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Dragas J, Viswam V, Shadmani A, Chen Y, Bounik R, Stettler A, Radivojevic M, Geissler S, Obien M, Müller J, Hierlemann A. A Multi-Functional Microelectrode Array Featuring 59760 Electrodes, 2048 Electrophysiology Channels, Stimulation, Impedance Measurement and Neurotransmitter Detection Channels. IEEE JOURNAL OF SOLID-STATE CIRCUITS 2017; 52:1576-1590. [PMID: 28579632 PMCID: PMC5447818 DOI: 10.1109/jssc.2017.2686580] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Biological cells are characterized by highly complex phenomena and processes that are, to a great extent, interdependent. To gain detailed insights, devices designed to study cellular phenomena need to enable tracking and manipulation of multiple cell parameters in parallel; they have to provide high signal quality and high spatiotemporal resolution. To this end, we have developed a CMOS-based microelectrode array system that integrates six measurement and stimulation functions, the largest number to date. Moreover, the system features the largest active electrode array area to date (4.48×2.43 mm2) to accommodate 59,760 electrodes, while its power consumption, noise characteristics, and spatial resolution (13.5 μm electrode pitch) are comparable to the best state-of-the-art devices. The system includes: 2,048 action-potential (AP, bandwidth: 300 Hz to 10 kHz) recording units, 32 local-field-potential (LFP, bandwidth: 1 Hz to 300 Hz) recording units, 32 current recording units, 32 impedance measurement units, and 28 neurotransmitter detection units, in addition to the 16 dual-mode voltage-only or current/voltage-controlled stimulation units. The electrode array architecture is based on a switch matrix, which allows for connecting any measurement/stimulation unit to any electrode in the array and for performing different measurement/stimulation functions in parallel.
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Affiliation(s)
- Jelena Dragas
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Vijay Viswam
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Amir Shadmani
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Yihui Chen
- ETH Zurich, D-BSSE, 4058 Basel, Switzerland, and now is with Analog Devices Shanghai Co. Ltd., Shanghai, China
| | - Raziyeh Bounik
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Alexander Stettler
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Milos Radivojevic
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Sydney Geissler
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Marie Obien
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Jan Müller
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
| | - Andreas Hierlemann
- ETH Zurich, Department of Biosystems Science and Engineering (D-BSSE), 4058 Basel, Switzerland
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Jonczyk R, Kurth T, Lavrentieva A, Walter JG, Scheper T, Stahl F. Living Cell Microarrays: An Overview of Concepts. MICROARRAYS (BASEL, SWITZERLAND) 2016; 5:E11. [PMID: 27600077 PMCID: PMC5003487 DOI: 10.3390/microarrays5020011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/09/2016] [Accepted: 05/11/2016] [Indexed: 02/06/2023]
Abstract
Living cell microarrays are a highly efficient cellular screening system. Due to the low number of cells required per spot, cell microarrays enable the use of primary and stem cells and provide resolution close to the single-cell level. Apart from a variety of conventional static designs, microfluidic microarray systems have also been established. An alternative format is a microarray consisting of three-dimensional cell constructs ranging from cell spheroids to cells encapsulated in hydrogel. These systems provide an in vivo-like microenvironment and are preferably used for the investigation of cellular physiology, cytotoxicity, and drug screening. Thus, many different high-tech microarray platforms are currently available. Disadvantages of many systems include their high cost, the requirement of specialized equipment for their manufacture, and the poor comparability of results between different platforms. In this article, we provide an overview of static, microfluidic, and 3D cell microarrays. In addition, we describe a simple method for the printing of living cell microarrays on modified microscope glass slides using standard DNA microarray equipment available in most laboratories. Applications in research and diagnostics are discussed, e.g., the selective and sensitive detection of biomarkers. Finally, we highlight current limitations and the future prospects of living cell microarrays.
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Affiliation(s)
- Rebecca Jonczyk
- Institute of Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, Hannover 30167, Germany.
| | - Tracy Kurth
- Institute of Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, Hannover 30167, Germany.
| | - Antonina Lavrentieva
- Institute of Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, Hannover 30167, Germany.
| | - Johanna-Gabriela Walter
- Institute of Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, Hannover 30167, Germany.
| | - Thomas Scheper
- Institute of Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, Hannover 30167, Germany.
| | - Frank Stahl
- Institute of Technical Chemistry, Leibniz University of Hannover, Callinstr. 5, Hannover 30167, Germany.
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Rolston JD, Gross RE, Potter SM. Closed-loop, open-source electrophysiology. Front Neurosci 2010; 4. [PMID: 20859448 PMCID: PMC2940414 DOI: 10.3389/fnins.2010.00031] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2010] [Accepted: 05/11/2010] [Indexed: 11/25/2022] Open
Abstract
Multiple extracellular microelectrodes (multi-electrode arrays, or MEAs) effectively record rapidly varying neural signals, and can also be used for electrical stimulation. Multi-electrode recording can serve as artificial output (efferents) from a neural system, while complex spatially and temporally targeted stimulation can serve as artificial input (afferents) to the neuronal network. Multi-unit or local field potential (LFP) recordings can not only be used to control real world artifacts, such as prostheses, computers or robots, but can also trigger or alter subsequent stimulation. Real-time feedback stimulation may serve to modulate or normalize aberrant neural activity, to induce plasticity, or to serve as artificial sensory input. Despite promising closed-loop applications, commercial electrophysiology systems do not yet take advantage of the bidirectional capabilities of multi-electrodes, especially for use in freely moving animals. We addressed this lack of tools for closing the loop with NeuroRighter, an open-source system including recording hardware, stimulation hardware, and control software with a graphical user interface. The integrated system is capable of multi-electrode recording and simultaneous patterned microstimulation (triggered by recordings) with minimal stimulation artifact. The potential applications of closed-loop systems as research tools and clinical treatments are broad; we provide one example where epileptic activity recorded by a multi-electrode probe is used to trigger targeted stimulation, via that probe, to freely moving rodents.
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Affiliation(s)
- John D Rolston
- Laboratory for Neuroengineering, Georgia Institute of Technology and Emory University School of Medicine Atlanta, GA, USA
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Desai SA, Rolston JD, Guo L, Potter SM. Improving impedance of implantable microwire multi-electrode arrays by ultrasonic electroplating of durable platinum black. FRONTIERS IN NEUROENGINEERING 2010; 3:5. [PMID: 20485478 PMCID: PMC2871717 DOI: 10.3389/fneng.2010.00005] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2009] [Accepted: 04/07/2010] [Indexed: 12/03/2022]
Abstract
Implantable microelectrode arrays (MEAs) have been a boon for neural stimulation and recording experiments. Commercially available MEAs have high impedances, due to their low surface area and small tip diameters, which are suitable for recording single unit activity. Lowering the electrode impedance, but preserving the small diameter, would provide a number of advantages, including reduced stimulation voltages, reduced stimulation artifacts and improved signal-to-noise ratio. Impedance reductions can be achieved by electroplating the MEAs with platinum (Pt) black, which increases the surface area but has little effect on the physical extent of the electrodes. However, because of the low durability of Pt black plating, this method has not been popular for chronic use. Sonicoplating (i.e. electroplating under ultrasonic agitation) has been shown to improve the durability of Pt black on the base metals of macro-electrodes used for cyclic voltammetry. This method has not previously been characterized for MEAs used in chronic neural implants. We show here that sonicoplating can lower the impedances of microwire multi-electrode arrays (MMEA) by an order of magnitude or more (depending on the time and voltage of electroplating), with better durability compared to pulsed plating or traditional DC methods. We also show the improved stimulation and recording performance that can be achieved in an in vivo implantation study with the sonicoplated low-impedance MMEAs, compared to high-impedance unplated electrodes.
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Affiliation(s)
- Sharanya Arcot Desai
- Laboratory for Neuroengineering, The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology Atlanta, GA, USA
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Brown EA, Ross JD, Blum RA, Wheeler BC, Deweerth SP. Stimulus-artifact elimination in a multi-electrode system. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2008; 2:10-21. [PMID: 23852629 DOI: 10.1109/tbcas.2008.918285] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
To fully exploit the recording capabilities provided by current and future generations of multi-electrode arrays, some means to eliminate the residual charge and subsequent artifacts generated by stimulation protocols is required. Custom electronics can be used to achieve such goals, and by making them scalable, a large number of electrodes can be accessed in an experiment. In this work, we present a system built around a custom 16-channel IC that can stimulate and record, within 3 ms of the stimulus, on the stimulating channel, and within 500 mus on adjacent channels. This effectiveness is achieved by directly discharging the electrode through a novel feedback scheme, and by shaping such feedback to optimize electrode behavior. We characterize the different features of the system that makes such performance possible and present biological data that show the system in operation. To enable this characterization, we present a framework for measuring, classifying, and understanding the multiple sources of stimulus artifacts. This framework facilitates comparisons between artifact elimination methodologies and enables future artifact studies.
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Zhong Y, Bellamkonda RV. Controlled release of anti-inflammatory agent alpha-MSH from neural implants. J Control Release 2005; 106:309-18. [PMID: 15978692 DOI: 10.1016/j.jconrel.2005.05.012] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Revised: 05/05/2005] [Accepted: 05/05/2005] [Indexed: 11/22/2022]
Abstract
Si-multi-electrode arrays implanted into brain tissue for long-term recording lose electrical connectivity due to the post-implantation inflammatory reaction. This inflammatory reaction creates a physical and electrical gap between the electrode and the surrounding neurons. In this study, novel nitrocellulose-based coatings were developed for the sustained delivery of the anti-inflammatory neuropeptide alpha-melanocyte stimulating hormone (alpha-MSH). alpha-MSH was incorporated in micron-scale nitrocellulose coatings and slow, sustained release over 21 days was attained in vitro. The alpha-MSH released on day 21 was still bioactive, and successfully inhibited nitric oxide (NO) production by LPS-stimulated microglia. The amount of initial drug loading directly affected the release rate, with higher initial loading increasing the mass released but not the percent of drug released. The surface morphology and thickness of the coatings were examined by scanning electron microscopy (SEM) and profilometry. In addition, impedance measurement showed that the alpha-MSH loaded nitrocellulose coatings reduced the magnitude of electrode impedance at the biologically relevant frequency of 1 kHz. In conclusion, nitrocellulose-based, bioactive coatings that release anti-inflammatory agents without increasing the impedence of the electrode were successfully fabricated. These coatings have the potential to reduce inflammation at the electrode-brain interface in vivo, and facilitate long-term recordings from Si-multi-electrode arrays.
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Affiliation(s)
- Yinghui Zhong
- Neurological Biomaterials and Therapeutics, Laboratory for Neuroengineering, Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, GA 30332-0535, USA
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He W, Bellamkonda RV. Nanoscale neuro-integrative coatings for neural implants. Biomaterials 2005; 26:2983-90. [PMID: 15603793 DOI: 10.1016/j.biomaterials.2004.08.021] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2004] [Accepted: 08/17/2004] [Indexed: 10/26/2022]
Abstract
Silicon microelectrode arrays (Si MEAs) have great potential in enabling chronic in vivo recording of neural activity, but this potential has been hampered by scar tissue formation at the site of implantation. In this study, we report the fabrication and characterization of nanoscale coatings that have the potential of enhancing the biocompatibility of Si electrodes. We use electrostatic layer-by-layer (LbL) assembly to prepare nanoscale bioactive coatings on silicon substrates. We use the response of chick cortical neurons to these coatings to assess potential improvement in biocompatibility in vitro. The coatings are built on oxide covered silicon wafers by alternating polycations, polyethyleneimine (PEI) or chitosan (CH), with polyanions, either gelatin or laminin (LN). We use quartz crystal microbalance (QCM) to characterize the coatings. Our analysis confirms that we achieved approximately 30-110 angstroms scale coatings via LbL assembly. In contrast to bare oxide covered silicon, coated substrates had significantly enhanced chick cortical neuron adhesion and differentiation, with multilayers of PEI-LN showing the greatest improvement. The multilayers of PEI-LN were stable for at least 7 days in physiological conditions, as determined by an enzyme-linked immunosorbent assay (ELISA). In addition, impedance spectroscopy confirmed that multilayers of PEI and LN did not increase the magnitude of impedance of Si MEAs at the biologically relevant frequency of 1 kHz. Our study demonstrates that electrostatic LbL assembly enables nanoscale bioactive coatings, and that PEI-LN multilayers significantly enhance cortical neuronal attachment and differentiation in vitro with no deleterious effects on impedance of the electrodes. Such well-controlled nanoscale coatings have the potential to significantly impact the compatibility and performance of Si MEAs in vivo.
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Affiliation(s)
- Wei He
- Neurological Biomaterials and Therapeutics, Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 313 Ferst Dr., Atlanta, GA 30332, USA
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