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Jeong YH, Kwon M, Shin S, Lee J, Kim KS. Biomedical Applications of CNT-Based Fibers. BIOSENSORS 2024; 14:137. [PMID: 38534244 DOI: 10.3390/bios14030137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 02/29/2024] [Accepted: 03/02/2024] [Indexed: 03/28/2024]
Abstract
Carbon nanotubes (CNTs) have been regarded as emerging materials in various applications. However, the range of biomedical applications is limited due to the aggregation and potential toxicity of powder-type CNTs. To overcome these issues, techniques to assemble them into various macroscopic structures, such as one-dimensional fibers, two-dimensional films, and three-dimensional aerogels, have been developed. Among them, carbon nanotube fiber (CNTF) is a one-dimensional aggregate of CNTs, which can be used to solve the potential toxicity problem of individual CNTs. Furthermore, since it has unique properties due to the one-dimensional nature of CNTs, CNTF has beneficial potential for biomedical applications. This review summarizes the biomedical applications using CNTF, such as the detection of biomolecules or signals for biosensors, strain sensors for wearable healthcare devices, and tissue engineering for regenerating human tissues. In addition, by considering the challenges and perspectives of CNTF for biomedical applications, the feasibility of CNTF in biomedical applications is discussed.
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Affiliation(s)
- Yun Ho Jeong
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Mina Kwon
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Sangsoo Shin
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Jaegeun Lee
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
- Department of Organic Material Science and Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Ki Su Kim
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
- Department of Organic Material Science and Engineering, Pusan National University, Busan 46241, Republic of Korea
- Institute of Advanced Organic Materials, Pusan National University, Busan 46241, Republic of Korea
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2
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Faul EBA, Broussard AM, Rivera DR, Pwint MY, Wu B, Cao Q, Bailey D, Cui XT, Castagnola E. Batch Fabrication of Microelectrode Arrays with Glassy Carbon Microelectrodes and Interconnections for Neurochemical Sensing: Promises and Challenges. MICROMACHINES 2024; 15:277. [PMID: 38399004 PMCID: PMC10892456 DOI: 10.3390/mi15020277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/07/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024]
Abstract
Flexible multielectrode arrays with glassy carbon (GC) electrodes and metal interconnection (hybrid MEAs) have shown promising performance in multi-channel neurochemical sensing. A primary challenge faced by hybrid MEAs fabrication is the adhesion of the metal traces with the GC electrodes, as prolonged electrical and mechanical stimulation can lead to adhesion failure. Previous devices with GC electrodes and interconnects made of a homogeneous material (all GC) demonstrated exceptional electrochemical stability but required miniaturization for enhanced tissue integration and chronic electrochemical sensing. In this study, we used two different methods for the fabrication of all GC-MEAs on thin flexible substrates with miniaturized features. The first method, like that previously reported, involves a double pattern-transfer photolithographic process, including transfer-bonding on temporary polymeric support. The second method requires a double-etching process, which uses a 2 µm-thick low stress silicon nitride coating of the Si wafer as the bottom insulator layer for the MEAs, bypassing the pattern-transfer and demonstrating a novel technique with potential advantages. We confirmed the feasibility of the two fabrication processes by verifying the practical conductivity of 3 µm-wide 2 µm-thick GC traces, the GC microelectrode functionality, and their sensing capability for the detection of serotonin using fast scan cyclic voltammetry. Through the exchange and discussion of insights regarding the strengths and limitations of these microfabrication methods, our goal is to propel the advancement of GC-based MEAs for the next generation of neural interface devices.
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Affiliation(s)
- Emma-Bernadette A. Faul
- Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA 71272, USA; (E.-B.A.F.); (A.M.B.); (D.R.R.)
| | - Austin M. Broussard
- Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA 71272, USA; (E.-B.A.F.); (A.M.B.); (D.R.R.)
| | - Daniel R. Rivera
- Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA 71272, USA; (E.-B.A.F.); (A.M.B.); (D.R.R.)
| | - May Yoon Pwint
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (M.Y.P.); (B.W.); (Q.C.); (X.T.C.)
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Bingchen Wu
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (M.Y.P.); (B.W.); (Q.C.); (X.T.C.)
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Qun Cao
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (M.Y.P.); (B.W.); (Q.C.); (X.T.C.)
| | - Davis Bailey
- Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA 15213, USA;
| | - X. Tracy Cui
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (M.Y.P.); (B.W.); (Q.C.); (X.T.C.)
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15261, USA
- McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219-3110, USA
| | - Elisa Castagnola
- Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA 71272, USA; (E.-B.A.F.); (A.M.B.); (D.R.R.)
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (M.Y.P.); (B.W.); (Q.C.); (X.T.C.)
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3
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Hanser SM, Shao Z, Zhao H, Venton BJ. Electrochemical treatment in KOH improves carbon nanomaterial performance to multiple neurochemicals. Analyst 2024; 149:457-466. [PMID: 38087947 PMCID: PMC10788926 DOI: 10.1039/d3an01710a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 11/22/2023] [Indexed: 01/16/2024]
Abstract
Carbon-fiber microelectrodes (CFMEs) are primarily used to detect neurotransmitters in vivo with fast-scan cyclic voltammetry (FSCV) but other carbon nanomaterial electrodes are being developed. CFME sensitivity to dopamine is improved by applying a constant 1.5 V vs. Ag/AgCl for 3 minutes while dipped in 1 M KOH, which etches the surface and adds oxygen functional groups. However, KOH etching of other carbon nanomaterials and applications to other neurochemicals have not been investigated. Here, we explored KOH etching of CFMEs and carbon nanotube yarn microelectrodes (CNTYMEs) to characterize sensitivity to dopamine, epinephrine, norepinephrine, serotonin, and 3,4-dihydroxyphenylacetic acid (DOPAC). With CNTYMEs, the potential was applied in KOH for 1 minute because the electrode surface cracked with the longer time. KOH treatment increased electrode sensitivity to each cationic neurotransmitter roughly 2-fold for CFMEs, and 2- to 4-fold for CNTYMEs. KOH treatment decreased the background current of the CFMEs by etching the surface carbon; however, KOH-treatment increased the CNTYME background current because the potential separates individual nanotubes. For DOPAC, the current increase was smaller at CNTYMEs because it is anionic and was repelled by the negative holding potential and did not access the crevices. XPS and Raman spectroscopy showed that KOH treatment changed the CNTYME surface chemistry by increasing defect sites and adding oxide functional groups. KOH-treated CNTYMEs had less fouling to serotonin than normal CNTYMEs. Therefore, KOH treatment activates both CFMEs and CNTYMEs and could be used in biological measurements to increase the sensitivity and decrease fouling for neurochemical measurements.
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Affiliation(s)
- Samuel M Hanser
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
| | - Zijun Shao
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
| | - He Zhao
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
| | - B Jill Venton
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
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Ostertag BJ, Ross AE. Editors' Choice-Review-The Future of Carbon-Based Neurochemical Sensing: A Critical Perspective. ECS SENSORS PLUS 2023; 2:043601. [PMID: 38170109 PMCID: PMC10759280 DOI: 10.1149/2754-2726/ad15a2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/06/2023] [Indexed: 01/05/2024]
Abstract
Carbon-based sensors have remained critical materials for electrochemical detection of neurochemicals, rooted in their inherent biocompatibility and broad potential window. Real-time monitoring using fast-scan cyclic voltammetry has resulted in the rise of minimally invasive carbon fiber microelectrodes as the material of choice for making measurements in tissue, but challenges with carbon fiber's innate properties have limited its applicability to understudied neurochemicals. Here, we provide a critical review of the state of carbon-based real-time neurochemical detection and offer insight into ways we envision addressing these limitations in the future. This piece focuses on three main hinderances of traditional carbon fiber based materials: diminished temporal resolution due to geometric properties and adsorption/desorption properties of the material, poor selectivity/specificity to most neurochemicals, and the inability to tune amorphous carbon surfaces for specific interfacial interactions. Routes to addressing these challenges could lie in methods like computational modeling of single-molecule interfacial interactions, expansion to tunable carbon-based materials, and novel approaches to synthesizing these materials. We hope this critical piece does justice to describing the novel carbon-based materials that have preceded this work, and we hope this review provides useful solutions to innovate carbon-based material development in the future for individualized neurochemical structures.
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Affiliation(s)
- Blaise J. Ostertag
- University of Cincinnati, Department of Chemistry, Cincinnati, Ohio 45221-0172, United States of America
| | - Ashley E. Ross
- University of Cincinnati, Department of Chemistry, Cincinnati, Ohio 45221-0172, United States of America
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5
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Zhao H, Shrestha K, Hensley DK, Venton BJ. Carbon nanospikes have improved sensitivity and antifouling properties for adenosine, hydrogen peroxide, and histamine. Anal Bioanal Chem 2023; 415:6039-6050. [PMID: 37505236 PMCID: PMC10867945 DOI: 10.1007/s00216-023-04875-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/11/2023] [Accepted: 07/18/2023] [Indexed: 07/29/2023]
Abstract
Carbon nanospikes (CNSs) are a new nanomaterial that has enhanced surface roughness and surface oxide concentration, increasing the sensitivity for dopamine detection. However, CNS-modified electrodes (CNSMEs) have not been characterized for other neurochemicals, particularly those with higher oxidation potentials. The purpose of this study was to evaluate CNSMEs for the detection of adenosine, hydrogen peroxide (H2O2), and histamine. The sensitivity increased with CNSs, and signals at CNSMEs were about 3.3 times higher than CFMEs. Normalizing for surface area differences using background currents, CNSMEs show an increased signal of 4.8 times for adenosine, 1.5 times for H2O2, and 2 times for histamine. CNSMEs promoted the formation of secondary products for adenosine and histamine, which enables differentiation from other analytes with similar oxidation potentials. CNSs also selectively enhance the sensitivity for adenosine and histamine compared to H2O2. A scan rate test reveals that adenosine is more adsorption-controlled at CNS electrodes than CFMEs. CNSMEs are antifouling for histamine, with less fouling because the polymers formed after histamine electrooxidation do not adsorb due to an elevated number of edge planes. CNSMEs were useful for detecting each analyte applied in brain slices. Because of the hydrophilic surface compared to CFMEs, CNSMEs also have reduced biofouling when used in tissue. Therefore, CNSMEs are useful for tissue measurements of adenosine, hydrogen peroxide, and histamine with high selectivity and low fouling.
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Affiliation(s)
- He Zhao
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22901, USA
| | - Kailash Shrestha
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22901, USA
| | - Dale K Hensley
- Center for Nanophase Materials Sciences, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - B Jill Venton
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22901, USA.
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6
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Jarosova R, Ostertag BJ, Ross AE. Graphene oxide fiber microelectrodes with controlled sheet alignment for sensitive neurotransmitter detection. NANOSCALE 2023; 15:15249-15258. [PMID: 37672207 DOI: 10.1039/d3nr02879h] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Here, we synthesized and characterized graphene oxide (GO) fiber microelectrodes with controllable nanosheet orientation to study the extent to which sheet alignment and orientation impacts electrochemical detection of neurochemicals. The alignment of the GO nanosheets was characterized by scanning electron microscopy, Raman spectroscopy, and cyclic voltammetry. The electrochemical performance of GO microelectrodes and its suitability for subsecond detection of neurotransmitters was further evaluated by fast-scan cyclic voltammetry (FSCV). We have shown that the GO sheet alignment has a considerable effect on the electron transfer kinetics, frequency independent behavior, and detection suitability for specific neurotransmitters. Therefore, this fine-tuning aspect of the electrode surface for specific electrochemical detection should be taken into consideration for any future utilization of GO-based biological sensors.
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Affiliation(s)
- Romana Jarosova
- University of Cincinnati, Department of Chemistry, 312 College Dr, 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Blaise J Ostertag
- University of Cincinnati, Department of Chemistry, 312 College Dr, 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Ashley E Ross
- University of Cincinnati, Department of Chemistry, 312 College Dr, 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
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7
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Castagnola E, Robbins EM, Krahe DD, Wu B, Pwint MY, Cao Q, Cui XT. Stable in-vivo electrochemical sensing of tonic serotonin levels using PEDOT/CNT-coated glassy carbon flexible microelectrode arrays. Biosens Bioelectron 2023; 230:115242. [PMID: 36989659 PMCID: PMC10101938 DOI: 10.1016/j.bios.2023.115242] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/13/2023] [Accepted: 03/19/2023] [Indexed: 03/29/2023]
Abstract
Chronic sampling of tonic serotonin (5-hydroxytryptamine, 5-HT) concentrations in the brain is critical for tracking neurological disease development and the time course of pharmacological treatments. Despite their value, in vivo chronic multi-site measurements of tonic 5-HT have not been reported. To fill this technological gap, we batch-fabricated implantable glassy carbon (GC) microelectrode arrays (MEAs) onto a flexible SU-8 substrate to provide an electrochemically stable and biocompatible device/tissue interface. To achieve detection of tonic 5-HT concentrations, we applied a poly(3,4-ethylenedioxythiophene)/carbon nanotube (PEDOT/CNT) electrode coating and optimized a square wave voltammetry (SWV) waveform for selective 5-HT measurement. In vitro, the PEDOT/CNT-coated GC microelectrodes achieved high sensitivity to 5-HT, good fouling resistance, and excellent selectivity against the most common neurochemical interferents. In vivo, our PEDOT/CNT-coated GC MEAs successfully detected basal 5-HT concentrations at different locations within the CA2 region of the hippocampus of both anesthetized and awake mice. Furthermore, the PEDOT/CNT-coated MEAs were able to detect tonic 5-HT in the mouse hippocampus for one week after implantation. Histology reveals that the flexible GC MEA implants caused less tissue damage and reduced inflammatory response in the hippocampus compared to commercially available stiff silicon probes. To the best of our knowledge, this PEDOT/CNT-coated GC MEA is the first implantable, flexible sensor capable of chronic in vivo multi-site sensing of tonic 5-HT.
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Affiliation(s)
- Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA; Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA, 818 Nelson Ave, 71272, USA
| | - Elaine M Robbins
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA
| | - Daniela D Krahe
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA
| | - Bingchen Wu
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA; Center for Neural Basis of Cognition, University of Pittsburgh, 4400 Fifth Ave, PA 15213, Pittsburgh, PA, 15261, USA
| | - May Yoon Pwint
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA; Center for Neural Basis of Cognition, University of Pittsburgh, 4400 Fifth Ave, PA 15213, Pittsburgh, PA, 15261, USA
| | - Qun Cao
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260, Pittsburgh, PA, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive, Pittsburgh, PA, 15219-3110, USA; Center for Neural Basis of Cognition, University of Pittsburgh, 4400 Fifth Ave, PA 15213, Pittsburgh, PA, 15261, USA.
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8
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Castagnola E, Robbins EM, Krahe D, Wu B, Pwint MY, Cao Q, Cui XT. Implantable flexible multielectrode arrays for multi-site sensing of serotonin tonic levels. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.17.524488. [PMID: 36711655 PMCID: PMC9882191 DOI: 10.1101/2023.01.17.524488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Real-time multi-channel measurements of tonic serotonin (5-hydroxytryptamine, 5-HT) concentrations across different brain regions are of utmost importance to the understanding of 5-HT’s role in anxiety, depression, and impulse control disorders, which will improve the diagnosis and treatment of these neuropsychiatric illnesses. Chronic sampling of 5-HT is critical in tracking disease development as well as the time course of pharmacological treatments. Despite their value, in vivo chronic multi-site measurements of 5-HT have not been reported. To fill this technological gap, we batch fabricated implantable glassy carbon (GC) microelectrode arrays (MEAs) on a flexible SU-8 substrate to provide an electrochemically stable and biocompatible device/tissue interface. Then, to achieve multi-site detection of tonic 5-HT concentrations, we incorporated the poly(3,4-ethylenedioxythiophene)/functionalized carbon nanotube (PEDOT/CNT) coating on the GC microelectrodes in combination with a new square wave voltammetry (SWV) approach, optimized for selective 5-HT measurement. In vitro , the PEDOT/CNT coated GC microelectrodes achieved high sensitivity towards 5-HT, good fouling resistance in the presence of 5-HT, and excellent selectivity towards the most common neurochemical interferents. In vivo , our PEDOT/CNT-coated GC MEAs were able to successfully detect basal 5-HT concentrations at different locations of the CA2 hippocampal region of mice in both anesthetized and awake head-fixed conditions. Furthermore, the implanted PEDOT/CNT-coated MEA achieved stable detection of tonic 5-HT concentrations for one week. Finally, histology data in the hippocampus shows reduced tissue damage and inflammatory responses compared to stiff silicon probes. To the best of our knowledge, this PEDOT/CNT-coated GC MEA is the first implantable flexible multisite sensor capable of chronic in vivo multi-site sensing of tonic 5-HT. This implantable MEA can be custom-designed according to specific brain region of interests and research questions, with the potential to combine electrophysiology recording and multiple analyte sensing to maximize our understanding of neurochemistry. Highlights PEDOT/CNT-coated GC microelectrodes enabled sensitive and selective tonic detection of serotonin (5-HT) using a new square wave voltammetry (SWV) approach PEDOT/CNT-coated GC MEAs achieved multi-site in vivo 5-HT tonic detection for one week. Flexible MEAs lead to reduced tissue damage and inflammation compared to stiff silicon probes.
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Wang S, Liu Y, Zhu A, Tian Y. In Vivo Electrochemical Biosensors: Recent Advances in Molecular Design, Electrode Materials, and Electrochemical Devices. Anal Chem 2023; 95:388-406. [PMID: 36625112 DOI: 10.1021/acs.analchem.2c04541] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Electrochemical biosensors provide powerful tools for dissecting the dynamically changing neurochemical signals in the living brain, which contribute to the insight into the physiological and pathological processes of the brain, due to their high spatial and temporal resolutions. Recent advances in the integration of in vivo electrochemical sensors with cross-disciplinary advances have reinvigorated the development of in vivo sensors with even better performance. In this Review, we summarize the recent advances in molecular design, electrode materials, and electrochemical devices for in vivo electrochemical sensors from molecular to macroscopic dimensions, highlighting the methods to obtain high performance for fulfilling the requirements for determination in the complex brain through flexible and smart design of molecules, materials, and devices. Also, we look forward to the development of next-generation in vivo electrochemical biosensors.
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Affiliation(s)
- Shidi Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
| | - Yuandong Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
| | - Anwei Zhu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
| | - Yang Tian
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
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10
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Shao Z, Chang Y, Venton BJ. Carbon microelectrodes with customized shapes for neurotransmitter detection: A review. Anal Chim Acta 2022; 1223:340165. [PMID: 35998998 PMCID: PMC9867599 DOI: 10.1016/j.aca.2022.340165] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/08/2022] [Accepted: 07/09/2022] [Indexed: 01/26/2023]
Abstract
Carbon is a popular electrode material for neurotransmitter detection due to its good electrochemical properties, high biocompatibility, and inert chemistry. Traditional carbon electrodes, such as carbon fibers, have smooth surfaces and fixed shapes. However, newer studies customize the shape and nanostructure the surface to enhance electrochemistry for different applications. In this review, we show how changing the structure of carbon electrodes with methods such as chemical vapor deposition (CVD), wet-etching, direct laser writing (DLW), and 3D printing leads to different electrochemical properties. The customized shapes include nanotips, complex 3D structures, porous structures, arrays, and flexible sensors with patterns. Nanostructuring enhances sensitivity and selectivity, depending on the carbon nanomaterial used. Carbon nanoparticle modifications enhance electron transfer kinetics and prevent fouling for neurochemicals that are easily polymerized. Porous electrodes trap analyte momentarily on the scale of an electrochemistry experiment, leading to thin layer electrochemical behavior that enhances secondary peaks from chemical reactions. Similar thin layer cell behavior is observed at cavity carbon nanopipette electrodes. Nanotip electrodes facilitate implantation closer to the synapse with reduced tissue damage. Carbon electrode arrays are used to measure from multiple neurotransmitter release sites simultaneously. Custom-shaped carbon electrodes are enabling new applications in neuroscience, such as distinguishing different catecholamines by secondary peaks, detection of vesicular release in single cells, and multi-region measurements in vivo.
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Affiliation(s)
- Zijun Shao
- Dept. of Chemistry, University of Virginia, Charlottesville, VA, 22904-4319, USA
| | - Yuanyu Chang
- Dept. of Chemistry, University of Virginia, Charlottesville, VA, 22904-4319, USA
| | - B Jill Venton
- Dept. of Chemistry, University of Virginia, Charlottesville, VA, 22904-4319, USA.
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11
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Seki M, Wada R, Muguruma H. Electrochemical behavior of intramolecular cyclization reaction of catecholamines at carbon nanotube/carboxymethylcellulose electrode. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Castagnola E, Robbins EM, Wu B, Pwint MY, Garg R, Cohen-Karni T, Cui XT. Flexible Glassy Carbon Multielectrode Array for In Vivo Multisite Detection of Tonic and Phasic Dopamine Concentrations. BIOSENSORS 2022; 12:540. [PMID: 35884343 PMCID: PMC9312827 DOI: 10.3390/bios12070540] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 07/13/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Dopamine (DA) plays a central role in the modulation of various physiological brain functions, including learning, motivation, reward, and movement control. The DA dynamic occurs over multiple timescales, including fast phasic release, as a result of neuronal firing and slow tonic release, which regulates the phasic firing. Real-time measurements of tonic and phasic DA concentrations in the living brain can shed light on the mechanism of DA dynamics underlying behavioral and psychiatric disorders and on the action of pharmacological treatments targeting DA. Current state-of-the-art in vivo DA detection technologies are limited in either spatial or temporal resolution, channel count, longitudinal stability, and ability to measure both phasic and tonic dynamics. We present here an implantable glassy carbon (GC) multielectrode array on a SU-8 flexible substrate for integrated multichannel phasic and tonic measurements of DA concentrations. The GC MEA demonstrated in vivo multichannel fast-scan cyclic voltammetry (FSCV) detection of electrically stimulated phasic DA release simultaneously at different locations of the mouse dorsal striatum. Tonic DA measurement was enabled by coating GC electrodes with poly(3,4-ethylenedioxythiophene)/carbon nanotube (PEDOT/CNT) and using optimized square-wave voltammetry (SWV). Implanted PEDOT/CNT-coated MEAs achieved stable detection of tonic DA concentrations for up to 3 weeks in the mouse dorsal striatum. This is the first demonstration of implantable flexible MEA capable of multisite electrochemical sensing of both tonic and phasic DA dynamics in vivo with chronic stability.
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Affiliation(s)
- Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (E.C.); (E.M.R.); (B.W.); (M.Y.P.)
| | - Elaine M. Robbins
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (E.C.); (E.M.R.); (B.W.); (M.Y.P.)
| | - Bingchen Wu
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (E.C.); (E.M.R.); (B.W.); (M.Y.P.)
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - May Yoon Pwint
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (E.C.); (E.M.R.); (B.W.); (M.Y.P.)
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Raghav Garg
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA; (R.G.); (T.C.-K.)
| | - Tzahi Cohen-Karni
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA; (R.G.); (T.C.-K.)
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (E.C.); (E.M.R.); (B.W.); (M.Y.P.)
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15261, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
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13
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Jia Q, Venton BJ, DuBay KH. Structure and Dynamics of Adsorbed Dopamine on Solvated Carbon Nanotubes and in a CNT Groove. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123768. [PMID: 35744896 PMCID: PMC9228466 DOI: 10.3390/molecules27123768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/01/2022] [Accepted: 06/06/2022] [Indexed: 11/29/2022]
Abstract
Advanced carbon microelectrodes, including many carbon-nanotube (CNT)-based electrodes, are being developed for the in vivo detection of neurotransmitters such as dopamine (DA). Our prior simulations of DA and dopamine-o-quinone (DOQ) on pristine, flat graphene showed rapid surface diffusion for all adsorbed species, but it is not known how CNT surfaces affect dopamine adsorption and surface diffusivity. In this work, we use molecular dynamics simulations to investigate the adsorbed structures and surface diffusion dynamics of DA and DOQ on CNTs of varying curvature and helicity. In addition, we study DA dynamics in a groove between two aligned CNTs to model the spatial constraints at the junctions within CNT assemblies. We find that the adsorbate diffusion on a solvated CNT surface depends upon curvature. However, this effect cannot be attributed to changes in the surface energy roughness because the lateral distributions of the molecular adsorbates are similar across curvatures, diffusivities on zigzag and armchair CNTs are indistinguishable, and the curvature dependence disappears in the absence of solvent. Instead, adsorbate diffusivities correlate with the vertical placement of the adsorbate’s moieties, its tilt angle, its orientation along the CNT axis, and the number of waters in its first hydration shell, all of which will influence its effective hydrodynamic radius. Finally, DA diffuses into and remains in the groove between a pair of aligned and solvated CNTs, enhancing diffusivity along the CNT axis. These first studies of surface diffusion on a CNT electrode surface are important for understanding the changes in diffusion dynamics of dopamine on nanostructured carbon electrode surfaces.
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14
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Tringides CM, Mooney DJ. Materials for Implantable Surface Electrode Arrays: Current Status and Future Directions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2107207. [PMID: 34716730 DOI: 10.1002/adma.202107207] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Surface electrode arrays are mainly fabricated from rigid or elastic materials, and precisely manipulated ductile metal films, which offer limited stretchability. However, the living tissues to which they are applied are nonlinear viscoelastic materials, which can undergo significant mechanical deformation in dynamic biological environments. Further, the same arrays and compositions are often repurposed for vastly different tissues rather than optimizing the materials and mechanical properties of the implant for the target application. By first characterizing the desired biological environment, and then designing a technology for a particular organ, surface electrode arrays may be more conformable, and offer better interfaces to tissues while causing less damage. Here, the various materials used in each component of a surface electrode array are first reviewed, and then electrically active implants in three specific biological systems, the nervous system, the muscular system, and skin, are described. Finally, the fabrication of next-generation surface arrays that overcome current limitations is discussed.
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Affiliation(s)
- Christina M Tringides
- Harvard Program in Biophysics, Harvard University, Cambridge, MA, 02138, USA
- Harvard-MIT Division in Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02138, USA
| | - David J Mooney
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02138, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
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15
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Guo Y, Chen C, Feng J, Wang L, Wang J, Tang C, Sun X, Peng H. An Anti-Biofouling Flexible Fiber Biofuel Cell Working in the Brain. SMALL METHODS 2022; 6:e2200142. [PMID: 35322598 DOI: 10.1002/smtd.202200142] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/09/2022] [Indexed: 06/14/2023]
Abstract
Biofuel cell (BFC) that transfers chemical energy into electricity is a promising candidate as an energy-harvesting device for implantable electronics. However, there still remain major challenges for implantable BFCs, including bulky and rigid device structure mismatching with soft tissues such as the brain, and the power output decreases due to the fouling process in a biological environment. Here, a flexible and anti-biofouling fiber BFC working in the brain chronically is developed. The fiber BFC is based on a carbon nanotube fiber electrode to possess small size and flexibility. A hydrophilic zwitterionic anti-biofouling polydopamine-2-methacryloyloxyethyl phosphorylcholine layer is designed on the surface of fiber BFC to resist the nonspecific protein adsorption in a complex biological environment. After implantation, the fiber BFC can achieve a stable device/tissue interface, along with a negligible immune response. The fiber BFC has first realized power generation in the mouse brain for over a month, exhibiting its promising prospect as an energy-harvesting device in vivo.
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Affiliation(s)
- Yue Guo
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Chuanrui Chen
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Jianyou Feng
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Liyuan Wang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Jiajia Wang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Chengqiang Tang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Xuemei Sun
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
| | - Huisheng Peng
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China
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16
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Li Y, Jarosova R, Weese-Myers ME, Ross AE. Graphene-Fiber Microelectrodes for Ultrasensitive Neurochemical Detection. Anal Chem 2022; 94:4803-4812. [PMID: 35274933 DOI: 10.1021/acs.analchem.1c05637] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Here, we have synthesized and characterized graphene-fiber microelectrodes (GFME's) for subsecond detection of neurochemicals with fast-scan cyclic voltammetry (FSCV) for the first time. GFME's exhibited extraordinary properties including faster electron transfer kinetics, significantly improved sensitivity, and ease of tunability that we anticipate will have major impacts on neurochemical detection for years to come. GF's have been used in the literature for various applications; however, scaling their size down to microelectrodes and implementing them as neurochemical microsensors is significantly less developed. The GF's developed in this paper were on average 20-30 μm in diameter and both graphene oxide (GO) and reduced graphene oxide (rGO) fibers were characterized with FSCV. Neat GF's were synthesized using a one-step dimension-confined hydrothermal strategy. FSCV detection has traditionally used carbon-fiber microelectrodes (CFME's) and more recently carbon nanotube fiber electrodes; however, uniform functionalization and direct control of the 3D surface structure of these materials remain limited. The expansion to GFME's will certainly open new avenues for fine-tuning the electrode surface for specific electrochemical detection. When comparing to traditional CFME's, our GFME's exhibited significant increases in electron transfer, redox cycling, fouling resistance, higher sensitivity, and frequency independent behavior which demonstrates their incredible utility as biological sensors.
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Affiliation(s)
- Yuxin Li
- Department of Chemistry, University of Cincinnati, 312 College Drive 404 Crosley Tower, Cincinnati, Ohio 45221-0172, United States
| | - Romana Jarosova
- Department of Chemistry, University of Cincinnati, 312 College Drive 404 Crosley Tower, Cincinnati, Ohio 45221-0172, United States
| | - Moriah E Weese-Myers
- Department of Chemistry, University of Cincinnati, 312 College Drive 404 Crosley Tower, Cincinnati, Ohio 45221-0172, United States
| | - Ashley E Ross
- Department of Chemistry, University of Cincinnati, 312 College Drive 404 Crosley Tower, Cincinnati, Ohio 45221-0172, United States
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17
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Ostertag BJ, Cryan MT, Serrano JM, Liu G, Ross AE. Porous Carbon Nanofiber-Modified Carbon Fiber Microelectrodes for Dopamine Detection. ACS APPLIED NANO MATERIALS 2022; 5:2241-2249. [PMID: 36203493 PMCID: PMC9531868 DOI: 10.1021/acsanm.1c03933] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present a method to modify carbon-fiber microelectrodes (CFME) with porous carbon nanofibers (PCFs) to improve detection and to investigate the impact of porous geometry for dopamine detection with fast-scan cyclic voltammetry (FSCV). PCFs were fabricated by electrospinning, carbonizing, and pyrolyzing poly(acrylonitrile)-b-poly(methyl methacrylate) (PAN-b-PMMA) block copolymer nanofiber frameworks. Commonly, porous nanofibers are used for energy storage applications, but we present an application of these materials for biosensing which has not been previously studied. This modification impacted the topology and enhanced redox cycling at the surface. PCF modifications increased the oxidative current for dopamine 2.0 ± 0.1-fold (n = 33) with significant increases in detection sensitivity. PCF are known to have more edge plane sites which we speculate lead to the two-fold increase in electroactive surface area. Capacitive current changes were negligible providing evidence that improvements in detection are due to faradaic processes at the electrode. The ΔEp for dopamine decreased significantly at modified CFMEs. Only a 2.2 ± 2.2 % change in dopamine current was observed after repeated measurements and only 10.5 ± 2.8% after 4 hours demonstrating the stability of the modification over time. We show significant improvements in norepinephrine, ascorbic acid, adenosine, serotonin, and hydrogen peroxide detection. Lastly, we demonstrate that the modified electrodes can detect endogenous, unstimulated release of dopamine in living slices of rat striatum. Overall, we provide evidence that porous nanostructures significantly improve neurochemical detection with FSCV and echo the necessity for investigating the extent to which geometry impacts electrochemical detection.
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Affiliation(s)
- Blaise J. Ostertag
- University of Cincinnati, Department of Chemistry, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA
| | - Michael T. Cryan
- University of Cincinnati, Department of Chemistry, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA
| | - Joel M. Serrano
- Virginia Polytechnic Institute and State University, Department of Chemistry, Macromolecules Innovation Institute, Division of Nanoscience, Academy of Integrated Science, 800 West Campus Dr., Blacksburg, VA, 2406, USA
| | - Guoliang Liu
- Virginia Polytechnic Institute and State University, Department of Chemistry, Macromolecules Innovation Institute, Division of Nanoscience, Academy of Integrated Science, 800 West Campus Dr., Blacksburg, VA, 2406, USA
| | - Ashley E. Ross
- University of Cincinnati, Department of Chemistry, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA
- Corresponding author: Office Phone#: 513-556-9314,
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18
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Jia Q, Yang C, Venton BJ, DuBay KH. Atomistic Simulations of Dopamine Diffusion Dynamics on a Pristine Graphene Surface. Chemphyschem 2022; 23:e202100783. [PMID: 34939307 PMCID: PMC9933135 DOI: 10.1002/cphc.202100783] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/04/2021] [Indexed: 11/08/2022]
Abstract
Carbon microelectrodes enable in vivo detection of neurotransmitters, and new electrodes aim to optimize the carbon surface. However, atomistic detail on the diffusion and orientation of neurotransmitters near these surfaces is lacking. Here, we employ molecular dynamics simulations to investigate the surface diffusion of dopamine (DA), its oxidation product dopamine-o-quinone (DOQ), and their protonated forms on the pristine basal plane of flat graphene. We find that all DA species rapidly adsorb to the surface and remain adsorbed, even without a holding potential or graphene surface defects. We also find that the diffusivities of the adsorbed and the fully solvated DA are similar and that the protonated species diffuse more slowly on the surface than their corresponding neutral forms, while the oxidized species diffuse more rapidly. Structurally, we find that the underlying graphene lattice has little influence over the molecular adsorbate's lateral position, and the vertical placement of the amine group on dopamine is highly dependent upon its charge. Finally, we find that solvation has a large effect on surface diffusivities. These first results from molecular dynamics simulations of dopamine at the aqueous-graphene interface show that dopamine diffuses rapidly on the surface, even without an applied potential, and provide a basis for future simulations of neurotransmitter structure and dynamics on advanced carbon materials electrodes.
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19
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Syeed AJ, Li Y, Ostertag BJ, Brown JW, Ross AE. Nanostructured carbon-fiber surfaces for improved neurochemical detection. Faraday Discuss 2021; 233:336-353. [PMID: 34935021 PMCID: PMC9125946 DOI: 10.1039/d1fd00049g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fundamental insight into the extent to which the nanostructured surface and geometry impacts neurochemical interactions at electrode surfaces could provide significant advances in our ability to design and fabricate ultrasensitive neurochemical detection probes. Here, we investigate the extent to which the nanostructure of the carbon-fiber surface impacts detection of catecholamines and purines with fast-scan cyclic voltammetry (FSCV). Carbon-fibers were treated with argon (Ar) plasma to induce variations in the nano- and micro-structure without changing the functionalization of the surface. We tested variations in topology by measuring the extent to which the flow rate, RF power, and treatment time affect the surface roughness. Flow rates from 50-100 sccm, plasma power from 20-100 W, and treatment times from 30 s to 5 min were compared. Two Ar-treatments were chosen from the optimization studies for comparison, and the surface roughness was evaluated using atomic force microscopy (AFM). To ensure no changes in chemical composition, fibers were analyzed with X-ray photoelectron spectroscopy (XPS). On average, at the optimized Ar-plasma treatment procedure, oxidative current for adenosine and ATP increased by 3.5 ± 1.4-fold and 3.2 ± 0.6-fold, and guanosine and GTP by 1.7 ± 0.3-fold and 1.8 ± 0.3-fold, respectively (n = 9). Dopamine increased by 1.7 ± 0.3-fold. The extent to which changes in the electrode structure impact adsorption, sensitivity, and electron transfer rates were measured. A COMSOL Multiphysics simulation was developed to enable the modeling of mass transport of electroactive species at varying electrode geometries. Overall, this study provides critical insight into the extent to which the nanostructure of the surface impacts the electrochemical detection of neurochemicals.
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Affiliation(s)
- Ayah J Syeed
- University of Cincinnati, Department of Chemistry, 312 College Dr 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Yuxin Li
- University of Cincinnati, Department of Chemistry, 312 College Dr 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Blaise J Ostertag
- University of Cincinnati, Department of Chemistry, 312 College Dr 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Jared W Brown
- University of Cincinnati, Department of Chemistry, 312 College Dr 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Ashley E Ross
- University of Cincinnati, Department of Chemistry, 312 College Dr 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
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20
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Devi M, Vomero M, Fuhrer E, Castagnola E, Gueli C, Nimbalkar S, Hirabayashi M, Kassegne S, Stieglitz T, Sharma S. Carbon-based neural electrodes: promises and challenges. J Neural Eng 2021; 18. [PMID: 34404037 DOI: 10.1088/1741-2552/ac1e45] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 08/17/2021] [Indexed: 01/01/2023]
Abstract
Neural electrodes are primary functional elements of neuroelectronic devices designed to record neural activity based on electrochemical signals. These electrodes may also be utilized for electrically stimulating the neural cells, such that their response can be simultaneously recorded. In addition to being medically safe, the electrode material should be electrically conductive and electrochemically stable under harsh biological environments. Mechanical flexibility and conformability, resistance to crack formation and compatibility with common microfabrication techniques are equally desirable properties. Traditionally, (noble) metals have been the preferred for neural electrode applications due to their proven biosafety and a relatively high electrical conductivity. Carbon is a recent addition to this list, which is far superior in terms of its electrochemical stability and corrosion resistance. Carbon has also enabled 3D electrode fabrication as opposed to the thin-film based 2D structures. One of carbon's peculiar aspects is its availability in a wide range of allotropes with specialized properties that render it highly versatile. These variations, however, also make it difficult to understand carbon itself as a unique material, and thus, each allotrope is often regarded independently. Some carbon types have already shown promising results in bioelectronic medicine, while many others remain potential candidates. In this topical review, we first provide a broad overview of the neuroelectronic devices and the basic requirements of an electrode material. We subsequently discuss the carbon family of materials and their properties that are useful in neural applications. Examples of devices fabricated using bulk and nano carbon materials are reviewed and critically compared. We then summarize the challenges, future prospects and next-generation carbon technology that can be helpful in the field of neural sciences. The article aims at providing a common platform to neuroscientists, electrochemists, biologists, microsystems engineers and carbon scientists to enable active and comprehensive efforts directed towards carbon-based neuroelectronic device fabrication.
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Affiliation(s)
- Mamta Devi
- School of Engineering, Indian Institute of Technology Mandi, Kamand, Himachal Pradesh 175075, India
| | - Maria Vomero
- Bioelectronic Systems Laboratory, Columbia University, 500 West 120th Street, New York, NY 10027, United States of America
| | - Erwin Fuhrer
- School of Computing and Electrical Engineering, Indian Institute of Technology Mandi, Kamand, Himachal Pradesh 175075 India
| | - Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, United States of America
| | - Calogero Gueli
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering-IMTEK, University of Freiburg, Georges-Koehler-Allee 080, 79110 Freiburg, Germany
| | - Surabhi Nimbalkar
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, San Diego State University and NSF-ERC Center for Neurotechnology (CNT), 5500 Campanile Drive, San Diego, CA 92182, United States of America
| | - Mieko Hirabayashi
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, San Diego State University and NSF-ERC Center for Neurotechnology (CNT), 5500 Campanile Drive, San Diego, CA 92182, United States of America
| | - Sam Kassegne
- NanoFAB.SDSU Research Lab, Department of Mechanical Engineering, San Diego State University and NSF-ERC Center for Neurotechnology (CNT), 5500 Campanile Drive, San Diego, CA 92182, United States of America
| | - Thomas Stieglitz
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering-IMTEK, University of Freiburg, Georges-Koehler-Allee 080, 79110 Freiburg, Germany.,BrainLinks-BrainTools Center, University of Freiburg, Georges-Koehler-Allee 080, 79110 Freiburg, Germany.,Bernstein Center Freiburg, University of Freiburg, Hansastr. 9a, 79104 Freiburg, Germany
| | - Swati Sharma
- School of Engineering, Indian Institute of Technology Mandi, Kamand, Himachal Pradesh 175075, India
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21
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Castagnola E, Garg R, Rastogi SK, Cohen-Karni T, Cui XT. 3D fuzzy graphene microelectrode array for dopamine sensing at sub-cellular spatial resolution. Biosens Bioelectron 2021; 191:113440. [PMID: 34171734 DOI: 10.1016/j.bios.2021.113440] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/28/2021] [Accepted: 06/13/2021] [Indexed: 02/07/2023]
Abstract
The development of a high sensitivity real-time sensor for multi-site detection of dopamine (DA) with high spatial and temporal resolution is of fundamental importance to study the complex spatial and temporal pattern of DA dynamics in the brain, thus improving the understanding and treatments of neurological and neuropsychiatric disorders. In response to this need, here we present high surface area out-of-plane grown three-dimensional (3D) fuzzy graphene (3DFG) microelectrode arrays (MEAs) for highly selective, sensitive, and stable DA electrochemical sensing. 3DFG microelectrodes present a remarkable sensitivity to DA (2.12 ± 0.05 nA/nM, with LOD of 364.44 ± 8.65 pM), the highest reported for nanocarbon MEAs using Fast Scan Cyclic Voltammetry (FSCV). The high surface area of 3DFG allows for miniaturization of electrode down to 2 × 2 μm2, without compromising the electrochemical performance. Moreover, 3DFG MEAs are electrochemically stable under 7.2 million scans of continuous FSCV cycling, present exceptional selectivity over the most common interferents in vitro with minimum fouling by electrochemical byproducts and can discriminate DA and serotonin (5-HT) in response to the injection of their 50:50 mixture. These results highlight the potential of 3DFG MEAs as a promising platform for FSCV based multi-site detection of DA with high sensitivity, selectivity, and spatial resolution.
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Affiliation(s)
- Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260 Pittsburgh, PA, USA
| | - Raghav Garg
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Sahil K Rastogi
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Tzahi Cohen-Karni
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA; Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive Pittsburgh, PA, 15219-3110, USA.
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260 Pittsburgh, PA, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive Pittsburgh, PA, 15219-3110, USA; Center for Neural Basis of Cognition, University of Pittsburgh, 4400 Fifth Ave, Pittsburgh, PA 15213, Pittsburgh, PA, 15261, USA.
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22
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Gupta P, Rahm CE, Griesmer B, Alvarez NT. Carbon Nanotube Microelectrode Set: Detection of Biomolecules to Heavy Metals. Anal Chem 2021; 93:7439-7448. [PMID: 33988989 DOI: 10.1021/acs.analchem.1c00360] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
An ultrasensitive electrochemical microelectrode set (μ-ES), where all three electrodes are made of highly densified carbon nanotube fiber (HD-CNTf) cross sections (length ∼40 μm), embedded in an inert polymer matrix, and exposed open-ended CNTs at the interface, is presented here. Bare open ends of HD-CNTf rods were used as the working (∼40 μm diameter) and counter (∼94 μm diameter) electrodes, while the cross section of a ∼94 μm diameter was electroplated with Ag/AgCl and coated with Nafion to employ as a quasi-reference electrode. The Ag/AgCl/Nafion-coated HD-CNTf rod quasi-reference electrode provided a very stable potential comparable to the commercial porous-junction Ag/AgCl reference electrode. The HD-CNTf rod μ-ES has been evaluated by electrochemical determination of biologically important analytes, i.e., dopamine (DA), β-nicotinamide adenine dinucleotide (NADH), a diuretic drug, i.e., furosemide, and a heavy metal, i.e., lead ions (Pb2+). Different voltammetric techniques were employed during the study, i.e., cyclic voltammetry (CV), square wave voltammetry (SWV), amperometry, and square wave anodic stripping voltammetry (SWASV). The direct metallic connection to CNTs gives access to the exceptional properties of highly ordered open-ended CNTs as electrochemical sensors. The distinct structural and electronic properties of aligned HD-CNTf rods in the μ-ES demonstrate fast electron transfer kinetics and offer excellent detection performance during testing for different analytes with wide linear ranges, excellent sensitivity, and very low limits of detection.
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Affiliation(s)
- Pankaj Gupta
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Connor E Rahm
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Benjamin Griesmer
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Noe T Alvarez
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
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23
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Rafi H, Zestos AG. Review-Recent Advances in FSCV Detection of Neurochemicals via Waveform and Carbon Microelectrode Modification. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2021; 168:057520. [PMID: 34108735 PMCID: PMC8186302 DOI: 10.1149/1945-7111/ac0064] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Fast scan cyclic voltammetry (FSCV) is an analytical technique that was first developed over 30 years ago. Since then, it has been extensively used to detect dopamine using carbon fiber microelectrodes (CFMEs). More recently, electrode modifications and waveform refinement have enabled the detection of a wider variety of neurochemicals including nucleosides such as adenosine and guanosine, neurotransmitter metabolites of dopamine, and neuropeptides such as enkephalin. These alterations have facilitated the selectivity of certain biomolecules over others to enhance the measurement of the analyte of interest while excluding interferants. In this review, we detail these modifications and how specializing CFME sensors allows neuro-analytical researchers to develop tools to understand the neurochemistry of the brain in disease states and provide groundwork for translational work in clinical settings.
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Affiliation(s)
- Harmain Rafi
- Department of Chemistry, American University, Washington, DC 20016, United States of America
- Center for Neuroscience and Behavior, American University, Washington, DC 20016, United States of America
| | - Alexander G. Zestos
- Department of Chemistry, American University, Washington, DC 20016, United States of America
- Center for Neuroscience and Behavior, American University, Washington, DC 20016, United States of America
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24
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Hejazi M, Tong W, Ibbotson MR, Prawer S, Garrett DJ. Advances in Carbon-Based Microfiber Electrodes for Neural Interfacing. Front Neurosci 2021; 15:658703. [PMID: 33912007 PMCID: PMC8072048 DOI: 10.3389/fnins.2021.658703] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/22/2021] [Indexed: 12/20/2022] Open
Abstract
Neural interfacing devices using penetrating microelectrode arrays have emerged as an important tool in both neuroscience research and medical applications. These implantable microelectrode arrays enable communication between man-made devices and the nervous system by detecting and/or evoking neuronal activities. Recent years have seen rapid development of electrodes fabricated using flexible, ultrathin carbon-based microfibers. Compared to electrodes fabricated using rigid materials and larger cross-sections, these microfiber electrodes have been shown to reduce foreign body responses after implantation, with improved signal-to-noise ratio for neural recording and enhanced resolution for neural stimulation. Here, we review recent progress of carbon-based microfiber electrodes in terms of material composition and fabrication technology. The remaining challenges and future directions for development of these arrays will also be discussed. Overall, these microfiber electrodes are expected to improve the longevity and reliability of neural interfacing devices.
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Affiliation(s)
- Maryam Hejazi
- School of Physics, The University of Melbourne, Parkville, VIC, Australia
| | - Wei Tong
- School of Physics, The University of Melbourne, Parkville, VIC, Australia
- National Vision Research Institute, The Australian College of Optometry, Carlton, VIC, Australia
| | - Michael R. Ibbotson
- National Vision Research Institute, The Australian College of Optometry, Carlton, VIC, Australia
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Steven Prawer
- School of Physics, The University of Melbourne, Parkville, VIC, Australia
| | - David J. Garrett
- School of Physics, The University of Melbourne, Parkville, VIC, Australia
- School of Engineering, RMIT University, Melbourne, VIC, Australia
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25
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Asrat T, Cho W, Liu FA, Shapiro SM, Bracht JR, Zestos AG. Direct Detection of DNA and RNA on Carbon Fiber Microelectrodes Using Fast-Scan Cyclic Voltammetry. ACS OMEGA 2021; 6:6571-6581. [PMID: 33748569 PMCID: PMC7970473 DOI: 10.1021/acsomega.0c04845] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 02/18/2021] [Indexed: 05/04/2023]
Abstract
DNA and RNA have been measured with many techniques but often with relatively long analysis times. In this study, we utilize fast-scan cyclic voltammetry (FSCV) for the subsecond codetection of adenine, guanine, and cytosine, first as free nucleosides, and then within custom synthesized oligos, plasmid DNA, and RNA from the nematode Caenorhabditis elegans. Previous studies have shown the detection of adenosine and guanosine with FSCV with high spatiotemporal resolution, while we have extended the assay to include cytidine and adenine, guanine, and cytosine in RNA and single- and double-stranded DNA (ssDNA and dSDNA). We find that FSCV testing has a higher sensitivity and yields higher peak oxidative currents when detecting shorter oligonucleotides and ssDNA samples at equivalent nucleobase concentrations. This is consistent with an electrostatic repulsion from negatively charged oxide groups on the surface of the carbon fiber microelectrode (CFME), the negative holding potential, and the negatively charged phosphate backbone. Moreover, as opposed to dsDNA, ssDNA nucleobases are not hydrogen-bonded to one another and thus are free to adsorb onto the surface of the carbon electrode. We also demonstrate that the simultaneous determination of nucleobases is not masked even in biologically complex serum samples. This is the first report demonstrating that FSCV, when used with CFMEs, is able to codetect nucleobases when polymerized into DNA or RNA and could potentially pave the way for future uses in clinical, diagnostic, or research applications.
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Affiliation(s)
- Thomas
M. Asrat
- Department
of Chemistry, American University, Washington, D.C. 20016, United States
| | - Whirang Cho
- Department
of Chemistry, American University, Washington, D.C. 20016, United States
| | - Favian A. Liu
- Department
of Chemistry, American University, Washington, D.C. 20016, United States
| | - Sarah M. Shapiro
- Department
of Biology, American University, Washington, D.C. 20016, United States
| | - John R. Bracht
- Department
of Biology, American University, Washington, D.C. 20016, United States
| | - Alexander G. Zestos
- Department
of Chemistry, American University, Washington, D.C. 20016, United States
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26
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Cao Q, Shao Z, Hensley DK, Lavrik NV, Venton BJ. Influence of Geometry on Thin Layer and Diffusion Processes at Carbon Electrodes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:2667-2676. [PMID: 33591763 PMCID: PMC7937503 DOI: 10.1021/acs.langmuir.0c03315] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The geometric structure of carbon electrodes affects their electrochemical behavior, and large-scale surface roughness leads to thin layer electrochemistry when analyte is trapped in pores. However, the current response is always a mixture of both thin layer and diffusion processes. Here, we systematically explore the effects of thin layer electrochemistry and diffusion at carbon fiber (CF), carbon nanospike (CNS), and carbon nanotube yarn (CNTY) electrodes. The cyclic voltammetry (CV) response to the surface-insensitive redox couple Ru(NH3)63+/2+ is tested, so the geometric structure is the only factor. At CFs, the reaction is diffusion-controlled because the surface is smooth. CNTY electrodes have gaps between nanotubes that are about 10 μm deep, comparable with the diffusion layer thickness. CNTY electrodes show clear thin layer behavior due to trapping effects, with more symmetrical peaks and ΔEp closer to zero. CNS electrodes have submicrometer scale roughness, so their CV shape is mostly due to diffusion, not thin layer effects. However, even the 10% contribution of thin layer behavior reduces the peak separation by 30 mV, indicating ΔEp is influenced not only by electron transfer kinetics but also by surface geometry. A new simulation model is developed to quantitate the thin layer and diffusion contributions that explains the CV shape and peak separation for CNS and CNTY electrodes, providing insight on the impact of scan rate and surface structure size. Thus, this study provides key understanding of thin layer and diffusion processes at different surface structures and will enable rational design of electrodes with thin layer electrochemistry.
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Affiliation(s)
- Qun Cao
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Zijun Shao
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Dale K. Hensley
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Nickolay V. Lavrik
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - B. Jill Venton
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
- Corresponding Author: B. Jill Venton,
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27
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Wonnenberg P, Cho W, Liu F, Asrat T, Zestos AG. Polymer Modified Carbon Fiber Microelectrodes for Precision Neurotransmitter Metabolite Measurements. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2020; 167:167507. [PMID: 33927450 PMCID: PMC8081299 DOI: 10.1149/1945-7111/abcb6d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Carbon fiber-microelectrodes (CFMEs) are considered to be one of the standard electrodes for neurotransmitter detection such as dopamine (DA). DA is physiologically important for many pharmacological and behavioral states, but is readily metabolized on a fast, subsecond timescale. Recently, DA metabolites such as 3-methoxytyramine (3-MT) and 3,4-dihydroxyphenylacetaldehyde (DOPAL) were found to be involved in physiological functions, such as movement control and progressive neuro degeneration. However, there is no current assay to detect and differentiate them from DA. In this study, we demonstrate the co-detection of similarly structured neurochemicals such as DA, 3-MT, and DOPAL. We accomplished this through electrodepositing CFMEs with polyethyleneimine (PEI) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymers. This endowed the bare unmodified CFMEs with surface charge, physical, and chemical differences, which resulted in the improved sensitivity and selectivity of neurotransmitter detection. The differentiation and detection of 3-MT, DOPAL, and DA will potentially help further understand the important physiological roles that these dopaminergic metabolites play in vivo.
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Affiliation(s)
- Pauline Wonnenberg
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Whirang Cho
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Favian Liu
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Thomas Asrat
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Alexander G. Zestos
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
- Center for Behavioral Neuroscience, American University, Washington, D.C. 20016, United States of America
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28
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Shao Z, Puthongkham P, Hu K, Jia R, Mirkin MV, Venton BJ. Thin layer cell behavior of CNT yarn and cavity carbon nanopipette electrodes: Effect on catecholamine detection. Electrochim Acta 2020; 361. [PMID: 32981947 DOI: 10.1016/j.electacta.2020.137032] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Carbon nanotube yarn microelectrodes (CNTYMEs) are an alternative to carbon-fiber microelectrodes (CFMEs) with interesting electrochemical properties because analyte is momentarily trapped in cavities between the CNTs. Here, we compare fast-scan cyclic voltammetry (FSCV) detection of catecholamines, including dopamine, norepinephrine, and epinephrine, at CNTYMEs, CFMEs, as well as cavity carbon nanopipette electrodes (CNPEs). At CFMEs, current decreases dramatically at high FSCV repetition frequencies. At CNTYMEs, current is almost independent of FSCV repetition frequency because the analytes are trapped in the crevices between CNTs, and thus the electrode acts like a thin-layer cell. At CFMEs, small cyclization product peaks are observed due to an intramolecular cyclization reaction to form leucocatecholamine, which is electroactive, and these peaks are largest for the secondary amine epinephrine. At CNTYMEs, more of the leucocatecholamine cyclization product is detected for all catecholamines because of the enhanced trapping effects, particularly at higher repetition rates where the reaction occurs more frequently and more product is accumulated. For epinephrine, the secondary peaks have larger currents than the primary oxidation peaks at 100 Hz, and similar trends are observed with faster scan rates and 500 Hz repetition frequencies. Finally, we examined CNPEs, which also momentarily trap neurotransmitters. Similar to CNTYMEs, at CNPEs, catecholamines have robust cyclization peaks, particularly at high repetition rates. Thus, CNTYMEs and CNPEs have thin layer cell behavior that facilitates high temporal resolution measurements, but catecholamines CVs are complicated by cyclization reactions. However, those additional peaks could be useful in discriminating the analytes, particularly epinephrine and norepinephrine.
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Affiliation(s)
- Zijun Shao
- Dept. of Chemistry, University of Virginia, Charlottesville, VA 22901
| | | | - KeKe Hu
- Department of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367 and Graduate Center of CUNY, New York, NY 10016, USA
| | - Rui Jia
- Department of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367 and Graduate Center of CUNY, New York, NY 10016, USA
| | - Michael V Mirkin
- Department of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367 and Graduate Center of CUNY, New York, NY 10016, USA
| | - B Jill Venton
- Dept. of Chemistry, University of Virginia, Charlottesville, VA 22901
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29
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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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30
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Cho W, Liu F, Hendrix A, McCray B, Asrat T, Connaughton V, Zestos AG. Timed Electrodeposition of PEDOT:Nafion onto Carbon Fiber-Microelectrodes Enhances Dopamine Detection in Zebrafish Retina. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2020; 167:115501. [PMID: 33927449 PMCID: PMC8081298 DOI: 10.1149/1945-7111/aba33d] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Carbon fiber-microelectrodes (CFMEs) are one of the standards for the detection of neurotransmitters such as dopamine (DA). In this study, we demonstrate that CFMEs electrodeposited with poly (3,4-ethylenedioxythiophene) (PEDOT) in the presence of Nafion exhibit enhanced sensitivity for DA detection. Scanning electron microscopy (SEM) revealed the smooth outer surface morphologies of polymer coatings, which filled in the ridges and grooves of the bare unmodified carbon electrode and energy-dispersive X-ray spectroscopy (EDX) confirmed PEDOT:Nafion incorporation. PEDOT:Nafion coated CMFEs exhibited a statistically enhanced two-fold increase in DA sensitivity compared to unmodified microelectrodes, with stability and integrity of the coated microelectrodes maintained for at least 4 h. A scan rate test revealed a linear relationship with peak DA oxidative current (5 μM), indicating adsorption control of DA to the surface of the PEDOT:Nafion electrode. As proof of principle, PEDOT:Nafion coated electrodes were used to detect potassium chloride (KCl)-induced DA release in zebrafish (Danio rerio) retinal tissue ex vivo, thus illustrating their applicability as biosensors.
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Affiliation(s)
- Whirang Cho
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Favian Liu
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Aaron Hendrix
- Department of Biology, American University, Washington, D.C. 20016, United States of America
| | - Brazil McCray
- Department of Biology, American University, Washington, D.C. 20016, United States of America
| | - Thomas Asrat
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
| | - Victoria Connaughton
- Department of Biology, American University, Washington, D.C. 20016, United States of America
- Center for Behavioral Neuroscience, American University, Washington, D.C. 20016, United States of America
| | - Alexander G. Zestos
- Department of Chemistry, American University, Washington, D.C. 20016, United States of America
- Center for Behavioral Neuroscience, American University, Washington, D.C. 20016, United States of America
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31
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Chang Y, Venton BJ. Optimization of graphene oxide-modified carbon-fiber microelectrode for dopamine detection. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:2893-2902. [PMID: 32617123 PMCID: PMC7331934 DOI: 10.1039/d0ay00310g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Graphene oxide (GO) is a carbon-based material that is easily obtained from graphite or graphite oxide. GO has been used broadly for electrochemistry applications and our hypothesis is that GO coating a carbon-fiber microelectrode (CFME) will increase the sensitivity for dopamine by providing more adsorption sites due to the enhancement of oxygen functional groups. Here, we compared drop casting, dip coating, and electrodeposition methods to directly coat commercial GO on CFME surfaces. Dip coating did not result in much GO coating and drop casting resulted in large agglomerations that produced noisy signals and slow rise times. Electrodeposition method with cyclic voltammetry increase the current for dopamine and this method was the most reproducible and had the least noise compared to the other two coating methods. The optimized method used a triangular waveform scanned from -1.2 V to 1.5 V at 100 mV/s for 5 cycles in 0.2 mg/mL GO in water. With fast-scan cyclic voltammetry (FSCV), the optimized GO/CFME enhanced the dopamine oxidation peak two-fold. The sensitivity of the modified electrode is 41±2 nA/μM with a linear range from 25 nM to 1 μM, and a limit of detection of 11 nM. The optimized electrodes were used to detect electrically-stimulated dopamine in brain slices to demonstrate their performance in tissue. Thus, GO can be used to enhance the sensitivity of electrodes for dopamine and improve biological measurements.
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Affiliation(s)
- Yuanyu Chang
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, United States
| | - B Jill Venton
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, United States
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32
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Gupta P, Tsai K, Ruhunage CK, Gupta VK, Rahm CE, Jiang D, Alvarez NT. True Picomolar Neurotransmitter Sensor Based on Open-Ended Carbon Nanotubes. Anal Chem 2020; 92:8536-8545. [PMID: 32406234 DOI: 10.1021/acs.analchem.0c01363] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Neurotransmitters are important chemicals in human physiological systems for initiating neuronal signaling pathways and in various critical health illnesses. However, concentration of neurotransmitters in the human body is very low (nM or pM level) and it is extremely difficult to detect the fluctuation of their concentrations in patients using existing electrochemical biosensors. In this work, we report the performance of highly densified carbon nanotubes fiber (HD-CNTf) cross-sections called rods (diameter ∼ 69 μm, and length ∼ 40 μm) as an ultrasensitive platform for detection of common neurotransmitters. HD-CNTf rods microelectrodes have open-ended CNTs exposed at the interface with electrolytes and cells and display a low impedance value, i.e., 1050 Ω. Their fabrication starts with dry spun CNT fibers that are encapsulated in an insulating polymer to preserve their structure and alignment. Arrays of HD-CNTf rods microelectrodes were applied to detect neurotransmitters, i.e., dopamine (DA), serotonin (5-HT), epinephrine (Epn), and norepinephrine (Norepn), using square wave voltammetry (SWV) and cyclic voltammetry (CV). They demonstrate good linearity in a broad linear range (1 nM to 100 μM) with an excellent limit of detection, i.e., 32 pM, 31 pM, 64 pM, and 9 pM for DA, 5-HT, Epn, and Norepn, respectively. To demonstrate practical application of HD-CNTf rod arrays, detection of DA in human biological fluids and real time monitoring of DA release from living pheochromocytoma (PC12) cells were performed.
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Affiliation(s)
- Pankaj Gupta
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Kyrus Tsai
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Chethani K Ruhunage
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Vandna K Gupta
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Connor E Rahm
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Dehua Jiang
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Noe T Alvarez
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
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33
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Wonnenberg PM, Zestos AG. Polymer-Modified Carbon Fiber Microelectrodes for Neurochemical Detection of Dopamine and Metabolites. ECS TRANSACTIONS 2020; 97:901-927. [PMID: 33953827 PMCID: PMC8096166 DOI: 10.1149/09707.0901ecst] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Carbon-fiber microelectrodes (CFMEs) are considered to be the standard electrodes for neurotransmitter detection. Fast-scan cyclic voltammetry (FSCV), an electro analytical method, has the ability to follow neurochemical dynamics in real time using CFMEs. Improvements in neurochemical detection with CFMEs were previously made through the coating of polymers onto the surface of the carbon-fiber. Polymers such as PEI, PEDOT, and Nafion were electrodeposited onto the surface of the electrodes to enhance neurochemical detection. This work demonstrates applications for enhancements in co-detection of similarly structured neurochemicals such as dopamine, DOPAL, 3-methoxytyramine, DOPAC, and other neurotransmitters. Manipulating the charge and surface structure of the carbon electrode allows for the improvement of sensitivity and selectivity of neurotransmitter detection. The analytes are detected and differentiated by the shape and the peak positions of their respective cyclic voltammograms.
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Affiliation(s)
- P M Wonnenberg
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, District of Columbia 20016, USA
| | - A G Zestos
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, District of Columbia 20016, USA
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34
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Adhikari J, Rizwan M, Keasberry NA, Ahmed MU. Current progresses and trends in carbon nanomaterials‐based electrochemical and electrochemiluminescence biosensors. J CHIN CHEM SOC-TAIP 2020. [DOI: 10.1002/jccs.201900417] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Juthi Adhikari
- Biosensors and Nanobiotechnology Laboratory, Chemical Science Programme, Faculty of ScienceUniversiti Brunei Darussalam Gadong Brunei Darussalam
| | - Mohammad Rizwan
- Biosensors and Nanobiotechnology Laboratory, Chemical Science Programme, Faculty of ScienceUniversiti Brunei Darussalam Gadong Brunei Darussalam
- School of Natural SciencesBangor University Bangor Wales UK
| | - Natasha Ann Keasberry
- Biosensors and Nanobiotechnology Laboratory, Chemical Science Programme, Faculty of ScienceUniversiti Brunei Darussalam Gadong Brunei Darussalam
| | - Minhaz Uddin Ahmed
- Biosensors and Nanobiotechnology Laboratory, Chemical Science Programme, Faculty of ScienceUniversiti Brunei Darussalam Gadong Brunei Darussalam
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35
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Castagnola E, Woeppel K, Golabchi A, McGuier M, Chodapaneedi N, Metro J, Taylor IM, Cui XT. Electrochemical detection of exogenously administered melatonin in the brain. Analyst 2020; 145:2612-2620. [PMID: 32073100 PMCID: PMC7236429 DOI: 10.1039/d0an00051e] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Melatonin (MT) is an important electroactive hormone that regulates different physiological actions in the brain, ranging from circadian clock to neurodegeneration. An impressive number of publications have highlighted the effectiveness of MT treatments in different types of sleep and neurological disorders, including Alzheimer's and Parkinson's disease. The ability to detect MT in different regions of the brain would provide further insights into the physiological roles and therapeutic effects of MT. While multiple electrochemical methods have been used to detect MT in biological samples, monitoring MT in the brain of live animals has not been demonstrated. Here, we optimized a square wave voltammetry (SWV) electroanalytical method to evaluate the MT detection performance at CFEs in vitro and in vivo. SWV was able to sensitively detect the MT oxidation peak at 0.7 V, and discriminate MT from most common interferents in vitro. More importantly, using the optimized SWV, CFEs successfully detected and reliably quantified MT concentrations in the visual cortex of anesthetized mice after intraperitoneal injections of different MT doses, offering stable MT signals for up to 40 minutes. To the best of our knowledge, this is the first electrochemical measurement of exogenously administered MT in vivo. This electrochemical MT sensing technique will provide a powerful tool for further understanding MT's action in the brain.
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Affiliation(s)
- Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
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36
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Mendoza A, Asrat T, Liu F, Wonnenberg P, Zestos AG. Carbon Nanotube Yarn Microelectrodes Promote High Temporal Measurements of Serotonin Using Fast Scan Cyclic Voltammetry. SENSORS (BASEL, SWITZERLAND) 2020; 20:E1173. [PMID: 32093345 PMCID: PMC7070315 DOI: 10.3390/s20041173] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 12/11/2022]
Abstract
Carbon fiber-microelectrodes (CFMEs) have been the standard for neurotransmitter detection for over forty years. However, in recent years, there have been many advances of utilizing alternative nanomaterials for neurotransmitter detection with fast scan cyclic voltammetry (FSCV). Recently, carbon nanotube (CNT) yarns have been developed as the working electrode materials for neurotransmitter sensing capabilities with fast scan cyclic voltammetry. Carbon nanotubes are ideal for neurotransmitter detection because they have higher aspect ratios enabling monoamine adsorption and lower limits of detection, faster electron transfer kinetics, and a resistance to surface fouling. Several methods to modify CFMEs with CNTs have resulted in increases in sensitivity, but have also increased noise and led to irreproducible results. In this study, we utilize commercially available CNT-yarns to make microelectrodes as enhanced neurotransmitter sensors for neurotransmitters such as serotonin. CNT-yarn microelectrodes have significantly higher sensitivities (peak oxidative currents of the cyclic voltammograms) than CFMEs and faster electron transfer kinetics as measured by peak separation (ΔEP) values. Moreover, both serotonin and dopamine are adsorption controlled to the surface of the electrode as measured by scan rate and concentration experiments. CNT yarn microelectrodes also resisted surface fouling of serotonin onto the surface of the electrode over thirty minutes and had a wave application frequency independent response to sensitivity at the surface of the electrode.
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Affiliation(s)
| | | | | | | | - Alexander G. Zestos
- Department of Chemistry and Center for Behavioral Neuroscience, American University, Washington, DC 20016, USA; (A.M.); (T.A.); (F.L.); (P.W.)
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37
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A microfluidic electrochemical flow cell capable of rapid on-chip dilution for fast-scan cyclic voltammetry electrode calibration. Anal Bioanal Chem 2020; 412:6287-6294. [PMID: 32064570 DOI: 10.1007/s00216-020-02493-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/13/2020] [Accepted: 02/05/2020] [Indexed: 10/25/2022]
Abstract
Here, we developed a microfluidic electrochemical flow cell for fast-scan cyclic voltammetry which is capable of rapid on-chip dilution for efficient and cost-effective electrode calibration. Fast-scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes is a robust electroanalytical technique used to measure subsecond changes in neurotransmitter concentration over time. Traditional methods of electrode calibration for FSCV require several milliliters of a standard. Additionally, generating calibration curves can be time-consuming because separate solutions must be prepared for each concentration. Microfluidic electrochemical flow cells have been developed in the past; however, they often require incorporating the electrode in the device, making it difficult to remove for testing in biological tissues. Likewise, current microfluidic electrochemical flow cells are not capable of rapid on-chip dilution to eliminate the requirement of making multiple solutions. We designed a T-channel device, with microchannel dimensions of 100 μm × 50 μm, that delivered a standard to a 2-mm-diameter open electrode sampling well. A waste channel with the same dimensions was designed perpendicular to the well to flush and remove the standard. The dimensions of the T-microchannels and flow rates were chosen to facilitate complete mixing in the delivery channel prior to reaching the electrode. The degree of mixing was computationally modeled using COMSOL and was quantitatively assessed in the device using both colored dyes and electrochemical detection. On-chip electrode calibration for dopamine with FSCV was not significantly different than the traditional calibration method demonstrating its utility for FSCV calibration. Overall, this device improves the efficiency and ease of electrode calibration. Graphical abstract.
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38
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Abstract
Fast-scan cyclic voltammetry (FSCV) is used with carbon-fiber microelectrodes for the real-time detection of neurotransmitters on the subsecond time scale. With FSCV, the potential is ramped up from a holding potential to a switching potential and back, usually at a 400 V s-1 scan rate and a frequency of 10 Hz. The plot of current vs. applied potential, the cyclic voltammogram (CV), has a very different shape for FSCV than for traditional cyclic voltammetry collected at scan rates which are 1000-fold slower. Here, we explore the theory of FSCV, with a focus on dopamine detection. First, we examine the shape of the CVs. Background currents, which are 100-fold higher than faradaic currents, are subtracted out. Peak separation is primarily due to slow electron transfer kinetics, while the symmetrical peak shape is due to exhaustive electrolysis of all the adsorbed neurotransmitters. Second, we explain the origins of the dopamine waveform, and the factors that limit the holding potential (oxygen reduction), switching potential (water oxidation), scan rate (electrode instability), and repetition rate (adsorption). Third, we discuss data analysis, from data visualization with color plots, to the automated algorithms like principal components regression that distinguish dopamine from pH changes. Finally, newer applications are discussed, including optimization of waveforms for analyte selectivity, carbon nanomaterial electrodes that trap dopamine, and basal level measurements that facilitate neurotransmitter measurements on a longer time scale. FSCV theory is complex, but understanding it enables better development of new techniques to monitor neurotransmitters in vivo.
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Affiliation(s)
- B Jill Venton
- Dept. of Chemistry, University of Virginia, PO Box 400319, Charlottesville, VA 22901, USA.
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Abstract
Fast-scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes (CFMEs) is a versatile electrochemical technique to probe neurochemical dynamics in vivo. Progress in FSCV methodology continues to address analytical challenges arising from biological needs to measure low concentrations of neurotransmitters at specific sites. This review summarizes recent advances in FSCV method development in three areas: (1) waveform optimization, (2) electrode development, and (3) data analysis. First, FSCV waveform parameters such as holding potential, switching potential, and scan rate have been optimized to monitor new neurochemicals. The new waveform shapes introduce better selectivity toward specific molecules such as serotonin, histamine, hydrogen peroxide, octopamine, adenosine, guanosine, and neuropeptides. Second, CFMEs have been modified with nanomaterials such as carbon nanotubes or replaced with conducting polymers to enhance sensitivity, selectivity, and antifouling properties. Different geometries can be obtained by 3D-printing, manufacturing arrays, or fabricating carbon nanopipettes. Third, data analysis is important to sort through the thousands of CVs obtained. Recent developments in data analysis include preprocessing by digital filtering, principal components analysis for distinguishing analytes, and developing automated algorithms to detect peaks. Future challenges include multisite measurements, machine learning, and integration with other techniques. Advances in FSCV will accelerate research in neurochemistry to answer new biological questions about dynamics of signaling in the brain.
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Affiliation(s)
- Pumidech Puthongkham
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
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Jang Y, Kim SM, Spinks GM, Kim SJ. Carbon Nanotube Yarn for Fiber-Shaped Electrical Sensors, Actuators, and Energy Storage for Smart Systems. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1902670. [PMID: 31403227 DOI: 10.1002/adma.201902670] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/18/2019] [Indexed: 06/10/2023]
Abstract
Smart systems are those that display autonomous or collaborative functionalities, and include the ability to sense multiple inputs, to respond with appropriate operations, and to control a given situation. In certain circumstances, it is also of great interest to retain flexible, stretchable, portable, wearable, and/or implantable attributes in smart electronic systems. Among the promising candidate smart materials, carbon nanotubes (CNTs) exhibit excellent electrical and mechanical properties, and structurally fabricated CNT-based fibers and yarns with coil and twist further introduce flexible and stretchable properties. A number of notable studies have demonstrated various functions of CNT yarns, including sensors, actuators, and energy storage. In particular, CNT yarns can operate as flexible electronic sensors and electrodes to monitor strain, temperature, ionic concentration, and the concentration of target biomolecules. Moreover, a twisted CNT yarn enables strong torsional actuation, and coiled CNT yarns generate large tensile strokes as an artificial muscle. Furthermore, the reversible actuation of CNT yarns can be used as an energy harvester and, when combined with a CNT supercapacitor, has promoted the next-generation of energy storage systems. Here, progressive advances of CNT yarns in electrical sensing, actuation, and energy storage are reported, and the future challenges in smart electronic systems considered.
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Affiliation(s)
- Yongwoo Jang
- Center for Self-Powered Actuation, Department of Biomedical Engineering, Hanyang University, Seoul, 04763, South Korea
| | - Sung Min Kim
- Department of Physical Education, Department of Active Aging Industry, Hanyang University, Seoul, 04763, South Korea
| | - Geoffrey M Spinks
- Australian Institute for Innovative Materials, ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Seon Jeong Kim
- Center for Self-Powered Actuation, Department of Biomedical Engineering, Hanyang University, Seoul, 04763, South Korea
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Cao Q, Hensley DK, Lavrik NV, Venton BJ. Carbon nanospikes have better electrochemical properties than carbon nanotubes due to greater surface roughness and defect sites. CARBON 2019; 155:250-257. [PMID: 31588146 PMCID: PMC6777722 DOI: 10.1016/j.carbon.2019.08.064] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Carbon nanomaterials are used to improve electrodes for neurotransmitter detection, but what properties are important for maximizing those effects? In this work, we compare a newer form of graphene, carbon nanospikes (CNSs), with carbon nanotubes (CNTs) grown on wires and carbon fibers (CFs). CNS electrodes have a short, dense, defect-filled surface that produces remarkable electrochemical properties, much better than CNTs or CFs. The CNS surface roughness is 5.5 times greater than glassy carbon, while CNTs enhance roughness only 1.8-fold. D/G ratios are higher for CNS electrodes than CNT electrodes, an indication of more defect sites. For cyclic voltammetry of dopamine and ferricyanide, CNSs have both higher currents and smaller ΔEp values than CNTs and CFs. CNS electrodes also have a very low resistance to charge transfer. With fast-scan cyclic voltammetry (FSCV), CNS electrodes have enhanced current density for dopamine and cationic neurotransmitters due to increased adsorption to edge plane sites. This study establishes that not all carbon nanomaterials are equally advantageous for dopamine electrochemistry, but that short, dense nanomaterials that add defect sites provide improved current and electron transfer. CNSs are simple to mass fabricate on a variety of substrates and thus could be a favorable material for neurotransmitter sensing.
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Affiliation(s)
- Qun Cao
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - Dale K. Hensley
- Center for Nanophase Material Science, Oak Ridge National Lab, Oak Ridge, TN 37831
| | - Nickolay V. Lavrik
- Center for Nanophase Material Science, Oak Ridge National Lab, Oak Ridge, TN 37831
| | - B. Jill Venton
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
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Mohanaraj S, Wonnenberg P, Cohen B, Zhao H, Hartings MR, Zou S, Fox DM, Zestos AG. Gold Nanoparticle Modified Carbon Fiber Microelectrodes for Enhanced Neurochemical Detection. J Vis Exp 2019:10.3791/59552. [PMID: 31132067 PMCID: PMC8266205 DOI: 10.3791/59552] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
For over 30 years, carbon-fiber microelectrodes (CFMEs) have been the standard for neurotransmitter detection. Generally, carbon fibers are aspirated into glass capillaries, pulled to a fine taper, and then sealed using an epoxy to create electrode materials that are used for fast scan cyclic voltammetry testing. The use of bare CFMEs has several limitations, though. First and foremost, the carbon fiber contains mostly basal plane carbon, which has a relatively low surface area and yields lower sensitivities than other nanomaterials. Furthermore, the graphitic carbon is limited by its temporal resolution, and its relatively low conductivity. Lastly, neurochemicals and macromolecules have been known to foul at the surface of carbon electrodes where they form non-conductive polymers that block further neurotransmitter adsorption. For this study, we modify CFMEs with gold nanoparticles to enhance neurochemical testing with fast scan cyclic voltammetry. Au3+ was electrodeposited or dipcoated from a colloidal solution onto the surface of CFMEs. Since gold is a stable and relatively inert metal, it is an ideal electrode material for analytical measurements of neurochemicals. Gold nanoparticle modified (AuNP-CFMEs) had a stability to dopamine response for over 4 h. Moreover, AuNP-CFMEs exhibit an increased sensitivity (higher peak oxidative current of the cyclic voltammograms) and faster electron transfer kinetics (lower ΔEP or peak separation) than bare unmodified CFMEs. The development of AuNP-CFMEs provides the creation of novel electrochemical sensors for detecting fast changes in dopamine concentration and other neurochemicals at lower limits of detection. This work has vast applications for the enhancement of neurochemical measurements. The generation of gold nanoparticle modified CFMEs will be vitally important for the development of novel electrode sensors to detect neurotransmitters in vivo in rodent and other models to study neurochemical effects of drug abuse, depression, stroke, ischemia, and other behavioral and disease states.
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Affiliation(s)
| | | | | | - He Zhao
- Department of Chemistry, American University
| | | | | | | | - Alexander G Zestos
- Department of Chemistry, American University; Center for Behavioral Neuroscience, American University;
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Weese ME, Krevh RA, Li Y, Alvarez NT, Ross AE. Defect Sites Modulate Fouling Resistance on Carbon-Nanotube Fiber Electrodes. ACS Sens 2019; 4:1001-1007. [PMID: 30920207 DOI: 10.1021/acssensors.9b00161] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Carbon nanotube (CNT) fiber electrodes have become increasingly popular electrode materials for neurotransmitter detection with fast-scan cyclic voltammetry (FSCV). The unique properties of CNT fiber electrodes like increased electron transfer, sensitivity, waveform application frequency independence, and resistance to fouling make them ideal biological sensors for FSCV. In particular, their resistance to fouling has been observed for several years, but the specific physical properties which aid in fouling resistance have been debated. Here, we investigate the extent to which the presence of defect sites on the surface attenuate both chemical and biological fouling with FSCV. We compared traditional carbon-fiber microelectrodes (CFMEs) to pristine CNTs and functionalized CNTs. CFMEs and functionalized CNTs are highly disordered with a great deal of defect sites on the surface. The pristine CNTs have fewer defects compared to the purposefully functionalized CNTs and CFMEs. All electrode surfaces were characterized by a combination of scanning electron microscopy (SEM), Raman spectroscopy, and energy dispersive spectroscopy (EDS). Chemical fouling was studied using serotonin, a popular neurotransmitter notoriously known for electrode fouling. To assess biological fouling, electrodes were implanted in brain tissue for 2 h. Defect sites on the carbon were shown to resist biofouling compared to pristine CNTs but were detrimental for serotonin detection. Overall, we provide insight into the extent to which the electrode surface dictates fouling resistance with FSCV. This work provides evidence that careful considerations of the surface of the CNT material are needed when designing sensors for fouling resistance.
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Affiliation(s)
- Moriah E. Weese
- Department of Chemistry, University of Cincinnati, 404 Crosley Tower, 312 College Dr., Cincinnati, Ohio 45221-0172, United States
| | - Rachel A. Krevh
- Department of Chemistry, University of Cincinnati, 404 Crosley Tower, 312 College Dr., Cincinnati, Ohio 45221-0172, United States
| | - Yuxin Li
- Department of Chemistry, University of Cincinnati, 404 Crosley Tower, 312 College Dr., Cincinnati, Ohio 45221-0172, United States
| | - Noe T. Alvarez
- Department of Chemistry, University of Cincinnati, 404 Crosley Tower, 312 College Dr., Cincinnati, Ohio 45221-0172, United States
| | - Ashley E. Ross
- Department of Chemistry, University of Cincinnati, 404 Crosley Tower, 312 College Dr., Cincinnati, Ohio 45221-0172, United States
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Raju D, Mendoza A, Wonnenberg P, Mohanaraj S, Sarbanes M, Truong C, Zestos AG. Polymer Modified Carbon Fiber-Microelectrodes and Waveform Modifications Enhance Neurotransmitter Metabolite Detection. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2019; 11:1620-1630. [PMID: 34079589 PMCID: PMC8168831 DOI: 10.1039/c8ay02737d] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Carbon-fiber microelectrodes (CFMEs) have been used for several years for the detection of neurotransmitters such as dopamine. Dopamine is a fundamentally important neurotransmitter and is also metabolized at a subsecond timescale. Recently, several metabolites of dopamine have been shown to be physiologically important such as 3-methoxytyramine (3-MT), 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA). Many of these neurotransmitter metabolites are currently only detected with microdialysis coupled with liquid chromatography with relatively low temporal and spatial resolution. Current electrochemical methods such as the dopamine waveform (scanning from -0.4 to 1.3 V at 400 V/sec) are utilized to electrostatically repel anions such as DOPAC and promote dopamine adsorption to the surface of the electrode. Moreover, polymer coatings such as Nafion have been shown to electrostatically repel anions such as 5-hydroxyindoleacetic acid (5-HIAA). In this study, we develop novel polymer and waveform modifications for enhanced DOPAC detection. Applying the DOPAC waveform (scanning from 0 to 1.3 V at 400 V/sec) enhances DOPAC detection significantly because it does not include the negative holding potential of the dopamine waveform. Moreover, positively charged cationic polymers such as polyethyleneimine (PEI) allow for the preconcentration of DOPAC to the surface of the carbon fiber through an electrostatic attraction. The limit of detection for DOPAC for PEI coated CFMEs with the DOPAC waveform applied is 58.2 ± 2 nM as opposed to 291 ± 10 nM for unmodified electrodes applying the dopamine waveform (n = 4). This work offers promise for the development of novel electrode materials and waveforms for the specific detection of several important biomolecules such as dopamine metabolite neurotransmitters.
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Affiliation(s)
- Dilpreet Raju
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
| | - Alexander Mendoza
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
| | - Pauline Wonnenberg
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
| | - Sanuja Mohanaraj
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
| | - Mulugeta Sarbanes
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
| | - Carly Truong
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
| | - Alexander G Zestos
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016
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Lim GN, Ross AE. Purine Functional Group Type and Placement Modulate the Interaction with Carbon-Fiber Microelectrodes. ACS Sens 2019; 4:479-487. [PMID: 30657307 DOI: 10.1021/acssensors.8b01504] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Purine detection in the brain with fast-scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes (CFME) has become increasingly popular over the past decade; despite the growing interest, an in-depth analysis of how purines interact with the CFME at fast-scan rates has not been investigated. Here, we show how the functional group type and placement in the purine ring modulate sensitivity, electron transfer kinetics, and adsorption on the carbon-fiber surface. Similar investigations of catecholamine interaction at CFME with FSCV have informed the development of novel catecholamine-based sensors and is needed for purine-based sensors. We tested purine bases with either amino, carbonyl, or both functional groups substituted at different positions on the ring and an unsubstituted purine. Unsubstituted purine showed very little to no interaction with the electrode surface, indicating that functional groups are important for interaction at the CFME. Purine nucleosides and nucleotides, like adenosine, guanosine, and adenosine triphosphate, are most often probed using FSCV due to their rich extracellular signaling modalities in the brain. Because of this, the extent to which the ribose and triphosphate groups affect the purine-CFME interaction was also evaluated. Amino functional groups facilitated the interaction of purine analogues with CFME more than carbonyl groups, permitting strong adsorption and high surface coverage. Ribose and triphosphate groups decreased the oxidative current and slowed the interaction at the electrode which is likely due to steric effects and electrostatic repulsion. This work provides insight into the factors that affect purine-CFME interaction and conditions to consider when developing purine-targeted sensors for FSCV.
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Affiliation(s)
- Gary N. Lim
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Ashley E. Ross
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
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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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Barlow ST, Louie M, Hao R, Defnet PA, Zhang B. Electrodeposited Gold on Carbon-Fiber Microelectrodes for Enhancing Amperometric Detection of Dopamine Release from Pheochromocytoma Cells. Anal Chem 2018; 90:10049-10055. [PMID: 30047726 PMCID: PMC10879420 DOI: 10.1021/acs.analchem.8b02750] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Exocytosis is an ultrafast cellular process which facilitates neuron-neuron communication in the brain. Microelectrode electrochemistry has been an essential tool for measuring fast exocytosis events with high temporal resolution and high sensitivity. Due to carbon fiber's irreproducible and inhomogeneous surface conditions, however, it is often desirable to develop simple and reproducible modification schemes to enhance a microelectrode's analytical performance for single-cell analysis. Here we present carbon-fiber microelectrodes (CFEs) modified with a thin film of electrodeposited gold for the detection of exocytosis from rat pheochromocytoma cells (PC12), a model cell line for neurosecretion. These new probes are made by a novel voltage-pulsing deposition procedure and demonstrate improved electron-transfer characteristics for catecholamine oxidation, and their fabrication is tractable for many different probe designs. When we applied the probes to the detection of catecholamine release, we found that they outperformed unmodified CFEs. Further, the improved performance was conserved at cells incubated with L-DOPA (l-3,4-dihydroxyphenylalanine), a precursor to dopamine that increases the quantal size of the release events. Future use of this method may allow nanoelectrodes to be modified for highly sensitive detection of exocytosis from chemical synapses.
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Affiliation(s)
- Samuel T. Barlow
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Matthew Louie
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Rui Hao
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Peter A. Defnet
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Bo Zhang
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
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48
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Siddiqi KS, Husen A, Sohrab SS, Yassin MO. Recent Status of Nanomaterial Fabrication and Their Potential Applications in Neurological Disease Management. NANOSCALE RESEARCH LETTERS 2018; 13:231. [PMID: 30097809 PMCID: PMC6086777 DOI: 10.1186/s11671-018-2638-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/24/2018] [Indexed: 05/05/2023]
Abstract
Nanomaterials (NMs) are receiving remarkable attention due to their unique properties and structure. They vary from atoms and molecules along with those of bulk materials. They can be engineered to act as drug delivery vehicles to cross blood-brain barriers (BBBs) and utilized with better efficacy and safety to deliver specific molecules into targeted cells as compared to conventional system for neurological disorders. Depending on their properties, various metal chelators, gold nanoparticles (NPs), micelles, quantum dots, polymeric NPs, liposomes, solid lipid NPs, microparticles, carbon nanotubes, and fullerenes have been utilized for various purposes including the improvement of drug delivery system, treatment response assessment, diagnosis at early stage, and management of neurological disorder by using neuro-engineering. BBB regulates micro- and macromolecule penetration/movement, thus protecting it from many kinds of illness. This phenomenon also prevents drug delivery for the neurological disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis, amyotrophic lateral sclerosis, and primary brain tumors. For some neurological disorders (AD and PD), the environmental pollution was considered as a major cause, as observed that metal and/or metal oxide from different sources are inhaled and get deposited in the lungs/brain. Old age, obesity, diabetes, and cardiovascular disease are other factors for rapid deterioration of human health and onset of AD. In addition, gene mutations have also been examined to cause the early onset familial forms of AD. AD leads to cognitive impairment and plaque deposits in the brain leading to neuronal cell death. Based on these facts and considerations, this review elucidates the importance of frequently used metal chelators, NMs and/or NPs. The present review also discusses the current status and future challenges in terms of their application in drug delivery for neurological disease management.
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Affiliation(s)
| | - Azamal Husen
- Department of Biology, College of Natural and Computational Sciences, University of Gondar, PO Box # 196, Gondar, Ethiopia
| | - Sayed Sartaj Sohrab
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, PO Box # 80216, Jeddah, 21589 Saudi Arabia
| | - Mensur Osman Yassin
- Department of Surgery, College of Medicine and Health Sciences, University of Gondar, PO Box # 196, Gondar, Ethiopia
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Carbon Nanoelectrodes for the Electrochemical Detection of Neurotransmitters. INTERNATIONAL JOURNAL OF ELECTROCHEMISTRY 2018; 2018. [PMID: 34306762 PMCID: PMC8301601 DOI: 10.1155/2018/3679627] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Carbon-based electrodes have been developed for the detection of neurotransmitters over the past 30 years using voltammetry and amperometry. The traditional electrode for neurotransmitter detection is the carbon fiber microelectrode (CFME). The carbon-based electrode is suitable for in vivo neurotransmitter detection due to the fact that it is biocompatible and relatively small in surface area. The advent of nanoscale electrodes is in high demand due to smaller surface areas required to target specific brain regions that are also minimally invasive and cause relatively low tissue damage when implanted into living organisms. Carbon nanotubes (CNTs), carbon nanofibers, carbon nanospikes, and carbon nanopetals among others have all been utilized for this purpose. Novel electrode materials have also required novel insulations such as glass, epoxy, and polyimide coated fused silica capillaries for their construction and usage. Recent research developments have yielded a wide array of carbon nanoelectrodes with superior properties and performances in comparison to traditional electrode materials. These electrodes have thoroughly enhanced neurotransmitter detection allowing for the sensing of biological compounds at lower limits of detection, fast temporal resolution, and without surface fouling. This will allow for greater understanding of several neurological disease states based on the detection of neurotransmitters.
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50
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Zestos AG, Venton BJ. Communication-Carbon Nanotube Fiber Microelectrodes for High Temporal Measurements of Dopamine. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2018; 165:G3071-G3073. [PMID: 30197450 PMCID: PMC6121781 DOI: 10.1149/2.0111812jes] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Carbon nanotube (CNT) yarn and fiber-microelectrodes were developed for neurotransmitter detection using fast scan cyclic voltammetry (FSCV). Fibers were made by suspending CNTs in acid/surfactant and extruding into acetone/polyethyleneimine (PEI) and compared to a CNT yarn. They were FSCV frequency independent for dopamine up to 100 Hz. With faster frequencies, up to 500 Hz, high currents are maintained, which allows a 2 ms sampling rate for FSCV, compared to 100 ms. CNT fibers have rough surfaces which trap dopamine and dopamine-o-quinone (DOQ), creating more reversible CVs. CNT yarns and fibers are beneficial for high sensitivity, rapid measurements of neurotransmitters.
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Affiliation(s)
| | - B Jill Venton
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904,
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