1
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Mintz Hemed N, Hwang FJ, Zhao ET, Ding JB, Melosh NA. Multiplexed neurochemical sensing with sub-nM sensitivity across 2.25 mm 2 area. Biosens Bioelectron 2024; 261:116474. [PMID: 38870827 DOI: 10.1016/j.bios.2024.116474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/20/2024] [Accepted: 06/05/2024] [Indexed: 06/15/2024]
Abstract
Multichannel arrays capable of real-time sensing of neuromodulators in the brain are crucial for gaining insights into new aspects of neural communication. However, measuring neurochemicals, such as dopamine, at low concentrations over large areas has proven challenging. In this research, we demonstrate a novel approach that leverages the scalability and processing power offered by microelectrode array devices integrated with a functionalized, high-density microwire bundle, enabling electrochemical sensing at an unprecedented scale and spatial resolution. The sensors demonstrate outstanding selective molecular recognition by incorporating a selective polymeric membrane. By combining cutting-edge commercial multiplexing, digitization, and data acquisition hardware with a bio-compatible and highly sensitive neurochemical interface array, we establish a powerful platform for neurochemical analysis. This multichannel array has been successfully utilized in vitro and ex vivo systems. Notably, our results show a sensing area of 2.25 mm2 with an impressive detection limit of 820 pM for dopamine. This new approach paves the way for investigating complex neurochemical processes and holds promise for advancing our understanding of brain function and neurological disorders.
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Affiliation(s)
- Nofar Mintz Hemed
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Fuu-Jiun Hwang
- Department of Neurosurgery, Stanford University, Stanford, CA, 94305, USA
| | - Eric T Zhao
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Jun B Ding
- Department of Neurosurgery, Stanford University, Stanford, CA, 94305, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Nicholas A Melosh
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
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2
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Meng L, Akhoundian M, Al Azawi A, Shoja Y, Chi PY, Meinander K, Suihkonen S, Franssila S. Ultrasensitive Monolithic Dopamine Microsensors Employing Vertically Aligned Carbon Nanofibers. Adv Healthc Mater 2024:e2303872. [PMID: 38837670 DOI: 10.1002/adhm.202303872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/19/2024] [Indexed: 06/07/2024]
Abstract
Brain-on-Chip devices, which facilitate on-chip cultures of neurons to simulate brain functions, are receiving tremendous attention from both fundamental and clinical research. Consequently, microsensors are being developed to accomplish real-time monitoring of neurotransmitters, which are the benchmarks for neuron network operation. Among these, electrochemical sensors have emerged as promising candidates for detecting a critical neurotransmitter, dopamine. However, current state-of-the-art electrochemical dopamine sensors are suffering from issues like limited sensitivity and cumbersome fabrication. Here, a novel route in monolithically microfabricating vertically aligned carbon nanofiber electrochemical dopamine microsensors is reported with an anti-blistering slow cooling process. Thanks to the microfabrication process, microsensors is created with complete insulation and large surface areas. The champion device shows extremely high sensitivity of 4.52× 104 µAµM-1·cm-2, which is two-orders-of-magnitude higher than current devices, and a highly competitive limit of detection of 0.243 nM. These remarkable figures-of-merit will open new windows for applications such as electrochemical recording from a single neuron.
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Affiliation(s)
- Lingju Meng
- Department of Chemistry and Materials Science, Aalto University, Espoo, 02150, Finland
- Micronova Nanofabrication Centre, Aalto University, Espoo, 02150, Finland
| | - Maedeh Akhoundian
- Department of Electrical Engineering and Automation, Aalto University, Espoo, 02150, Finland
| | - Anas Al Azawi
- Department of Chemistry and Materials Science, Aalto University, Espoo, 02150, Finland
- Micronova Nanofabrication Centre, Aalto University, Espoo, 02150, Finland
| | - Yalda Shoja
- Department of Chemistry and Materials Science, Aalto University, Espoo, 02150, Finland
- Micronova Nanofabrication Centre, Aalto University, Espoo, 02150, Finland
| | - Pei-Yin Chi
- Department of Chemistry and Materials Science, Aalto University, Espoo, 02150, Finland
- Micronova Nanofabrication Centre, Aalto University, Espoo, 02150, Finland
| | - Kristoffer Meinander
- Department of Bioproducts and Biosystems, Aalto University, Espoo, 02150, Finland
| | - Sami Suihkonen
- Department of Electronics and Nanoengineering, Aalto University, Espoo, 02150, Finland
| | - Sami Franssila
- Department of Chemistry and Materials Science, Aalto University, Espoo, 02150, Finland
- Micronova Nanofabrication Centre, Aalto University, Espoo, 02150, Finland
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3
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Pankratova G, Pan JY, Keller SS. Impact of plasma-induced surface chemistry on electrochemical properties of microfabricated pyrolytic carbon electrodes. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.139987] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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In situ graphene-modified carbon microelectrode array biosensor for biofilm impedance analysis. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2021.139570] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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Lucio Boschen S, Trevathan J, Hara SA, Asp A, Lujan JL. Defining a Path Toward the Use of Fast-Scan Cyclic Voltammetry in Human Studies. Front Neurosci 2021; 15:728092. [PMID: 34867151 PMCID: PMC8633532 DOI: 10.3389/fnins.2021.728092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 10/25/2021] [Indexed: 11/13/2022] Open
Abstract
Fast Scan Cyclic Voltammetry (FSCV) has been used for decades as a neurochemical tool for in vivo detection of phasic changes in electroactive neurotransmitters in animal models. Recently, multiple research groups have initiated human neurochemical studies using FSCV or demonstrated interest in bringing FSCV into clinical use. However, there remain technical challenges that limit clinical implementation of FSCV by creating barriers to appropriate scientific rigor and patient safety. In order to progress with clinical FSCV, these limitations must be first addressed through (1) appropriate pre-clinical studies to ensure accurate measurement of neurotransmitters and (2) the application of a risk management framework to assess patient safety. The intent of this work is to bring awareness of the current issues associated with FSCV to the scientific, engineering, and clinical communities and encourage them to seek solutions or alternatives that ensure data accuracy, rigor and reproducibility, and patient safety.
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Affiliation(s)
- Suelen Lucio Boschen
- Applied Computational Neurophysiology and Neuromodulation Laboratory, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States
| | - James Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
| | - Seth A Hara
- Division of Engineering, Mayo Clinic, Rochester, MN, United States
| | - Anders Asp
- Applied Computational Neurophysiology and Neuromodulation Laboratory, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN, United States
| | - J Luis Lujan
- Applied Computational Neurophysiology and Neuromodulation Laboratory, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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6
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Nimbalkar S, Samejima S, Dang V, Hunt T, Nunez O, Moritz C, Kassegne S. Graphene on glassy carbon microelectrodes demonstrate long-term structural and functional stability in neurophysiological recording and stimulation. J Neural Eng 2021; 18. [PMID: 34492644 DOI: 10.1088/1741-2552/ac245a] [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: 05/20/2021] [Accepted: 09/07/2021] [Indexed: 11/12/2022]
Abstract
Objective.There is a growing interest in the use of carbon and its allotropes for microelectrodes in neural probes because of their inertness, long-term electrical and electrochemical stability, and versatility. Building on this interest, we introduce a new electrode material system consisting of an ultra-thin monoatomic layer of graphene (Gr) mechanically supported by a relatively thicker layer of glassy carbon (GC).Approach.Due to its high electrical conductivity and high double-layer capacitance, Gr has impressive electrical and electrochemical properties, two key properties that are useful for neural recording and stimulation applications. However, because of its two-dimensional nature, Gr exhibits a lack of stiffness in the transverse direction and hence almost non-existent flexural and out-of-plane rigidity that will severely limit its wider use. On the other hand, GC is one of carbon's important allotropes and consists of three-dimensional microstructures of Gr fragments with a natural molecular similarity to Gr. Further, GC has exceptional chemical inertness, good electrical properties, high electrochemical stability, purely capacitive charge injection, and fast surface electrokinetics coupled with lithography patternability. This makes GC an ideal candidate for addressing Gr's lack of out-of-plane rigidity through providing a matching sturdier and robust mechanical backing. Combining the strengths of these two allotropes of carbon, we introduce a new neural probe that consists of ∼1 nm thick layer of patterned Gr microelectrodes supported by another layer of 3-5μm thick patterned GC.Main results. We present the fabrication technology for the newGr on GC(graphene on glassy carbon) microelectrodes and the accompanying pattern transfer technology on flexible substrate and report on the bond between these two allotropes of carbon through FTIR, surface morphology through SEM, topography through atomic force microscopy, and microstructure imaging through scanning transmission electron microscopy. A long-term (18 weeks)in vivostudy of the use of theseGr on GCmicroelectrodes assessed the quality of the electrocorticography-based neural signal recording and stimulation through electrophysiological measurements. The probes were demonstrated to be functionally and structurally stable over the 18 week period with minimal glial response-the longest reported so far for Gr-based microelectrodes.Significance.TheGr on GCmicroelectrodes presented here offers a compelling case for expanding the potentials of Gr-based technology in the broad areas of neural probes.
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Affiliation(s)
- Surabhi Nimbalkar
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
| | - Soshi Samejima
- Departments of Electrical & Computer Engineering, and Rehabilitation Medicine, University of Washington, Seattle, WA, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
| | - Viet Dang
- Departments of Electrical & Computer Engineering, and Rehabilitation Medicine, University of Washington, Seattle, WA, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
| | - Trevor Hunt
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
| | - Omar Nunez
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
| | - Chet Moritz
- Departments of Electrical & Computer Engineering, and Rehabilitation Medicine, University of Washington, Seattle, WA, United States of America.,Departments of Physiology Biophysics, University of Washington, Seattle, WA, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
| | - Sam Kassegne
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States of America.,NSF-ERC Center for Neurotechnology (CNT), Seattle, WA 98195, United States of America
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7
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Leroy A, Teixidor J, Bertsch A, Renaud P. In-flow electrochemical detection of chemicals in droplets with pyrolysed photoresist electrodes: application as a module for quantification of microsampled dopamine. LAB ON A CHIP 2021; 21:3328-3337. [PMID: 34250532 DOI: 10.1039/d1lc00116g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The electrochemical quantification of analytes in droplets of PBS separated by a fluorinated phase was investigated. PDMS-fused silica chips with pyrolysed photoresist electrodes were prepared using a simple fabrication technique and used to analyze droplets in flow. Potentiostatic chronoamperometry provided current readouts consistent with mass transport and the concentration inside the droplets. This paper highlights measurements of dopamine in droplets in T-junction microfluidic chips at unprecedently low concentrations, with a limit of detection of 207 nM and a linear range of 0.21-20 μM, giving results similar to continuous flow electrochemistry and allowing the analysis in the striatal extracellular range (<1 μM). The system was applied to the quick and reliable on-line detection of dopamine concentration steps in droplets collected with a microsampling probe in vitro, demonstrating the usefulness of the electrochemical device as a quantification module for microsampled chemicals in droplets.
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Affiliation(s)
- Albert Leroy
- EPFL-STI-IMT-LMIS4, École Polytechnique Fédérale de Lausanne, Station 17, CH-1015 Lausanne, Switzerland.
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8
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Kang YN, Chou N, Jang JW, Choe HK, Kim S. A 3D flexible neural interface based on a microfluidic interconnection cable capable of chemical delivery. MICROSYSTEMS & NANOENGINEERING 2021; 7:66. [PMID: 34567778 PMCID: PMC8433186 DOI: 10.1038/s41378-021-00295-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/23/2021] [Accepted: 07/11/2021] [Indexed: 05/23/2023]
Abstract
The demand for multifunctional neural interfaces has grown due to the need to provide a better understanding of biological mechanisms related to neurological diseases and neural networks. Direct intracerebral drug injection using microfluidic neural interfaces is an effective way to deliver drugs to the brain, and it expands the utility of drugs by bypassing the blood-brain barrier (BBB). In addition, uses of implantable neural interfacing devices have been challenging due to inevitable acute and chronic tissue responses around the electrodes, pointing to a critical issue still to be overcome. Although neural interfaces comprised of a collection of microneedles in an array have been used for various applications, it has been challenging to integrate microfluidic channels with them due to their characteristic three-dimensional structures, which differ from two-dimensionally fabricated shank-type neural probes. Here we present a method to provide such three-dimensional needle-type arrays with chemical delivery functionality. We fabricated a microfluidic interconnection cable (µFIC) and integrated it with a flexible penetrating microelectrode array (FPMA) that has a 3-dimensional structure comprised of silicon microneedle electrodes supported by a flexible array base. We successfully demonstrated chemical delivery through the developed device by recording neural signals acutely from in vivo brains before and after KCl injection. This suggests the potential of the developed microfluidic neural interface to contribute to neuroscience research by providing simultaneous signal recording and chemical delivery capabilities.
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Affiliation(s)
- Yoo Na Kang
- Department of Medical Assistant Robot, Korea Institute of Machinery & Materials (KIMM), Daegu, Republic of Korea
| | - Namsun Chou
- Center for BioMicrosystems, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Jae-Won Jang
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Han Kyoung Choe
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Sohee Kim
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
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9
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Xia D, Hang D, Li Y, Jiang W, Zhu J, Ding Y, Gu H, Hu Y. Au-Hemoglobin Loaded Platelet Alleviating Tumor Hypoxia and Enhancing the Radiotherapy Effect with Low-Dose X-ray. ACS NANO 2020; 14:15654-15668. [PMID: 33108152 DOI: 10.1021/acsnano.0c06541] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Radiotherapy (RT) is a widely explored clinical modality to combat cancer. However, its therapeutic efficacy is not always satisfied because of the severe hypoxic microenvironment in solid tumors and the high dosage of radiation harmful to the adjacent healthy tissue. Herein, Au nanoparticle-hemoglobin complex nanoparticle loaded platelets (Au-Hb@PLT) were fabricated. These Au-Hb@PLT would be activated by tumor cells, and the formed platelet-derivate particles (PM) could deliver Au nanoparticle-hemoglobin complex deeply into tumor tissue because of their small size and tumor homing ability. Hemoglobin acts as an oxygen carrier to relieve the hypoxia and gold nanoparticles work as radiosensitizers to potentiate the sensitivity of tumor cells to X-ray, thus, enhancing the in vivo therapeutic outcome even under a low-dose RT in tumor bearing mice. The enhanced antitumor effect and survival benefits endowed by the Au-Hb@PLT were confirmed in vitro and in vivo. These results demonstrate that these Au-Hb@PLT can work as an oxygen vehicle, offer a promising approach to mitigate hypoxia and improve RT efficacy with a low RT dosage.
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Affiliation(s)
- Donglin Xia
- Institute of Materials Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210093, P. R. China
- School of Public Health, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Daming Hang
- Nantong Tumor Hospital, Nantong, Jiangsu 226362, P.R. China
| | - Yuanyuan Li
- School of Public Health, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Wei Jiang
- Institute of Materials Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210093, P. R. China
| | - Jianfeng Zhu
- Institute of Materials Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210093, P. R. China
| | - Yin Ding
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, P. R. China
| | - Haiying Gu
- School of Public Health, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Yong Hu
- Institute of Materials Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210093, P. R. China
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10
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Rusheen AE, Gee TA, Jang DP, Blaha CD, Bennet KE, Lee KH, Heien ML, Oh Y. Evaluation of electrochemical methods for tonic dopamine detection in vivo. Trends Analyt Chem 2020; 132:116049. [PMID: 33597790 PMCID: PMC7885180 DOI: 10.1016/j.trac.2020.116049] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Dysfunction in dopaminergic neuronal systems underlie a number of neurologic and psychiatric disorders such as Parkinson's disease, drug addiction, and schizophrenia. Dopamine systems communicate via two mechanisms, a fast "phasic" release (sub-second to second) that is related to salient stimuli and a slower "tonic" release (minutes to hours) that regulates receptor tone. Alterations in tonic levels are thought to be more critically important in enabling normal motor, cognitive, and motivational functions, and dysregulation in tonic dopamine levels are associated with neuropsychiatric disorders. Therefore, development of neurochemical recording techniques that enable rapid, selective, and quantitative measurements of changes in tonic extracellular levels are essential in determining the role of dopamine in both normal and disease states. Here, we review state-of-the-art advanced analytical techniques for in vivo detection of tonic levels, with special focus on electrochemical techniques for detection in humans.
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Affiliation(s)
- Aaron E. Rusheen
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, 55905, United States
- Medical Scientist Training Program, Mayo Clinic, Rochester, MN, 55905, United States
| | - Taylor A. Gee
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721, United States
| | - Dong P. Jang
- Department of Biomedical Engineering, Hanyang University, Seoul, 04763, Republic of Korea
| | - Charles D. Blaha
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, 55905, United States
| | - Kevin E. Bennet
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, 55905, United States
- Division of Engineering, Mayo Clinic, Rochester, MN, 55905, United States
| | - Kendall H. Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, 55905, United States
- Department of Biomedical Engineering, Mayo Clinic, Rochester, MN, 55905, United States
| | - Michael L. Heien
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721, United States
| | - Yoonbae Oh
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, 55905, United States
- Department of Biomedical Engineering, Mayo Clinic, Rochester, MN, 55905, United States
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11
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Nano-engineering the material structure of preferentially oriented nano-graphitic carbon for making high-performance electrochemical micro-sensors. Sci Rep 2020; 10:9444. [PMID: 32523076 PMCID: PMC7286892 DOI: 10.1038/s41598-020-66408-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/11/2020] [Indexed: 12/28/2022] Open
Abstract
Direct synthesis of thin-film carbon nanomaterials on oxide-coated silicon substrates provides a viable pathway for building a dense array of miniaturized (micron-scale) electrochemical sensors with high performance. However, material synthesis generally involves many parameters, making material engineering based on trial and error highly inefficient. Here, we report a two-pronged strategy for producing engineered thin-film carbon nanomaterials that have a nano-graphitic structure. First, we introduce a variant of the metal-induced graphitization technique that generates micron-scale islands of nano-graphitic carbon materials directly on oxide-coated silicon substrates. A novel feature of our material synthesis is that, through substrate engineering, the orientation of graphitic planes within the film aligns preferentially with the silicon substrate. This feature allows us to use the Raman spectroscopy for quantifying structural properties of the sensor surface, where the electrochemical processes occur. Second, we find phenomenological models for predicting the amplitudes of the redox current and the sensor capacitance from the material structure, quantified by Raman. Our results indicate that the key to achieving high-performance micro-sensors from nano-graphitic carbon is to increase both the density of point defects and the size of the graphitic crystallites. Our study offers a viable strategy for building planar electrochemical micro-sensors with high-performance.
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12
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Pagan-Diaz GJ, Ramos-Cruz KP, Sam R, Kandel ME, Aydin O, Saif MTA, Popescu G, Bashir R. Engineering geometrical 3-dimensional untethered in vitro neural tissue mimic. Proc Natl Acad Sci U S A 2019; 116:25932-25940. [PMID: 31796592 PMCID: PMC6926042 DOI: 10.1073/pnas.1916138116] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Formation of tissue models in 3 dimensions is more effective in recapitulating structure and function compared to their 2-dimensional (2D) counterparts. Formation of 3D engineered tissue to control shape and size can have important implications in biomedical research and in engineering applications such as biological soft robotics. While neural spheroids routinely are created during differentiation processes, further geometric control of in vitro neural models has not been demonstrated. Here, we present an approach to form functional in vitro neural tissue mimic (NTM) of different shapes using stem cells, a fibrin matrix, and 3D printed molds. We used murine-derived embryonic stem cells for optimizing cell-seeding protocols, characterization of the resulting internal structure of the construct, and remodeling of the extracellular matrix, as well as validation of electrophysiological activity. Then, we used these findings to biofabricate these constructs using neurons derived from human embryonic stem cells. This method can provide a large degree of design flexibility for development of in vitro functional neural tissue models of varying forms for therapeutic biomedical research, drug discovery, and disease modeling, and engineering applications.
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Affiliation(s)
- Gelson J Pagan-Diaz
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Karla P Ramos-Cruz
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Richard Sam
- School of Molecular and Cellular Biology, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Mikhail E Kandel
- Department of Electrical and Computer Engineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Onur Aydin
- Department of Mechanical Science and Engineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - M Taher A Saif
- Department of Mechanical Science and Engineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Gabriel Popescu
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
- Department of Electrical and Computer Engineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Rashid Bashir
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801;
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13
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Liu X, Feng T, Ji W, Wang Z, Zhang M. A cobalt corrole/carbon nanotube enables simultaneous electrochemical monitoring of oxygen and ascorbic acid in the rat brain. Analyst 2019; 145:70-75. [PMID: 31720591 DOI: 10.1039/c9an01946d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is of interest to in vivo monitor the co-dynamics of different substances. However, the tracking of multiple species is still challenging. In this work, we demonstrate an in vivo electrochemical method by using multi-potential step amperometry to in vivo detect ascorbic acid (AA) and oxygen (O2) simultaneously. In order to achieve good selectivity and high sensitivity for both AA and O2, we design a cobalt corrole [Co(tpfc)(py)2] (tpfc = 5,10,15-tris(penta-fluorophenyl) corrole, py = pyridine, denoted as Co-TPFC) and carbon nanotube nanocomposite to modify a carbon fiber microelectrode (Co-TPFC/MWNT/CFE). This Co-TPFC/MWNT/CFE exhibits excellent electrocatalytic properties towards the reduction of O2 preceding a 4e process and facilitates the oxidation of AA at low potential in the physiological environment. Based on this, we realize simultaneous detection of AA and O2 using two-potential steps (one cathodic (-0.2 V) and the other anodic (+0.05 V)) with 1 second step time. Both in vitro and in vivo experiments proved the feasibility of this method. This demonstrated strategy is useful for us to understand various physiological and pathological processes associated with O2 and AA co-dynamics, and also provides an idea for detecting multiple substances simultaneously.
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Affiliation(s)
- Xiaomeng Liu
- Department of Chemistry, Renmin University of China, Beijing 100872, China.
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14
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Yang F, Liu P, Hao T, Wu Y, Ma S, Hu Y, Wang S, Guo Z. Fast-Scan Anodic Stripping Voltammetry for Detection of Pb(II) at Picomolar Level. RUSS J ELECTROCHEM+ 2019. [DOI: 10.1134/s1023193519020162] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Wu T, Alharbi A, Kiani R, Shahrjerdi D. Quantitative Principles for Precise Engineering of Sensitivity in Graphene Electrochemical Sensors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1805752. [PMID: 30548684 PMCID: PMC6823930 DOI: 10.1002/adma.201805752] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/11/2018] [Indexed: 05/15/2023]
Abstract
A major difficulty in implementing carbon-based electrode arrays with high device-packing density is to ensure homogeneous and high sensitivities across the array. Overcoming this obstacle requires quantitative microscopic models that can accurately predict electrode sensitivity from its material structure. Such models are currently lacking. Here, it is shown that the sensitivity of graphene electrodes to dopamine and serotonin neurochemicals in fast-scan cyclic voltammetry measurements is strongly linked to point defects, whereas it is unaffected by line defects. Using the physics of point defects in graphene, a microscopic model is introduced that explains how point defects determine sensitivity. The predictions of this model match the empirical observation that sensitivity linearly increases with the density of point defects. This model is used to guide the nanoengineering of graphene structures for optimum sensitivity. This approach achieves reproducible fabrication of miniaturized sensors with extraordinarily higher sensitivity than conventional materials. These results lay the foundation for new integrated electrochemical sensor arrays based on nanoengineered graphene.
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Affiliation(s)
- Ting Wu
- Electrical and Computer Engineering, New York University, Brooklyn, NY, 11201, USA
| | - Abdullah Alharbi
- Electrical and Computer Engineering, New York University, Brooklyn, NY, 11201, USA
| | - Roozbeh Kiani
- Center for Neural Science, New York University, New York, NY, 10003, USA
- Neuroscience Institute, New York University Langone Medical Center, New York, NY, 10016, USA
| | - Davood Shahrjerdi
- Electrical and Computer Engineering, New York University, Brooklyn, NY, 11201, USA
- Center for Quantum Phenomena, Physics Department, New York University, New York, NY, 10003, USA
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16
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Cao Q, Puthongkham P, Venton BJ. Review: New insights into optimizing chemical and 3D surface structures of carbon electrodes for neurotransmitter detection. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2019; 11:247-261. [PMID: 30740148 PMCID: PMC6366673 DOI: 10.1039/c8ay02472c] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The carbon-fiber microelectrode has been used for decades as a neurotransmitter sensor. Recently, new strategies have been developed for making carbon electrodes, including using carbon nanomaterials or pyrolyzing photoresist etched by nanolithography or 3D printing. This review summarizes how chemical and 3D surface structures of new carbon electrodes are optimized for neurotransmitter detection. There are effects of the chemical structure that are advantageous and nanomaterials are used ranging from carbon nanotube (CNT) to graphene to nanodiamond. Functionalization of these materials promotes surface oxide groups that adsorb dopamine and dopants introduce defect sites good for electron transfer. Polymer coatings such as poly(3,4-ethylenedioxythiophene) (PEDOT) or Nafion also enhance the selectivity, particularly for dopamine over ascorbic acid. Changing the 3D surface structure of an electrode increases current by adding more surface area. If the surface structure has roughness or pores on the micron scale, the electrode also acts as a thin layer cell, momentarily trapping the analyte for redox cycling. Vertically-aligned CNTs as well as lithographically-made or 3D printed pillar arrays act as thin layer cells, producing more reversible cyclic voltammograms. A better understanding of how chemical and surface structure affects electrochemistry enables rational design of electrodes. New carbon electrodes are being tested in vivo and strategies to reduce biofouling are being developed. Future studies should test the robustness for long term implantation, explore electrochemical properties of neurotransmitters beyond dopamine, and combine optimized chemical and physical structures for real-time monitoring of neurotransmitters.
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Affiliation(s)
| | | | - B. Jill Venton
- Dept. of Chemistry, University of Virginia, Charlottesville, VA 22901
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17
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Baig N, Rana A, Kawde AN. Modified Electrodes for Selective Voltammetric Detection of Biomolecules. ELECTROANAL 2018. [DOI: 10.1002/elan.201800468] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Nadeem Baig
- Chemistry Department, College of Sciences; King Fahd University of Petroleum and Minerals; Dhahran 31261 Saudi Arabia
| | - Azeem Rana
- Chemistry Department, College of Sciences; King Fahd University of Petroleum and Minerals; Dhahran 31261 Saudi Arabia
| | - Abdel-Nasser Kawde
- Chemistry Department, College of Sciences; King Fahd University of Petroleum and Minerals; Dhahran 31261 Saudi Arabia
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18
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Dorta-Quiñones CI, Huang M, Ruelas JC, Delacruz J, Apsel AB, Minch BA, Lindau M. A Bidirectional-Current CMOS Potentiostat for Fast-Scan Cyclic Voltammetry Detector Arrays. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2018; 12:894-903. [PMID: 29994774 PMCID: PMC6131114 DOI: 10.1109/tbcas.2018.2828828] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A potentiostat circuit for the application of bipolar electrode voltages and detection of bidirectional currents using a microelectrode array is presented. The potentiostat operates as a regulated-cascode amplifier for positive input currents, and as an active-input regulated-cascode mirror for negative input currents. This topology enables constant-potential amperometry and fast-scan cyclic voltammetry (FSCV) at microelectrode arrays for parallel recording of quantal release events, electrode impedance characterization, and high-throughput drug screening. A 64-channel FSCV detector array, fabricated in a 0.5-$\mu$m, 5-V CMOS process, is also demonstrated. Each detector occupies an area of 45 $\mu$m $\times$ 30 $\mu$m and consists of only 14 transistors and a 50-fF integrating capacitor. The system was validated using prerecorded input stimuli from actual FSCV measurements at a carbon-fiber microelectrode.
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Affiliation(s)
| | - Meng Huang
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853 USA ()
| | - John C. Ruelas
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853 USA ()
| | - Joannalyn Delacruz
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853 USA ()
| | - Alyssa B. Apsel
- School of Electrical and Computer Engineering,Cornell University, Ithaca, NY 14853 USA ()
| | - Bradley A. Minch
- Franklin W. Olin College of Engineering, Needham,MA 02492 USA ()
| | - Manfred Lindau
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853 USA ()
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19
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Sugime H, Ushiyama T, Nishimura K, Ohno Y, Noda S. An interdigitated electrode with dense carbon nanotube forests on conductive supports for electrochemical biosensors. Analyst 2018; 143:3635-3642. [PMID: 29956699 DOI: 10.1039/c8an00528a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A highly sensitive interdigitated electrode (IDE) with vertically aligned dense carbon nanotube forests directly grown on conductive supports was demonstrated by combining UV lithography and a low temperature chemical vapor deposition process (470 °C). The cyclic voltammetry (CV) measurements of K4[Fe(CN)6] showed that the redox current of the IDE with CNT forests (CNTF-IDE) reached the steady state much more quickly compared to that of conventional gold IDE (Au-IDE). The performance of the CNTF-IDE largely depended on the geometry of the electrodes (e.g. width and gap). With the optimum three-dimensional electrode structure, the anodic current was amplified by a factor of ∼18 and ∼67 in the CV and the chronoamperometry measurements, respectively. The collection efficiency, defined as the ratio of the cathodic current to the anodic current at steady state, was improved up to 97.3%. The selective detection of dopamine (DA) under the coexistence of l-ascorbic acid with high concentration (100 μM) was achieved with a linear range of 100 nM-100 μM, a sensitivity of 14.3 mA mol-1 L, and a limit of detection (LOD, S/N = 3) of 42 nM. Compared to the conventional carbon electrodes, the CNTF-IDE showed superior anti-fouling property, which is of significant importance for practical applications, with a negligible shift of the half-wave potential (ΔE1/2 < 1.4 mV) for repeated CV measurements of DA at high concentration (100 μM).
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Affiliation(s)
- Hisashi Sugime
- Waseda Institute for Advanced Study, Waseda University, 1-6-1 Nishi Waseda, Shijuku-ku, Tokyo 169-8050, Japan.
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20
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Ngernsutivorakul T, White TS, Kennedy RT. Microfabricated Probes for Studying Brain Chemistry: A Review. Chemphyschem 2018; 19:1128-1142. [PMID: 29405568 PMCID: PMC6996029 DOI: 10.1002/cphc.201701180] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Indexed: 12/13/2022]
Abstract
Probe techniques for monitoring in vivo chemistry (e.g., electrochemical sensors and microdialysis sampling probes) have significantly contributed to a better understanding of neurotransmission in correlation to behaviors and neurological disorders. Microfabrication allows construction of neural probes with high reproducibility, scalability, design flexibility, and multiplexed features. This technology has translated well into fabricating miniaturized neurochemical probes for electrochemical detection and sampling. Microfabricated electrochemical probes provide a better control of spatial resolution with multisite detection on a single compact platform. This development allows the observation of heterogeneity of neurochemical activity precisely within the brain region. Microfabricated sampling probes are starting to emerge that enable chemical measurements at high spatial resolution and potential for reducing tissue damage. Recent advancement in analytical methods also facilitates neurochemical monitoring at high temporal resolution. Furthermore, a positive feature of microfabricated probes is that they can be feasibly built with other sensing and stimulating platforms including optogenetics. Such integrated probes will empower researchers to precisely elucidate brain function and develop novel treatments for neurological disorders.
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Affiliation(s)
| | - Thomas S. White
- Macromolecular Science and Engineering, University of Michigan, 3003E, NCRC Building 28, 2800 Plymouth Rd., Ann Arbor, MI 48109
| | - Robert T. Kennedy
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan, 1150 W. Medical Center Drive, Ann Arbor, MI 48109
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21
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Nimbalkar S, Castagnola E, Balasubramani A, Scarpellini A, Samejima S, Khorasani A, Boissenin A, Thongpang S, Moritz C, Kassegne S. Ultra-Capacitive Carbon Neural Probe Allows Simultaneous Long-Term Electrical Stimulations and High-Resolution Neurotransmitter Detection. Sci Rep 2018; 8:6958. [PMID: 29725133 PMCID: PMC5934383 DOI: 10.1038/s41598-018-25198-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 04/16/2018] [Indexed: 11/09/2022] Open
Abstract
We present a new class of carbon-based neural probes that consist of homogeneous glassy carbon (GC) microelectrodes, interconnects and bump pads. These electrodes have purely capacitive behavior with exceptionally high charge storage capacity (CSC) and are capable of sustaining more than 3.5 billion cycles of bi-phasic pulses at charge density of 0.25 mC/cm2. These probes enable both high SNR (>16) electrical signal recording and remarkably high-resolution real-time neurotransmitter detection, on the same platform. Leveraging a new 2-step, double-sided pattern transfer method for GC structures, these probes allow extended long-term electrical stimulation with no electrode material corrosion. Cross-section characterization through FIB and SEM imaging demonstrate strong attachment enabled by hydroxyl and carbonyl covalent bonds between GC microstructures and top insulating and bottom substrate layers. Extensive in-vivo and in-vitro tests confirmed: (i) high SNR (>16) recordings, (ii) highest reported CSC for non-coated neural probe (61.4 ± 6.9 mC/cm2), (iii) high-resolution dopamine detection (10 nM level - one of the lowest reported so far), (iv) recording of both electrical and electrochemical signals, and (v) no failure after 3.5 billion cycles of pulses. Therefore, these probes offer a compelling multi-modal platform for long-term applications of neural probe technology in both experimental and clinical neuroscience.
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Affiliation(s)
- Surabhi Nimbalkar
- MEMS Research Lab, Department of Mechanical Engineering College of Engineering, 5500 Campanile Drive, San Diego State University, San Diego, CA, 92182, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Elisa Castagnola
- MEMS Research Lab, Department of Mechanical Engineering College of Engineering, 5500 Campanile Drive, San Diego State University, San Diego, CA, 92182, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Arvind Balasubramani
- MEMS Research Lab, Department of Mechanical Engineering College of Engineering, 5500 Campanile Drive, San Diego State University, San Diego, CA, 92182, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Alice Scarpellini
- Department of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genoa, Italy
| | - Soshi Samejima
- University of Washington, Division of Physical Therapy Departments of Rehabilitation Medicine and Physiology and Biophysics, Seattle, WA, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Abed Khorasani
- University of Washington, Division of Physical Therapy Departments of Rehabilitation Medicine and Physiology and Biophysics, Seattle, WA, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Adrien Boissenin
- University of Washington, Division of Physical Therapy Departments of Rehabilitation Medicine and Physiology and Biophysics, Seattle, WA, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Sanitta Thongpang
- University of Washington, Division of Physical Therapy Departments of Rehabilitation Medicine and Physiology and Biophysics, Seattle, WA, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Chet Moritz
- University of Washington, Division of Physical Therapy Departments of Rehabilitation Medicine and Physiology and Biophysics, Seattle, WA, USA.,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA
| | - Sam Kassegne
- MEMS Research Lab, Department of Mechanical Engineering College of Engineering, 5500 Campanile Drive, San Diego State University, San Diego, CA, 92182, USA. .,NSF-ERC Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, USA.
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22
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Demuru S, Nela L, Marchack N, Holmes SJ, Farmer DB, Tulevski GS, Lin Q, Deligianni H. Scalable Nanostructured Carbon Electrode Arrays for Enhanced Dopamine Detection. ACS Sens 2018; 3:799-805. [PMID: 29480715 DOI: 10.1021/acssensors.8b00043] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Dopamine is a neurotransmitter that modulates arousal and motivation in humans and animals. It plays a central role in the brain "reward" system. Its dysregulation is involved in several debilitating disorders such as addiction, depression, Parkinson's disease, and schizophrenia. Dopamine neurotransmission and its reuptake in extracellular space takes place with millisecond temporal and nanometer spatial resolution. Novel nanoscale electrodes are needed with superior sensitivity and improved spatial resolution to gain an improved understanding of dopamine dysregulation. We report on a scalable fabrication of dopamine neurochemical probes of a nanostructured glassy carbon that is smaller than any existing dopamine sensor and arrays of more than 6000 nanorod probes. We also report on the electrochemical dopamine sensing of the glassy carbon nanorod electrode. Compared with a carbon fiber, the nanostructured glassy carbon nanorods provide about 2× higher sensitivity per unit area for dopamine sensing and more than 5× higher signal per unit area at low concentration of dopamine, with comparable LOD and time response. These glassy carbon nanorods were fabricated by pyrolysis of a lithographically defined polymeric nanostructure with an industry standard semiconductor fabrication infrastructure. The scalable fabrication strategy offers the potential to integrate these nanoscale carbon rods with an integrated circuit control system and with other complementary metal oxide semiconductor (CMOS) compatible sensors.
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Affiliation(s)
| | | | - Nathan Marchack
- IBM, Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States
| | - Steven J. Holmes
- IBM, Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States
| | - Damon B. Farmer
- IBM, Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States
| | - George S. Tulevski
- IBM, Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States
| | - Qinghuang Lin
- IBM, Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States
| | - Hariklia Deligianni
- IBM, Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States
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23
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Tan C, Dutta G, Yin H, Siddiqui S, Arumugam PU. Detection of neurochemicals with enhanced sensitivity and selectivity via hybrid multiwall carbon nanotube-ultrananocrystalline diamond microelectrodes. SENSORS AND ACTUATORS. B, CHEMICAL 2018; 258:193-203. [PMID: 32528220 PMCID: PMC7289503 DOI: 10.1016/j.snb.2017.11.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Abnormal neurochemical signaling is often the underlying cause of brain disorders. Electrochemical microsensors are widely used to monitor neurochemicals with high spatial-temporal resolution. However, they rely on carbon fiber microelectrodes that often limit their sensing performance. In this study, we demonstrate the potential of a hybrid multiwall carbon nanotube (MWCNT) film modified boron-doped ultrananocrystalline diamond (UNCD) microelectrode (250 μm diameter) microsensor for improved detection of dopamine (DA) in the presence of common interferents. A series of modified microelectrodes with varying film thicknesses were microfabricated by electrophoretic deposition (EPD) and characterized by scanning electron microscopy, x-ray photoelectron spectroscopy, electrochemical impedance spectroscopy (EIS) and silver deposition imaging. Using cyclic voltammetry, the 100-nm "thin" film microelectrode produced the most favorable combination of DA sensitivity value of 36 ±2% μA/μM/cm2 with a linear range of 33 nM to 1 μM and a limit of detection (LOD) of 9.5 ± 1.2% nM. The EIS spectra of these microelectrodes revealed three regions with inhomogeneous pore geometry and differing impedance values and electrochemical activity, which was found to be film thickness dependent. Using differential pulse voltammetry, the modified microelectrode showed excellent selectivity by exhibiting three distinct peaks for the DA, serotonin and excess ascorbic acid in a ternary mixture. These results provide two key benefits: first, remarkable improvements in DA sensitivity (>125-fold), selectivity (>2000-fold) and LOD (>180-fold), second, these MWCNTs can be selectively coated with a simple, scalable and low cost EPD process for highly multiplexed microsensor technologies. These advances offer considerable promise for further progress in chemical neurosciences.
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24
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Wellman SM, Eles JR, Ludwig KA, Seymour JP, Michelson NJ, McFadden WE, Vazquez AL, Kozai TDY. A Materials Roadmap to Functional Neural Interface Design. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1701269. [PMID: 29805350 PMCID: PMC5963731 DOI: 10.1002/adfm.201701269] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Advancement in neurotechnologies for electrophysiology, neurochemical sensing, neuromodulation, and optogenetics are revolutionizing scientific understanding of the brain while enabling treatments, cures, and preventative measures for a variety of neurological disorders. The grand challenge in neural interface engineering is to seamlessly integrate the interface between neurobiology and engineered technology, to record from and modulate neurons over chronic timescales. However, the biological inflammatory response to implants, neural degeneration, and long-term material stability diminish the quality of interface overtime. Recent advances in functional materials have been aimed at engineering solutions for chronic neural interfaces. Yet, the development and deployment of neural interfaces designed from novel materials have introduced new challenges that have largely avoided being addressed. Many engineering efforts that solely focus on optimizing individual probe design parameters, such as softness or flexibility, downplay critical multi-dimensional interactions between different physical properties of the device that contribute to overall performance and biocompatibility. Moreover, the use of these new materials present substantial new difficulties that must be addressed before regulatory approval for use in human patients will be achievable. In this review, the interdependence of different electrode components are highlighted to demonstrate the current materials-based challenges facing the field of neural interface engineering.
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Affiliation(s)
- Steven M Wellman
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - James R Eles
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - Kip A Ludwig
- Department of Neurologic Surgery, 200 First St. SW, Rochester, MN 55905
| | - John P Seymour
- Electrical & Computer Engineering, 1301 Beal Ave., 2227 EECS, Ann Arbor, MI 48109
| | - Nicholas J Michelson
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - William E McFadden
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - Alberto L Vazquez
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - Takashi D Y Kozai
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
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25
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Castagnola E, Vahidi NW, Nimbalkar S, Rudraraju S, Thielk M, Zucchini E, Cea C, Carli S, Gentner TQ, Ricci D, Fadiga L, Kassegne S. In Vivo Dopamine Detection and Single Unit Recordings Using Intracortical Glassy Carbon Microelectrode Arrays. ACTA ACUST UNITED AC 2018; 3:1629-1634. [PMID: 29881642 DOI: 10.1557/adv.2018.98] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In this study, we present a 4-channel intracortical glassy carbon (GC) microelectrode array on a flexible substrate for the simultaneous in vivo neural activity recording and dopamine (DA) concentration measurement at four different brain locations (220μm vertical spacing). The ability of GC microelectrodes to detect DA was firstly assessed in vitro in phosphate-buffered saline solution and then validated in vivo measuring spontaneous DA concentration in the Striatum of European Starling songbird through fast scan cyclic voltammetry (FSCV). The capability of GC microelectrode arrays and commercial penetrating metal microelectrode arrays to record neural activity from the Caudomedial Neostriatum of European starling songbird was compared. Preliminary results demonstrated the ability of GC microelectrodes in detecting neurotransmitters release and recording neural activity in vivo. GC microelectrodes array may, therefore, offer a new opportunity to understand the intimate relations linking electrophysiological parameters with neurotransmitters release.
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Affiliation(s)
- Elisa Castagnola
- MEMS Research Lab., Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-1323, USA.,Center for Sensorimotor Neural Engineering (CSNE), Box 37, 1414 NE 42nd St., Suite 204, Seattle, WA 98105-6271, USA
| | - Nasim Winchester Vahidi
- Dept. of Electrical Engineering, University of California San Diego, La Jolla, CA 92093, USA.,Neurosciences Graduate Program, University of California San Diego, 9500 Gilman Dr, La Jolla, CA, USA
| | - Surabhi Nimbalkar
- MEMS Research Lab., Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-1323, USA.,Center for Sensorimotor Neural Engineering (CSNE), Box 37, 1414 NE 42nd St., Suite 204, Seattle, WA 98105-6271, USA
| | - Srihita Rudraraju
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Marvin Thielk
- Neurosciences Graduate Program, University of California San Diego, 9500 Gilman Dr, La Jolla, CA, USA
| | - Elena Zucchini
- Center for Translational Neurophysiology of Speech and Communication, Istituto Italiano di Tecnologia, Via Fossato di Mortara 17/19, 44121, Ferrara, Italy
| | - Claudia Cea
- MEMS Research Lab., Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-1323, USA.,Center for Sensorimotor Neural Engineering (CSNE), Box 37, 1414 NE 42nd St., Suite 204, Seattle, WA 98105-6271, USA
| | - Stefano Carli
- Center for Translational Neurophysiology of Speech and Communication, Istituto Italiano di Tecnologia, Via Fossato di Mortara 17/19, 44121, Ferrara, Italy
| | - Timothy Q Gentner
- Neurosciences Graduate Program, University of California San Diego, 9500 Gilman Dr, La Jolla, CA, USA
| | - Davide Ricci
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Luciano Fadiga
- Center for Translational Neurophysiology of Speech and Communication, Istituto Italiano di Tecnologia, Via Fossato di Mortara 17/19, 44121, Ferrara, Italy.,Human Physiology, University of Ferrara, Via Fossato di Mortara 17/19, 44121, Ferrara, Italy
| | - Sam Kassegne
- MEMS Research Lab., Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-1323, USA.,Center for Sensorimotor Neural Engineering (CSNE), Box 37, 1414 NE 42nd St., Suite 204, Seattle, WA 98105-6271, USA
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26
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Beyene AG, McFarlane IR, Pinals RL, Landry MP. Stochastic Simulation of Dopamine Neuromodulation for Implementation of Fluorescent Neurochemical Probes in the Striatal Extracellular Space. ACS Chem Neurosci 2017; 8:2275-2289. [PMID: 28714693 PMCID: PMC10494912 DOI: 10.1021/acschemneuro.7b00193] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Imaging the dynamic behavior of neuromodulatory neurotransmitters in the extracelluar space that arise from individual quantal release events would constitute a major advance in neurochemical imaging. Spatial and temporal resolution of these highly stochastic neuromodulatory events requires concurrent advances in the chemical development of optical nanosensors selective for neuromodulators in concert with advances in imaging methodologies to capture millisecond neurotransmitter release. Herein, we develop and implement a stochastic model to describe dopamine dynamics in the extracellular space (ECS) of the brain dorsal striatum to guide the design and implementation of fluorescent neurochemical probes that record neurotransmitter dynamics in the ECS. Our model is developed from first-principles and simulates release, diffusion, and reuptake of dopamine in a 3D simulation volume of striatal tissue. We find that in vivo imaging of neuromodulation requires simultaneous optimization of dopamine nanosensor reversibility and sensitivity: dopamine imaging in the striatum or nucleus accumbens requires nanosensors with an optimal dopamine dissociation constant (Kd) of 1 μM, whereas Kds above 10 μM are required for dopamine imaging in the prefrontal cortex. Furthermore, as a result of the probabilistic nature of dopamine terminal activity in the striatum, our model reveals that imaging frame rates of 20 Hz are optimal for recording temporally resolved dopamine release events. Our work provides a modeling platform to probe how complex neuromodulatory processes can be studied with fluorescent nanosensors and enables direct evaluation of nanosensor chemistry and imaging hardware parameters. Our stochastic model is generic for evaluating fluorescent neurotransmission probes, and is broadly applicable to the design of other neurotransmitter fluorophores and their optimization for implementation in vivo.
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Affiliation(s)
- Abraham G. Beyene
- Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Ian R. McFarlane
- Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Rebecca L. Pinals
- Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Markita P. Landry
- Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- California Institute for Quantitative Biosciences, QB3, University of California, Berkeley, California 94720, United States
- Chan Zuckerberg Biohub, San Francisco, California 94158, United States
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27
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3D carbon nanofiber microelectrode arrays fabricated by plasma-assisted pyrolysis to enhance sensitivity and stability of real-time dopamine detection. Biomed Microdevices 2017; 18:112. [PMID: 27900618 DOI: 10.1007/s10544-016-0136-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In this paper, we have fabricated 3D carbon nanofiber microelectrode arrays (MEAs) with highly reproducible and rich chemical surface areas for fast scan cyclic voltammetry (FSCV). Carbon nanofibers are created from negative photoresist by a new process called dual O2 plasma-assisted pyrolysis. The proposed approach significantly improves film adhesion and increases surface reactivity. We showcase our sensor's compatibility with FSCV analysis by demonstrating highly sensitive and stable FSCV dopamine measurements on a prototype 4-channel array. We envision with proper surface fuctionalization the 3D carbon nanofiber MEA enable sensitive and reliable detection of multiple neurotransmitters simultaneously.
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28
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Integrated multi-ISE arrays with improved sensitivity, accuracy and precision. Sci Rep 2017; 7:44771. [PMID: 28303939 PMCID: PMC5356001 DOI: 10.1038/srep44771] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 02/13/2017] [Indexed: 01/22/2023] Open
Abstract
Increasing use of ion-selective electrodes (ISEs) in the biological and environmental fields has generated demand for high-sensitivity ISEs. However, improving the sensitivities of ISEs remains a challenge because of the limit of the Nernstian slope (59.2/n mV). Here, we present a universal ion detection method using an electronic integrated multi-electrode system (EIMES) that bypasses the Nernstian slope limit of 59.2/n mV, thereby enabling substantial enhancement of the sensitivity of ISEs. The results reveal that the response slope is greatly increased from 57.2 to 1711.3 mV, 57.3 to 564.7 mV and 57.7 to 576.2 mV by electronic integrated 30 Cl− electrodes, 10 F− electrodes and 10 glass pH electrodes, respectively. Thus, a tiny change in the ion concentration can be monitored, and correspondingly, the accuracy and precision are substantially improved. The EIMES is suited for all types of potentiometric sensors and may pave the way for monitoring of various ions with high accuracy and precision because of its high sensitivity.
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29
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Cortés M, Smida H, Mériadec C, Barrière F, Lagrost C. Direct SN1 reaction at oxidized PPF surfaces. Electrochem commun 2017. [DOI: 10.1016/j.elecom.2016.12.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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30
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Peltola E, Heikkinen JJ, Sovanto K, Sainio S, Aarva A, Franssila S, Jokinen V, Laurila T. SU-8 based pyrolytic carbon for the electrochemical detection of dopamine. J Mater Chem B 2017; 5:9033-9044. [DOI: 10.1039/c7tb02469j] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Here we investigated the electrochemical properties and dopamine (DA) detection capability of SU-8 photoresist based pyrolytic carbon (PyC) as well as its biocompatibility with neural cells.
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Affiliation(s)
- Emilia Peltola
- Department of Electrical Engineering and Automation
- School of Electrical Engineering
- Aalto University
- Espoo
- Finland
| | - Joonas J. Heikkinen
- Department of Chemistry and Materials Science
- School of Chemical Engineering
- Aalto University
- Finland
| | - Katariina Sovanto
- Department of Electrical Engineering and Automation
- School of Electrical Engineering
- Aalto University
- Espoo
- Finland
| | - Sami Sainio
- Department of Electrical Engineering and Automation
- School of Electrical Engineering
- Aalto University
- Espoo
- Finland
| | - Anja Aarva
- Department of Electrical Engineering and Automation
- School of Electrical Engineering
- Aalto University
- Espoo
- Finland
| | - Sami Franssila
- Department of Chemistry and Materials Science
- School of Chemical Engineering
- Aalto University
- Finland
| | - Ville Jokinen
- Department of Chemistry and Materials Science
- School of Chemical Engineering
- Aalto University
- Finland
| | - Tomi Laurila
- Department of Electrical Engineering and Automation
- School of Electrical Engineering
- Aalto University
- Espoo
- Finland
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31
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Xiao T, Wu F, Hao J, Zhang M, Yu P, Mao L. In Vivo Analysis with Electrochemical Sensors and Biosensors. Anal Chem 2016; 89:300-313. [DOI: 10.1021/acs.analchem.6b04308] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Tongfang Xiao
- Beijing
National Laboratory for Molecular Sciences, CAS Key Laboratory of
Analytical Chemistry for Living Biosystems and Photochemistry, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fei Wu
- Beijing
National Laboratory for Molecular Sciences, CAS Key Laboratory of
Analytical Chemistry for Living Biosystems and Photochemistry, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Hao
- Beijing
National Laboratory for Molecular Sciences, CAS Key Laboratory of
Analytical Chemistry for Living Biosystems and Photochemistry, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Meining Zhang
- Beijing
National Laboratory for Molecular Sciences, CAS Key Laboratory of
Analytical Chemistry for Living Biosystems and Photochemistry, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Yu
- Beijing
National Laboratory for Molecular Sciences, CAS Key Laboratory of
Analytical Chemistry for Living Biosystems and Photochemistry, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lanqun Mao
- Beijing
National Laboratory for Molecular Sciences, CAS Key Laboratory of
Analytical Chemistry for Living Biosystems and Photochemistry, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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32
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Zhang W, Zhu S, Luque R, Han S, Hu L, Xu G. Recent development of carbon electrode materials and their bioanalytical and environmental applications. Chem Soc Rev 2016; 45:715-52. [DOI: 10.1039/c5cs00297d] [Citation(s) in RCA: 210] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
New synthetic approaches, materials, properties, electroanalytical applications and perspectives of carbon materials are presented.
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Affiliation(s)
- Wei Zhang
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- China
| | - Shuyun Zhu
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- China
| | - Rafael Luque
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- China
| | - Shuang Han
- Shenyang University of Chemical Technology
- Shenyang
- China
| | - Lianzhe Hu
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- China
| | - Guobao Xu
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- China
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33
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Dengler AK, Wightman RM, McCarty GS. Microfabricated Collector-Generator Electrode Sensor for Measuring Absolute pH and Oxygen Concentrations. Anal Chem 2015; 87:10556-64. [PMID: 26375039 DOI: 10.1021/acs.analchem.5b02866] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Fast-scan cyclic voltammetry (FSCV) has attracted attention for studying in vivo neurotransmission due to its subsecond temporal resolution, selectivity, and sensitivity. Traditional FSCV measurements use background subtraction to isolate changes in the local electrochemical environment, providing detailed information on fluctuations in the concentration of electroactive species. This background subtraction removes information about constant or slowly changing concentrations. However, determination of background concentrations is still important for understanding functioning brain tissue. For example, neural activity is known to consume oxygen and produce carbon dioxide which affects local levels of oxygen and pH. Here, we present a microfabricated microelectrode array which uses FSCV to detect the absolute levels of oxygen and pH in vitro. The sensor is a collector-generator electrode array with carbon microelectrodes spaced 5 μm apart. In this work, a periodic potential step is applied at the generator producing transient local changes in the electrochemical environment. The collector electrode continuously performs FSCV enabling these induced changes in concentration to be recorded with the sensitivity and selectivity of FSCV. A negative potential step applied at the generator produces a transient local pH shift at the collector. The generator-induced pH signal is detected using FSCV at the collector and correlated to absolute solution pH by postcalibration of the anodic peak position. In addition, in oxygenated solutions a negative potential step at the generator produces hydrogen peroxide by reducing oxygen. Hydrogen peroxide is detected with FSCV at the collector electrode, and the magnitude of the oxidative peak is proportional to absolute oxygen concentrations. Oxygen interference on the pH signal is minimal and can be accounted for with a postcalibration.
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Affiliation(s)
- Adam K Dengler
- Department of Biomedical Engineering, North Carolina State University , Raleigh, North Carolina 27695, United States
| | - R Mark Wightman
- Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States
| | - Gregory S McCarty
- Department of Biomedical Engineering, North Carolina State University , Raleigh, North Carolina 27695, United States
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34
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Pyrolyzed Photoresist Carbon Electrodes for Trace Electroanalysis of Nickel(II). CHEMOSENSORS 2015. [DOI: 10.3390/chemosensors3020157] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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35
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Abstract
Carbon nanoelectrodes with tip diameters ranging from tens to hundreds of nanometers are fabricated by pyrolitic deposition of carbon films along the entire inner surfaces of pulled-glass pipettes. The pulled end of each glass pipette is then etched to expose a desired length (typically, a few micrometers) of carbon pipe. The carbon film provides an electrically conductive path from the nanoscopic carbon tip to the distal, macroscopic end of the pipette, bridging between the nanoscale tip and the macroscale handle, without a need for assembly. We used our nanoelectrodes to penetrate into individual cells and cell nuclei and measured the variations in the electrode impedance upon cell and nucleus penetration as well as the electrode impedance as a function of cell penetration depth. Theoretical predictions based on a simple circuit model were in good agreement with experimental data.
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Affiliation(s)
- Sean E. Anderson
- University of Pennsylvania, Department of Mechanical Engineering and Applied Mechanics, Philadelphia, PA 19104
| | - Haim H. Bau
- University of Pennsylvania, Department of Mechanical Engineering and Applied Mechanics, Philadelphia, PA 19104
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36
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A Highly Sensitive and Selective Multiwall Carbon Nanotubes/Nafion/Au Microarrays Electrode for Dopamine Determination. ELECTROANAL 2014. [DOI: 10.1002/elan.201400133] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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37
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Patel BA, Luk CC, Leow PL, Lee AJ, Zaidi W, Syed NI. A planar microelectrode array for simultaneous detection of electrically evoked dopamine release from distinct locations of a single isolated neuron. Analyst 2013; 138:2833-9. [PMID: 23462822 DOI: 10.1039/c3an36770c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neurotransmission is a key process of communication between neurons. Although much is known about this process and the influence it has on the function of the body, little is understood about the dynamics of signalling from structural regions of a single neuron. In this study we have fabricated and characterised a microelectrode array (MEA) which was utilised for simultaneous multi-site recordings of dopamine release from an isolated single neuron. The MEA consisted of gold electrodes that were created in plane with the insulation layer using a chemical mechanical planarization process. The detection limit for dopamine measurements was 11 ± 3 nM and all the gold electrodes performed in a consistent fashion during amperometric recordings of 100 nM dopamine. Fouling of the gold electrode was investigated, where no significant change in the current was observed over 4 hours when monitoring 100 nM dopamine. The MEA was accessed using freshly isolated dopaminergic somas from the pond snail, Lymnaea stagnalis, where electrically evoked dopamine release was clearly observed. Measurements were conducted at four structural locations of a single isolated neuron, where electrically evoked dopamine release was observed from the cell body, axonal regions and the terminal. Over time, the release of dopamine varied over the structural regions of the neuron. Such information can provide an insight into the signalling mechanism of neurons and how they potentially form synaptic connections.
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Affiliation(s)
- Bhavik Anil Patel
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, East Sussex, UK.
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38
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Bucher ES, Brooks K, Verber MD, Keithley RB, Owesson-White C, Carroll S, Takmakov P, McKinney CJ, Wightman RM. Flexible software platform for fast-scan cyclic voltammetry data acquisition and analysis. Anal Chem 2013; 85:10344-53. [PMID: 24083898 PMCID: PMC3838858 DOI: 10.1021/ac402263x] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Over the last several decades, fast-scan cyclic voltammetry (FSCV) has proved to be a valuable analytical tool for the real-time measurement of neurotransmitter dynamics in vitro and in vivo. Indeed, FSCV has found application in a wide variety of disciplines including electrochemistry, neurobiology, and behavioral psychology. The maturation of FSCV as an in vivo technique led users to pose increasingly complex questions that require a more sophisticated experimental design. To accommodate recent and future advances in FSCV application, our lab has developed High Definition Cyclic Voltammetry (HDCV). HDCV is an electrochemical software suite that includes data acquisition and analysis programs. The data collection program delivers greater experimental flexibility and better user feedback through live displays. It supports experiments involving multiple electrodes with customized waveforms. It is compatible with transistor-transistor logic-based systems that are used for monitoring animal behavior, and it enables simultaneous recording of electrochemical and electrophysiological data. HDCV analysis streamlines data processing with superior filtering options, seamlessly manages behavioral events, and integrates chemometric processing. Furthermore, analysis is capable of handling single files collected over extended periods of time, allowing the user to consider biological events on both subsecond and multiminute time scales. Here we describe and demonstrate the utility of HDCV for in vivo experiments.
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Affiliation(s)
- Elizabeth S. Bucher
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | - Kenneth Brooks
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | - Matthew D. Verber
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | | | - Catarina Owesson-White
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | - Susan Carroll
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | - Pavel Takmakov
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | - Collin J. McKinney
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
| | - R. Mark Wightman
- Department of Chemistry and Neuroscience Center University of North Carolina at Chapel Hill Chapel Hill, NC 27599-3290
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39
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Thakar R, Weber AE, Morris CA, Baker LA. Multifunctional carbon nanoelectrodes fabricated by focused ion beam milling. Analyst 2013; 138:5973-82. [PMID: 23942511 DOI: 10.1039/c3an01216f] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
We report a strategy for fabrication of sub-micron, multifunctional carbon electrodes and application of these electrodes as probes for scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM). The fabrication process utilized chemical vapor deposition of parylene, followed by thermal pyrolysis to form conductive carbon and then further deposition of parylene to form an insulation layer. To achieve well-defined electrode geometries, two methods of electrode exposure were utilized. In the first method, carbon probes were masked in polydimethylsiloxane (PDMS) to obtain a cone-shaped electrode. In the second method, the electrode area was exposed via milling with a focused ion beam (FIB) to reveal a carbon ring electrode, carbon ring/platinum disk electrode, or carbon ring/nanopore electrode. Carbon electrodes were batch fabricated (~35/batch) through the vapor deposition process and were characterized with scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), and cyclic voltammetry (CV) measurements. Additionally, Raman spectroscopy was utilized to examine the effects of Ga(+) ion implantation, a result of FIB milling. Constant-height, feedback mode SECM was performed with conical carbon electrodes and carbon ring electrodes. We demonstrate the utility of carbon ring/nanopore electrodes with SECM-SICM to simultaneously collect topography, ion current and electrochemical current images. In addition, carbon ring/nanopore electrodes were utilized in substrate generation/tip collection (SG/TC) SECM. In SG/TC SECM, localized delivery of redox molecules affords a higher resolution, than when the redox molecules are present in the bath solution. Multifunctional geometries of carbon electrode probes will find utility in electroanalytical applications, in general, and more specifically with electrochemical microscopy as discussed herein.
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Affiliation(s)
- Rahul Thakar
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA.
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40
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Dengler AK, McCarty GS. Microfabricated Microelectrode Sensor for Measuring Background and Slowly Changing Dopamine Concentrations. J Electroanal Chem (Lausanne) 2013; 693:28-33. [PMID: 23539293 DOI: 10.1016/j.jelechem.2013.01.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The electrochemical detection of neurotransmitters in vivo has centered on fast scan cyclic voltammetry (FSCV) due to its temporal resolution, sensitivity and chemical selectivity. FSCV is a differential technique that records phasic (second-to-second) changes in the concentration of electroactive neurotransmitters such as dopamine (DA). To isolate the currents due to fluctuations in analyte concentration, in other words to make these phasic measurements, requires the subtraction of a large background current. The subtraction of this background and its volatility renders FSCV unable to determine background or slowly varying concentrations of electroactive analytes. However, there is still a need to readily determine the background and slowly changing concentrations of electroactive analytes in tissue. For example, the background concentrations of DA vary throughout the brain and can affect the dynamics of dopaminergic systems. So, this report presents a microfabricated electrochemical sensor for measuring background and slowly changing concentrations of DA in vitro with the selectivity and sensitivity of FSCV. The sensor is comprised of two microfabricated microelectrodes which are spaced 8 μm apart. Varying the applied potential of the outer electrode manipulates the local concentration of electroactive species including concentration at the inner electrode. These changes are measured at the inner electrode using FSCV. The resulting signal with calibration can determine the background and slowly changing concentration of DA with the selectivity and sensitivity of FSCV. In this study the background of DA is determined in vitro using this sensor. The DA signal is shown to be the result of adsorption/desorption at the outer electrode. Interference from ascorbate on the DA signal is shown to be minimal for this approach.
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Affiliation(s)
- Adam K Dengler
- Department of Biomedical Engineering, North Carolina State University, Raleigh, NC, USA
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41
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Carbon nanofiber multiplexed array and Wireless Instantaneous Neurotransmitter Concentration Sensor for simultaneous detection of dissolved oxygen and dopamine. Biomed Eng Lett 2013; 2:271-277. [PMID: 24688800 DOI: 10.1007/s13534-012-0081-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
PURPOSE While the mechanism of Deep Brain Stimulation (DBS) remains poorly understood, previous studies have shown that it evokes release of neurochemicals and induces activation of functional magnetic resonance imaging (fMRI) blood oxygen level-dependent signal in distinct areas of the brain. Therefore, the main purpose of this paper is to demonstrate the capabilities of the Wireless Instantaneous Neurotransmitter Concentration Sensor system (WINCS) in conjunction with a carbon nanofiber (CNF) multiplexed array electrode as a powerful tool for elucidating the mechanism of DBS through the simultaneous detection of multiple bioactive-molecules. METHODS Patterned CNF nanoelectrode arrays were prepared on a 4-inch silicon wafer where each device consists of 3 × 3 electrode pads, 200 μm square, that contain CNFs spaced at 1μm intervals. The multiplexed carbon nanofiber CNF electrodes were integrated with WINCS to detect mixtures of dopamine (DA) and oxygen (O2) using fast scan cyclic voltammetry (FSCV) in vitro. RESULTS First, simultaneous detection of O2 at two spatially different locations, 200 um apart, was demonstrated. Second, simultaneous detection of both O2 and DA at two spatially different locations, using two different decoupled waveforms was demonstrated. Third, controlled studies demonstrated that the waveform must be interleaved to avoid electrode crosstalk artifacts in the acquired data. CONCLUSIONS Multiplexed CNF nanoelectrode arrays for electrochemical detection of neurotransmitters show promise for the detection of multiple analytes with the application of time independent decoupled waveforms. Electrochemistry on CNF electrodes may be helpful in elucidating the mechanism of DBS, and may also provide the precision and sensitivity required for future applications in feedback modulated DBS neural control systems.
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42
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Roberts JG, Lugo-Morales LZ, Loziuk PL, Sombers LA. Real-time chemical measurements of dopamine release in the brain. Methods Mol Biol 2013; 964:275-94. [PMID: 23296789 DOI: 10.1007/978-1-62703-251-3_16] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Rapid changes in extracellular dopamine concentrations in freely moving or anesthetized rats can be detected using fast-scan cyclic voltammetry (FSCV). Background-subtracted FSCV is a real-time electrochemical technique that can monitor neurochemical transmission in the brain on a subsecond timescale, while providing chemical information on the analyte. Also, this voltammetric approach allows for the investigation of the kinetics of release and uptake of molecules in the brain. This chapter describes, completely, how to make these measurements and the properties of FSCV that make it uniquely suitable for performing chemical measurements of dopaminergic neurotransmission in vivo.
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Affiliation(s)
- James G Roberts
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA
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43
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González-Diéguez N, Colina A, López-Palacios J, Heras A. Spectroelectrochemistry at Screen-Printed Electrodes: Determination of Dopamine. Anal Chem 2012; 84:9146-53. [DOI: 10.1021/ac3018444] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Noelia González-Diéguez
- Department of Chemistry, Universidad de Burgos, Pza. Misael Bañuelos
s/n, E-09001 Burgos, Spain
| | - Alvaro Colina
- Department of Chemistry, Universidad de Burgos, Pza. Misael Bañuelos
s/n, E-09001 Burgos, Spain
| | - Jesús López-Palacios
- Department of Chemistry, Universidad de Burgos, Pza. Misael Bañuelos
s/n, E-09001 Burgos, Spain
| | - Aránzazu Heras
- Department of Chemistry, Universidad de Burgos, Pza. Misael Bañuelos
s/n, E-09001 Burgos, Spain
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44
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Kim BN, Herbst AD, Kim SJ, Minch BA, Lindau M. Parallel recording of neurotransmitters release from chromaffin cells using a 10×10 CMOS IC potentiostat array with on-chip working electrodes. Biosens Bioelectron 2012; 41:736-44. [PMID: 23084756 DOI: 10.1016/j.bios.2012.09.058] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 09/14/2012] [Accepted: 09/27/2012] [Indexed: 02/06/2023]
Abstract
Neurotransmitter release is modulated by many drugs and molecular manipulations. We present an active CMOS-based electrochemical biosensor array with high throughput capability (100 electrodes) for on-chip amperometric measurement of neurotransmitter release. The high-throughput of the biosensor array will accelerate the data collection needed to determine statistical significance of changes produced under varying conditions, from several weeks to a few hours. The biosensor is designed and fabricated using a combination of CMOS integrated circuit (IC) technology and a photolithography process to incorporate platinum working electrodes on-chip. We demonstrate the operation of an electrode array with integrated high-gain potentiostats and output time-division multiplexing with minimum dead time for readout. The on-chip working electrodes are patterned by conformal deposition of Pt and lift-off photolithography. The conformal deposition method protects the underlying electronic circuits from contact with the electrolyte that covers the electrode array during measurement. The biosensor was validated by simultaneous measurement of amperometric currents from 100 electrodes in response to dopamine injection, which revealed the time course of dopamine diffusion along the surface of the biosensor array. The biosensor simultaneously recorded neurotransmitter release successfully from multiple individual living chromaffin cells. The biosensor was capable of resolving small and fast amperometric spikes reporting release from individual vesicle secretions. We anticipate that this device will accelerate the characterization of the modulation of neurotransmitter secretion from neuronal and endocrine cells by pharmacological and molecular manipulations of the cells.
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Affiliation(s)
- Brian N Kim
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA.
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45
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Lama RD, Charlson K, Anantharam A, Hashemi P. Ultrafast Detection and Quantification of Brain Signaling Molecules with Carbon Fiber Microelectrodes. Anal Chem 2012; 84:8096-101. [DOI: 10.1021/ac301670h] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rinchen D. Lama
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United
States
| | - Karl Charlson
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United
States
| | - Arun Anantharam
- Department of Biology, Wayne State University, Detroit, Michigan 48202, United
States
| | - Parastoo Hashemi
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United
States
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46
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Brain dopamine and serotonin differ in regulation and its consequences. Proc Natl Acad Sci U S A 2012; 109:11510-5. [PMID: 22778401 DOI: 10.1073/pnas.1201547109] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dopamine and serotonin (5-hydroxytryptamine or 5-HT) are neurotransmitters that are implicated in many psychological disorders. Although dopamine transmission in the brain has been studied extensively in vivo with fast scan cyclic voltammetry, detection of 5-HT using in vivo voltammetric methods has only recently been established. In this work we use two carbon-fiber microelectrodes to simultaneously measure dopamine release in the nucleus accumbens and 5-HT release in the substantia nigra pars reticulata, using a common stimulation in a single rat. We find that 5-HT release is profoundly restricted in comparison with dopamine release despite comparable tissue content levels. Using physiological and pharmacological analysis, we find that 5-HT transmission is mostly sensitive to uptake and metabolic degradation mechanisms. In contrast, dopamine transmission is constrained by synthesis and repackaging. Finally, we show that disruption of serotonergic regulatory mechanisms by simultaneous inhibition of uptake and metabolic degradation can have severe physiological consequences that mimic serotonin syndrome.
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Flow-injection analysis systems with different detection devices and other related techniques for the in vitro and in vivo determination of dopamine as neurotransmitter. A review. Talanta 2012. [PMID: 23182572 DOI: 10.1016/j.talanta.2012.05.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Dopamine (DA) is one of the most important catecholamine neurotransmitters in the human central nervous system in the brain and plays a key role in the functioning of the renal, hormonal, and cardiovascular systems. Abnormal levels of dopamine are related to neurological disorders, such as schizophrenia and Parkinson's disease and the control and fluctuations of the amount of dopamine are extremely important in monitoring with analytical systems in the human brain. This review covers the attributes of flow-injection analysis systems with different detection devices and other related techniques for the in vitro and in vivo determination of dopamine as neurotransmitter and points out the advantages and disadvantages in the implementation thereof.
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48
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Dumitrescu I, Yancey DF, Crooks RM. Dual-electrode microfluidic cell for characterizing electrocatalysts. LAB ON A CHIP 2012; 12:986-993. [PMID: 22282034 DOI: 10.1039/c2lc21181e] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this paper we introduce a microelectrochemical cell configured for generation-collection experiments and designed primarily for examining the kinetics of electrocatalysts. The heart of the device consists of two, closely spaced, pyrolyzed photoresist microband electrodes enclosed within a microchannel. The cell is suitable for evaluating the efficiency of electrocatalysts under an unprecedented range of conditions. Specifically, compared to the gold-standard rotating ring-disk electrode (RRDE), this device offers four major advantages. First, collection efficiencies of 97% are easily achieved, compared to values of 20-37% that are characteristic of RRDEs. Second, mass transfer coefficients of 0.5 cm s(-1) are accessible for typical redox species, which is significantly higher than RRDEs (up to 0.01 cm s(-1)). Third, we show that the device can operate effectively at temperatures up to 70 °C, which is important for measuring electrochemical kinetics that are relevant to fuel cell catalysts. Finally, much less catalyst and much smaller volumes of electrolyte solution are required to make kinetic measurements using the microelectrochemical device compared to the RRDE. Here, we present the simple procedure used to fabricate the device, fundamental electroanalytical characterization, and electrocatalytic measurements relevant to the oxygen reduction reaction.
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Affiliation(s)
- Ioana Dumitrescu
- Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712-0165, USA
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Jang DP, Kim I, Chang SY, Min HK, Arora K, Marsh MP, Hwang SC, Kimble CJ, Bennet KE, Lee KH. Paired pulse voltammetry for differentiating complex analytes. Analyst 2012; 137:1428-35. [PMID: 22299131 DOI: 10.1039/c2an15912k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Although fast-scan cyclic voltammetry (FSCV) has contributed to important advances in neuroscience research, the technique is encumbered by significant analytical challenges. Confounding factors such as pH change and transient effects at the microelectrode surface make it difficult to discern the analytes represented by complex voltammograms. Here we introduce paired-pulse voltammetry (PPV), that mitigates the confounding factors and simplifies the analytical task. PPV consists of a selected binary waveform with a specific time gap between each of its two comprising pulses, such that each binary wave is repeated, while holding the electrode at a negative potential between the waves. This allows two simultaneous yet very different voltammograms (primary and secondary) to be obtained, each corresponding to the two pulses in the binary waveform. PPV was evaluated in the flow cell to characterize three different analytes, (dopamine, adenosine, and pH changes). The peak oxidation current decreased by approximately 50%, 80%, and 4% for dopamine, adenosine, and pH, in the secondary voltammogram compared with the primary voltammogram, respectively. Thus, the influence of pH changes could be virtually eliminated using the difference between the primary and secondary voltammograms in the PPV technique, which discriminates analytes on the basis of their adsorption characteristics to the carbon fiber electrode. These results demonstrate that PPV can be effectively used for differentiating complex analytes.
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Affiliation(s)
- Dong Pyo Jang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA
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Bhavani Devi L, Berchmans S, Mandal AB. Highly sensitive detection of proteins using voltammetric assay in the presence of silver nanostructures. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2011.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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