation(s)
- Kyle M Koss
- Department of Psychiatry, University of Alberta; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta
| | - Matthew A Churchward
- Department of Psychiatry, University of Alberta; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta
| | - Andrea F Jeffery
- Department of Psychiatry, University of Alberta; Department of Chemical and Materials Engineering, University of Alberta
| | - Vivian K Mushahwar
- Department of Psychiatry, University of Alberta; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta; Division of Physical Medicine and Rehabilitation, University of Alberta
| | - Anastasia L Elias
- Department of Chemical and Materials Engineering, University of Alberta
| | - Kathryn G Todd
- Department of Psychiatry, University of Alberta; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta; Centre for Neuroscience, University of Alberta;
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9
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Chan LLH, Bermak A. Novel structure of carbon nanotube micro electrode for high-resolution stimulation of neurons. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2017; 2016:6170-6173. [PMID: 28269661 DOI: 10.1109/embc.2016.7592137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This paper proposes a novel method to fabricate high resolution flexible electrodes. Among the steps, the carbon nanotube (CNT) electrodes synthesized facing down shows impedance improvement of about 90 times comparing with the normal facing up synthesized samples. Meanwhile, section impedance of electrodes is also defined in this paper to compare the area efficiency of impedance between electrodes with different sizes. In addition and to the best of our knowledge, high performance electrodes embedded inside parylene is reported for the first time taking into consideration the hydrophobicity change of the CNT surface.
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10
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Jeong DW, Kim GH, Kim NY, Lee Z, Jung SD, Lee JO. A high-performance transparent graphene/vertically aligned carbon nanotube (VACNT) hybrid electrode for neural interfacing. RSC Adv 2017. [DOI: 10.1039/c6ra26836f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Transparent graphene-vertically aligned carbon nanotube (VACNT) electrodes enable the dual function of optical cell monitoring and cell electrical signal measurements with exceptionally high signal amplitude.
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Affiliation(s)
- Du Won Jeong
- Advanced Materials Division
- Korea Research Institute of Chemical Technology (KRICT)
- Daejeon 34114
- Korea
| | - Gook Hwa Kim
- Synapse Device Creative Research Section
- Electronics and Telecommunications Research Institute (ETRI)
- Daejeon 34129
- Korea
| | - Na Yeon Kim
- School of Materials Science and Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Korea
| | - Zonghoon Lee
- School of Materials Science and Engineering
- Ulsan National Institute of Science and Technology (UNIST)
- Ulsan 44919
- Korea
| | - Sang Don Jung
- Synapse Device Creative Research Section
- Electronics and Telecommunications Research Institute (ETRI)
- Daejeon 34129
- Korea
| | - Jeong-O. Lee
- Advanced Materials Division
- Korea Research Institute of Chemical Technology (KRICT)
- Daejeon 34114
- Korea
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11
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Zhao L, Chen D, Hu W. Patterning of Metal Films on Arbitrary Substrates by Using Polydopamine as a UV-Sensitive Catalytic Layer for Electroless Deposition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:5285-90. [PMID: 27181020 DOI: 10.1021/acs.langmuir.6b01118] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Patterning metal films on various substrates is essentially important and yet challenging for developing a wide variety of innovative devices. We herein report a versatile approach to pattern metal (gold, silver, or copper) films on arbitrary substrates by using the bio-inspired polydopamine (PDA) thin film as a UV-sensitive adhesive layer for electroless deposition. The PDA film is able to be formed on virtually any solid surfaces under mild condition, and its rich catechol groups allow for electroless deposition of metal films with high adhesion stability. Upon UV irradiation, spatially selective oxidation of PDA film occurs and the local metal deposition is inhibited, thus facilitating successful patterning of metal films. Considering its versatility and simplicity, this strategy may demonstrate great applications in manufacturing various innovative devices.
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Affiliation(s)
- Lei Zhao
- Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy, Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University , Chongqing 400715, China
| | - Daqun Chen
- Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy, Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University , Chongqing 400715, China
| | - Weihua Hu
- Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy, Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University , Chongqing 400715, China
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12
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Shin SR, Farzad R, Tamayol A, Manoharan V, Mostafalu P, Zhang YS, Akbari M, Jung SM, Kim D, Commotto M, Annabi N, Al-Hazmi FE, Dokmeci MR, Khademhosseini A. A Bioactive Carbon Nanotube-Based Ink for Printing 2D and 3D Flexible Electronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:3280-9. [PMID: 26915715 PMCID: PMC4850092 DOI: 10.1002/adma.201506420] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Indexed: 05/21/2023]
Abstract
The development of electrically conductive carbon nanotube-based inks is reported. Using these inks, 2D and 3D structures are printed on various flexible substrates such as paper, hydrogels, and elastomers. The printed patterns have mechanical and electrical properties that make them beneficial for various biological applications.
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Affiliation(s)
- Su Ryon Shin
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Raziyeh Farzad
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ali Tamayol
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Vijayan Manoharan
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Pooria Mostafalu
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Yu Shrike Zhang
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Mohsen Akbari
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Sung Mi Jung
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Duckjin Kim
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mattia Commotto
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Nasim Annabi
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA. Department of Chemical Engineering, Northeastern University, Boston, MA, 02115-5000, USA
| | - Faten Ebrahim Al-Hazmi
- Department of Physics, Department of Chemistry, Fac Sci, Advances Composites Synth & Applicat Grp, King Abdulaziz Univ, Jeddah 21589, Saudi Arabia
| | - Mehmet R. Dokmeci
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Ali Khademhosseini
- Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02139, USA. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA. Department of Physics, Department of Chemistry, Fac Sci, Advances Composites Synth & Applicat Grp, King Abdulaziz Univ, Jeddah 21589, Saudi Arabia
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13
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Pan AI, Lin MH, Chung HW, Chen H, Yeh SR, Chuang YJ, Chang YC, Yew TR. Direct-growth carbon nanotubes on 3D structural microelectrodes for electrophysiological recording. Analyst 2016; 141:279-84. [PMID: 26588673 DOI: 10.1039/c5an01750e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Direct growth of CNTs on 3D microelectrodes could detect distinguished zebrafish ECG resulting from the interfacial improvement analyzed by EIS.
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Affiliation(s)
- Alice Ian Pan
- Department of Materials Science and Engineering
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Min-Hsuan Lin
- Department of Life Sciences
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Hui-Wen Chung
- Department of Life Sciences
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Hsin Chen
- Institute of Electronics Engineering
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Shih-Rung Yeh
- Department of Life Sciences
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Yung-Jen Chuang
- Department of Life Sciences
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Yen-Chung Chang
- Department of Life Sciences
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
| | - Tri-Rung Yew
- Department of Materials Science and Engineering
- National Tsing Hua University
- Hsinchu 30013
- Taiwan
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14
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Yi W, Chen C, Feng Z, Xu Y, Zhou C, Masurkar N, Cavanaugh J, Cheng MMC. A flexible and implantable microelectrode arrays using high-temperature grown vertical carbon nanotubes and a biocompatible polymer substrate. NANOTECHNOLOGY 2015; 26:125301. [PMID: 25742874 DOI: 10.1088/0957-4484/26/12/125301] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This paper presents a novel microelectrode arrays using high-temperature grown vertically aligned carbon nanotubes (CNTs) integrated on a flexible and biocompatible parylene substrate. A simple microfabrication process is proposed to unite the high quality vertical CNTs grown at high temperature with the heat sensitive parylene substrate in a highly controllable manner. Briefly, the CNTs electrode is encapsulated by two layers of parylene and the device is released using xenon difluoride (XeF2). The process is compatible with wafer-scale post complementary metal oxide semiconductor integration. Lower impedance and larger interfacial capacitance have been demonstrated using CNTs compared to a Pt electrode. The flexible CNT electrodes have been utilized for extracellular neuronal recording and stimulation in rats. The signal-to-noise ratio of the device is about 12.5. The threshold voltage for initiating action potential is about 0.5 V.
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Affiliation(s)
- Wenwen Yi
- Electrical and Computer Engineering, Detroit MI USA
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15
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Jorfi M, Skousen JL, Weder C, Capadona JR. Progress towards biocompatible intracortical microelectrodes for neural interfacing applications. J Neural Eng 2014; 12:011001. [PMID: 25460808 DOI: 10.1088/1741-2560/12/1/011001] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
To ensure long-term consistent neural recordings, next-generation intracortical microelectrodes are being developed with an increased emphasis on reducing the neuro-inflammatory response. The increased emphasis stems from the improved understanding of the multifaceted role that inflammation may play in disrupting both biologic and abiologic components of the overall neural interface circuit. To combat neuro-inflammation and improve recording quality, the field is actively progressing from traditional inorganic materials towards approaches that either minimizes the microelectrode footprint or that incorporate compliant materials, bioactive molecules, conducting polymers or nanomaterials. However, the immune-privileged cortical tissue introduces an added complexity compared to other biomedical applications that remains to be fully understood. This review provides a comprehensive reflection on the current understanding of the key failure modes that may impact intracortical microelectrode performance. In addition, a detailed overview of the current status of various materials-based approaches that have gained interest for neural interfacing applications is presented, and key challenges that remain to be overcome are discussed. Finally, we present our vision on the future directions of materials-based treatments to improve intracortical microelectrodes for neural interfacing.
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Affiliation(s)
- Mehdi Jorfi
- Adolphe Merkle Institute, University of Fribourg, Rte de l'Ancienne Papeterie, CH-1723 Marly, Switzerland
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16
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David-Pur M, Bareket-Keren L, Beit-Yaakov G, Raz-Prag D, Hanein Y. All-carbon-nanotube flexible multi-electrode array for neuronal recording and stimulation. Biomed Microdevices 2014; 16:43-53. [PMID: 23974529 PMCID: PMC3921458 DOI: 10.1007/s10544-013-9804-6] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neuro-prosthetic devices aim to restore impaired function through artificial stimulation of the nervous system. A lingering technological bottleneck in this field is the realization of soft, micron sized electrodes capable of injecting enough charge to evoke localized neuronal activity without causing neither electrode nor tissue damage. Direct stimulation with micro electrodes will offer the high efficacy needed in applications such as cochlear and retinal implants. Here we present a new flexible neuronal micro electrode device, based entirely on carbon nanotube technology, where both the conducting traces and the stimulating electrodes consist of conducting carbon nanotube films embedded in a polymeric support. The use of carbon nanotubes bestows the electrodes flexibility and excellent electrochemical properties. As opposed to contemporary flexible neuronal electrodes, the technology presented here is both robust and the resulting stimulating electrodes are nearly purely capacitive. Recording and stimulation tests with chick retinas were used to validate the advantageous properties of the electrodes and demonstrate their suitability for high-efficacy neuronal stimulation applications.
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Affiliation(s)
- Moshe David-Pur
- School of Electrical Engineering, Tel-Aviv University, Tel-Aviv, 6997801, Israel
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17
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Aregueta-Robles UA, Woolley AJ, Poole-Warren LA, Lovell NH, Green RA. Organic electrode coatings for next-generation neural interfaces. FRONTIERS IN NEUROENGINEERING 2014; 7:15. [PMID: 24904405 PMCID: PMC4034607 DOI: 10.3389/fneng.2014.00015] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 05/06/2014] [Indexed: 01/05/2023]
Abstract
Traditional neuronal interfaces utilize metallic electrodes which in recent years have reached a plateau in terms of the ability to provide safe stimulation at high resolution or rather with high densities of microelectrodes with improved spatial selectivity. To achieve higher resolution it has become clear that reducing the size of electrodes is required to enable higher electrode counts from the implant device. The limitations of interfacing electrodes including low charge injection limits, mechanical mismatch and foreign body response can be addressed through the use of organic electrode coatings which typically provide a softer, more roughened surface to enable both improved charge transfer and lower mechanical mismatch with neural tissue. Coating electrodes with conductive polymers or carbon nanotubes offers a substantial increase in charge transfer area compared to conventional platinum electrodes. These organic conductors provide safe electrical stimulation of tissue while avoiding undesirable chemical reactions and cell damage. However, the mechanical properties of conductive polymers are not ideal, as they are quite brittle. Hydrogel polymers present a versatile coating option for electrodes as they can be chemically modified to provide a soft and conductive scaffold. However, the in vivo chronic inflammatory response of these conductive hydrogels remains unknown. A more recent approach proposes tissue engineering the electrode interface through the use of encapsulated neurons within hydrogel coatings. This approach may provide a method for activating tissue at the cellular scale, however, several technological challenges must be addressed to demonstrate feasibility of this innovative idea. The review focuses on the various organic coatings which have been investigated to improve neural interface electrodes.
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Affiliation(s)
| | - Andrew J. Woolley
- Graduate School of Biomedical Engineering, University of New South WalesSydney, NSW, Australia
- School of Medicine, University of Western SydneySydney, NSW, Australia
| | - Laura A. Poole-Warren
- Graduate School of Biomedical Engineering, University of New South WalesSydney, NSW, Australia
| | - Nigel H. Lovell
- Graduate School of Biomedical Engineering, University of New South WalesSydney, NSW, Australia
| | - Rylie A. Green
- Graduate School of Biomedical Engineering, University of New South WalesSydney, NSW, Australia
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18
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Fattahi P, Yang G, Kim G, Abidian MR. A review of organic and inorganic biomaterials for neural interfaces. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:1846-85. [PMID: 24677434 PMCID: PMC4373558 DOI: 10.1002/adma.201304496] [Citation(s) in RCA: 300] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 10/08/2013] [Indexed: 05/18/2023]
Abstract
Recent advances in nanotechnology have generated wide interest in applying nanomaterials for neural prostheses. An ideal neural interface should create seamless integration into the nervous system and performs reliably for long periods of time. As a result, many nanoscale materials not originally developed for neural interfaces become attractive candidates to detect neural signals and stimulate neurons. In this comprehensive review, an overview of state-of-the-art microelectrode technologies provided fi rst, with focus on the material properties of these microdevices. The advancements in electro active nanomaterials are then reviewed, including conducting polymers, carbon nanotubes, graphene, silicon nanowires, and hybrid organic-inorganic nanomaterials, for neural recording, stimulation, and growth. Finally, technical and scientific challenges are discussed regarding biocompatibility, mechanical mismatch, and electrical properties faced by these nanomaterials for the development of long-lasting functional neural interfaces.
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Affiliation(s)
- Pouria Fattahi
- Biomedical Engineering Department and Chemical Engineering Departments, Pennsylvania State University, University Park, PA, 16802, USA
| | - Guang Yang
- Biomedical Engineering Department, Pennsylvania State University, University Park, PA, 16802, USA
| | - Gloria Kim
- Biomedical Engineering Department, Pennsylvania State University, University Park, PA, 16802, USA
| | - Mohammad Reza Abidian
- Biomedical Engineering Department, Materials Science & Engineering Department, Chemical Engineering Department, Materials Research Institute, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, 16802, USA
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19
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Robert-Nicoud G, Donno R, Cadman CJ, Alexander MR, Tirelli N. Surface modification of silicone via colloidal deposition of amphiphilic block copolymers. Polym Chem 2014. [DOI: 10.1039/c4py00941j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Bareket-Keren L, Hanein Y. Carbon nanotube-based multi electrode arrays for neuronal interfacing: progress and prospects. Front Neural Circuits 2013; 6:122. [PMID: 23316141 PMCID: PMC3540767 DOI: 10.3389/fncir.2012.00122] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 12/22/2012] [Indexed: 12/17/2022] Open
Abstract
Carbon nanotube (CNT) coatings have been demonstrated over the past several years as a promising material for neuronal interfacing applications. In particular, in the realm of neuronal implants, CNTs have major advantages owing to their unique mechanical and electrical properties. Here we review recent investigations utilizing CNTs in neuro-interfacing applications. Cell adhesion, neuronal engineering and multi electrode recordings with CNTs are described. We also highlight prospective advances in this field, in particular, progress toward flexible, bio-compatible CNT-based technology.
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Affiliation(s)
- Lilach Bareket-Keren
- School of Electrical Engineering, Tel-Aviv UniversityTel-Aviv, Israel
- Tel-Aviv University Center for Nanoscience and Nanotechnology, Tel-Aviv UniversityTel-Aviv, Israel
| | - Yael Hanein
- School of Electrical Engineering, Tel-Aviv UniversityTel-Aviv, Israel
- Tel-Aviv University Center for Nanoscience and Nanotechnology, Tel-Aviv UniversityTel-Aviv, Israel
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21
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Chang YT, Huang JH, Tu MC, Chang P, Yew TR. Flexible direct-growth CNT biosensors. Biosens Bioelectron 2012; 41:898-902. [PMID: 23083911 DOI: 10.1016/j.bios.2012.09.049] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/23/2012] [Accepted: 09/25/2012] [Indexed: 01/06/2023]
Abstract
A biosensor was fabricated by growing carbon nanotubes (CNTs) directly on a polyimide flexible substrate at low temperatures (≤400 °C). A biocompatible polymer (poly(para-xylylene), parylene) was subsequently coated on the surface without CNTs as an insulator for future applications of flexible biosensors in in vivo sensing. The feasibility of the CNT flexible biosensor was demonstrated by quantitatively detecting human serum albumin (HSA). The CNT surface was modified with functional groups using UV-ozone, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), and treated with N-hydroxysuccinimide (NHS) to improve the biocompatibility for the conjugation of protein. In addition, anti-HSA (AHSA) was used to capture HSA specifically, and bovine serum albumin (BSA) was applied to block the non-specific sites. The electrical properties of the biosensors applied with various HSA concentrations were measured and quantified using an electrochemical impedance spectroscopy system under AC conditions. The detection limit of the biosensor for HSA detection was approximately 3×10(-11) mg/ml. The proposed sensor has considerable potential for future application in wearable biosensors and implant detection.
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Affiliation(s)
- Yun-Tzu Chang
- National Tsing Hua University, Department of Materials Science and Engineering, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
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22
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Musa S, Rand DR, Cott DJ, Loo J, Bartic C, Eberle W, Nuttin B, Borghs G. Bottom-up SiO2 embedded carbon nanotube electrodes with superior performance for integration in implantable neural microsystems. ACS NANO 2012; 6:4615-4628. [PMID: 22551016 DOI: 10.1021/nn201609u] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The reliable integration of carbon nanotube (CNT) electrodes in future neural probes requires a proper embedding of the CNTs to prevent damage and toxic contamination during fabrication and also to preserve their mechanical integrity during implantation. Here we describe a novel bottom-up embedding approach where the CNT microelectrodes are encased in SiO(2) and Parylene C with lithographically defined electrode openings. Vertically aligned CNTs are grown on microelectrode arrays using low-temperature plasma-enhanced chemical vapor deposition compatible with wafer-scale CMOS processing. Electrodes with 5, 10, and 25 μm diameter are realized. The CNT electrodes are characterized by electrochemical impedance spectroscopy and cyclic voltammetry and compared against cofabricated Pt and TiN electrodes. The superior performance of the CNTs in terms of impedance (≤4.8 ± 0.3 kΩ at 1 kHz) and charge-storage capacity (≥513.9 ± 61.6 mC/cm(2)) is attributed to an increased wettability caused by the removal of the SiO(2) embedding in buffered hydrofluoric acid. Infrared spectroscopy reveals an unaltered chemical fingerprint of the CNTs after fabrication. Impedance monitoring during biphasic current pulsing with increasing amplitudes provides clear evidence of the onset of gas evolution at CNT electrodes. Stimulation is accordingly considered safe for charge densities ≤40.7 mC/cm(2). In addition, prolonged stimulation with 5000 biphasic current pulses at 8.1, 40.7, and 81.5 mC/cm(2) increases the CNT electrode impedance at 1 kHz only by 5.5, 1.2, and 12.1%, respectively. Finally, insertion of CNT electrodes with and without embedding into rat brains demonstrates that embedded CNTs are mechanically more stable than non-embedded CNTs.
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Affiliation(s)
- Silke Musa
- Imec, Kapeldreef 75, 3001 Heverlee, Belgium.
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23
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Lee YT, Yeh SR, Chang YC, Fang W. Integration of silicon-via electrodes with different recording characteristics on a glass microprobe using a glass reflowing process. Biosens Bioelectron 2011; 26:4739-46. [PMID: 21696942 DOI: 10.1016/j.bios.2011.05.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 05/18/2011] [Accepted: 05/25/2011] [Indexed: 11/19/2022]
Abstract
Electrodes on planar type microelectromechanical system (MEMS) microprobes mainly record neurons on the top-side of probe shaft (called a top-side electrode). However, it is often necessary to record neurons other than those on the top-side of the probe shaft. This study uses the glass reflowing technique to embed silicon-vias in a glass probe to implement a microprobe capable of recording neurons around the shaft. The proposed technology makes it possible to fabricate, distribute, and integrate four types of electrodes on the shaft: top-side, back-side, double-side, and sidewall electrodes. These electrodes have different recording characteristics. The in vitro and in vivo (using crayfish and rat brain) experiments in this study shows that the top-side and back-side electrodes are respectively more sensitive to neurons on the top-side and back-side of the probe shaft. In contrast, signals recorded by double-side electrode and sidewall electrode are equally sensitive to neurons around the probe shaft. This study enables the implementation and integration of these four types of electrodes, meeting the requirements of various neural applications.
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Affiliation(s)
- Yu-Tao Lee
- Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu, Taiwan
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24
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Chen YC, Hsu HL, Lee YT, Su HC, Yen SJ, Chen CH, Hsu WL, Yew TR, Yeh SR, Yao DJ, Chang YC, Chen H. An active, flexible carbon nanotube microelectrode array for recording electrocorticograms. J Neural Eng 2011; 8:034001. [PMID: 21474876 DOI: 10.1088/1741-2560/8/3/034001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A variety of microelectrode arrays (MEAs) has been developed for monitoring intra-cortical neural activity at a high spatio-temporal resolution, opening a promising future for brain research and neural prostheses. However, most MEAs are based on metal electrodes on rigid substrates, and the intra-cortical implantation normally causes neural damage and immune responses that impede long-term recordings. This communication presents a flexible, carbon-nanotube MEA (CMEA) with integrated circuitry. The flexibility allows the electrodes to fit on the irregular surface of the brain to record electrocorticograms in a less invasive way. Carbon nanotubes (CNTs) further improve both the electrode impedance and the charge-transfer capacity by more than six times. Moreover, the CNTs are grown on the polyimide substrate directly to improve the adhesion to the substrate. With the integrated recording circuitry, the flexible CMEA is proved capable of recording the neural activity of crayfish in vitro, as well as the electrocorticogram of a rat cortex in vivo, with an improved signal-to-noise ratio. Therefore, the proposed CMEA can be employed as a less-invasive, biocompatible and reliable neuro-electronic interface for long-term usage.
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Affiliation(s)
- Yung-Chan Chen
- Institute of Electronics Engineering, National Tsing Hua University (NTHU), No 101, Sec. 2, Kuang-Fu Rd, Hsinchu 30013, Taiwan
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