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Pireddu G, Fairchild CJ, Niblett SP, Cox SJ, Rotenberg B. Impedance of nanocapacitors from molecular simulations to understand the dynamics of confined electrolytes. Proc Natl Acad Sci U S A 2024; 121:e2318157121. [PMID: 38662549 PMCID: PMC11067016 DOI: 10.1073/pnas.2318157121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 04/01/2024] [Indexed: 05/05/2024] Open
Abstract
Nanoelectrochemical devices have become a promising candidate technology across various applications, including sensing and energy storage, and provide new platforms for studying fundamental properties of electrode/electrolyte interfaces. In this work, we employ constant-potential molecular dynamics simulations to investigate the impedance of gold-aqueous electrolyte nanocapacitors, exploiting a recently introduced fluctuation-dissipation relation. In particular, we relate the frequency-dependent impedance of these nanocapacitors to the complex conductivity of the bulk electrolyte in different regimes, and use this connection to design simple but accurate equivalent circuit models. We show that the electrode/electrolyte interfacial contribution is essentially capacitive and that the electrolyte response is bulk-like even when the interelectrode distance is only a few nanometers, provided that the latter is sufficiently large compared to the Debye screening length. We extensively compare our simulation results with spectroscopy experiments and predictions from analytical theories. In contrast to experiments, direct access in simulations to the ionic and solvent contributions to the polarization allows us to highlight their significant and persistent anticorrelation and to investigate the microscopic origin of the timescales observed in the impedance spectrum. This work opens avenues for the molecular interpretation of impedance measurements, and offers valuable contributions for future developments of accurate coarse-grained representations of confined electrolytes.
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Affiliation(s)
- Giovanni Pireddu
- Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux, CNRS, Sorbonne Université, Physicochimie des Électrolytes et Nanosystèmes Interfaciaux (PHENIX), CNRS, Sorbonne Université, ParisF-75005, France
| | - Connie J. Fairchild
- Yusuf Hamied Department of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Samuel P. Niblett
- Yusuf Hamied Department of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Stephen J. Cox
- Yusuf Hamied Department of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Benjamin Rotenberg
- Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux, CNRS, Sorbonne Université, Physicochimie des Électrolytes et Nanosystèmes Interfaciaux (PHENIX), CNRS, Sorbonne Université, ParisF-75005, France
- Réseau sur le Stockage Electrochimique de l’Energie, Fédération de Recherche CNRS 3459, Amiens Cedex80039, France
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2
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Dotan T, Jog A, Kadan-Jamal K, Avni A, Shacham-Diamand Y. In Vivo Plant Bio-Electrochemical Sensor Using Redox Cycling. BIOSENSORS 2023; 13:219. [PMID: 36831984 PMCID: PMC9953906 DOI: 10.3390/bios13020219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/28/2023] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
This work presents an in vivo stem-mounted sensor for Nicotiana tabacum plants and an in situ cell suspension sensor for Solanum lycopersicum cells. Stem-mounted sensors are mechanically stable and less sensitive to plant and air movements than the previously demonstrated leaf-mounted sensors. Interdigitated-electrode-arrays with a dual working electrode configuration were used with an auxiliary electrode and an Ag/AgCl quasi-reference electrode. Signal amplification by redox cycling is demonstrated for a plant-based sensor responding to enzyme expression induced by different cues in the plants. Functional biosensing is demonstrated, first for constitutive enzyme expression and later, for heat-shock-induced enzyme expression in plants. In the cell suspension with redox cycling, positive detection of the enzyme β-glucuronidase (GUS) was observed within a few minutes after applying the substrate (pNPG, 4-Nitrophenyl β-D-glucopyranoside), following redox reactions of the product (p-nitrophenol (pNP)). It is assumed that the initial reaction is the irreversible reduction of pNP to p-hydroxylaminophenol. Next, it can be either oxidized to p-nitrosophenol or dehydrated and oxidized to aminophenol. Both last reactions are reversible and can be used for redox cycling. The dual-electrode redox-cycling electrochemical signal was an order of magnitude larger than that of conventional single-working electrode transducers. A simple model for the gain is presented, predicting that an even larger gain is possible for sub-micron electrodes. In summary, this work demonstrates, for the first time, a redox cycling-based in vivo plant sensor, where diffusion-based amplification occurs inside a tobacco plant's tissue. The technique can be applied to other plants as well as to medical and environmental monitoring systems.
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Affiliation(s)
- Tali Dotan
- Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
- Department of Material Science and Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Aakash Jog
- Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Kian Kadan-Jamal
- Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
- Department of Material Science and Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Adi Avni
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yosi Shacham-Diamand
- Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
- Department of Material Science and Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
- TAU/TiET Food Security Center of Excellence (TTFSCoE), Thapar Institute of Engineering and Technology, Patiala 147004, India
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Alpuche‐Aviles MA. Particle Impact Electrochemistry. ENCYCLOPEDIA OF ELECTROCHEMISTRY 2021:1-30. [DOI: 10.1002/9783527610426.bard030110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Abstract
Experiments involving collisions between a single entity and the electrode surface have become an active area of research. The electrochemical contribution of individual nanoparticles (NPs), enzymes, and other entities, such as aggregates or agglomerates, can be determined using particle impact experiments. Destructive nanoimpact experiments of materials, such as Ag, and the electrocatalytic amplification (ECA) are used to detect the NP/electrode interactions. This review covers the seminal work, critical theoretical studies, and some recent applications. The applications to electrocatalysis include measurements of electron transfer rate constants on individual nanoparticles. Applications in analytical chemistry have allowed the detection of nonelectroactive species by detecting the collisions of soft materials, e.g. micellar suspensions and proteins have increased the technique's analytical possibilities. With ECA, NPs can be used as tags for the electrochemical detection of bioanalytes such as DNA, proteins, and liposomes. The theory of ECA collisions, including frequency of collision and the size of the electrochemical current transients, are also covered. For nanoimpacts, the charge measured during a NP electrolysis, such as Ag NP, is used to detect the NP. Measurements of NP diameter are possible, but limitations to this analysis are covered. The electron transfer studies to the electrolysis of Ag and of metal oxides are discussed. Finally, key experimental instrumentations are discussed, including instrumentation techniques for the small currents inherent to single NP measurement. The effect of filtering, instrumentations rise time, and sampling frequency are also covered.
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4
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Gutierrez-Portocarrero S, Sauer K, Karunathilake N, Subedi P, Alpuche-Aviles MA. Digital Processing for Single Nanoparticle Electrochemical Transient Measurements. Anal Chem 2020; 92:8704-8714. [PMID: 32510201 DOI: 10.1021/acs.analchem.9b05238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
We demonstrate the use of digital frequency analysis in single nanoparticle electrochemical detection. The method uses fast Fourier transforms (FFT) of single entity electrochemical transients and digital filters. These filters effectively remove noise with the Butterworth filter preserving the amplitude of the fundamental processes in comparison with the rectangle filter. Filtering was done in three different types of experiments: single nanoparticle electrocatalytic amplification, photocatalytic amplification, and nanoimpacts of single entities. In the individual nanoparticle stepwise transients, low-pass filters maintain the step height. Furthermore, a Butterworth band-stop filter preserves the peak height in blip transients if the band-stop cutoff frequencies are compatible with the nanoparticle/electrode transient interactions. In hydrazine oxidation by single Au nanoparticles, digital filtering does not complicate the analysis of the step signal because the stepwise change of the particle-by-particle current is preserved with the rectangle, Bessel and Butterworth low pass filters, with the later minimizing time shifts. In the photocurrent single entity transients, we demonstrate resolving a step smaller than the noise. In photoelectrochemical setups, the background processes are stochastic and appear at distinct frequencies that do not necessarily correlate with the detection frequency (fp), of TiO2 nanoparticles. This lack of correlation indicates that background signals have their characteristic frequencies and that it is advantageous to perform filtering a posteriori. We also discuss selecting the filtering frequencies based on sampling rates and fp. In experiments electrolyzing ZnO, that model nanoimpacts, a band-stop filter can remove environmental noise within the sampling spectral region while preserving relevant information on the current transient. We discuss the limits of Bessel and Butterworth filters for resolving consecutive transients.
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Affiliation(s)
| | - Kiley Sauer
- Department of Chemistry, University of Nevada, Reno, Nevada 89557, United States
| | - Nelum Karunathilake
- Department of Chemistry, University of Nevada, Reno, Nevada 89557, United States
| | - Pradeep Subedi
- Department of Chemistry, University of Nevada, Reno, Nevada 89557, United States
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5
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Chen R, Alanis K, Welle TM, Shen M. Nanoelectrochemistry in the study of single-cell signaling. Anal Bioanal Chem 2020; 412:6121-6132. [PMID: 32424795 DOI: 10.1007/s00216-020-02655-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 04/02/2020] [Accepted: 04/08/2020] [Indexed: 12/28/2022]
Abstract
Label-free biosensing has been the dream of scientists and biotechnologists as reported by Vollmer and Arnold (Nat Methods 5:591-596, 2008). The ability of examining living cells is crucial to cell biology as noted by Fang (Int J Electrochem 2011:460850, 2011). Chemical measurement with electrodes is label-free and has demonstrated capability of studying living cells. In recent years, nanoelectrodes of different functionality have been developed. These nanometer-sized electrodes, coupled with scanning electrochemical microscopy (SECM), have further enabled nanometer spatial resolution study in aqueous environments. Developments in the field of nanoelectrochemistry have allowed measurement of signaling species at single cells, contributing to better understanding of cell biology. Leading studies using nanoelectrochemistry of a variety of cellular signaling molecules, including redox-active neurotransmitter (e.g., dopamine), non-redox-active neurotransmitter (e.g., acetylcholine), reactive oxygen species (ROS), and reactive nitrogen species (RNS), are reviewed here.
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Affiliation(s)
- Ran Chen
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL, 61801, USA
| | - Kristen Alanis
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL, 61801, USA
| | - Theresa M Welle
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL, 61801, USA
| | - Mei Shen
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL, 61801, USA.
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Ino K, Şen M, Shiku H, Matsue T. Micro/nanoelectrochemical probe and chip devices for evaluation of three-dimensional cultured cells. Analyst 2018; 142:4343-4354. [PMID: 29106427 DOI: 10.1039/c7an01442b] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Herein, we present an overview of recent research progress in the development of micro/nanoelectrochemical probe and chip devices for the evaluation of three-dimensional (3D) cultured cells. First, we discuss probe devices: a general outline, evaluation of O2 consumption, enzyme-modified electrodes, evaluation of endogenous enzyme activity, and the collection of cell components from cell aggregates are discussed. The next section is focused on integrated chip devices: a general outline, electrode array devices, smart electrode array devices, droplet detection of 3D cultured cells, cell manipulation using dielectrophoresis (DEP), and electrodeposited hydrogels used for fabrication of 3D cultured cells on chip devices are discussed. Finally, we provide a summary and discussion of future directions of research in this field.
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Affiliation(s)
- Kosuke Ino
- Graduate School of Engineering, Tohoku University, 6-6-11-406 Aramaki-aza Aoba, Aoba-ku, Sendai 980-8579, Japan.
| | - Mustafa Şen
- Department of Biomedical Engineering, Izmir Katip Celebi University, 35620 Cigli, Izmir, Turkey
| | - Hitoshi Shiku
- Graduate School of Engineering, Tohoku University, 6-6-11-406 Aramaki-aza Aoba, Aoba-ku, Sendai 980-8579, Japan.
| | - Tomokazu Matsue
- Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-aza Aoba, Aoba-ku, Sendai 980-8579, Japan.
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7
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Kang S, Nieuwenhuis AF, Mathwig K, Mampallil D, Kostiuchenko ZA, Lemay SG. Single-molecule electrochemistry in nanochannels: probing the time of first passage. Faraday Discuss 2018; 193:41-50. [PMID: 27775135 DOI: 10.1039/c6fd00075d] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The diffusive mass transport of individual redox molecules was probed experimentally in microfabricated nanogap electrodes. The residence times for molecules inside a well-defined detection volume were extracted and the resulting distribution was compared with quantitative analytical predictions from random-walk theory for the time of first passage. The results suggest that a small number of strongly adsorbing sites strongly influence mass transport at trace analyte levels.
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Affiliation(s)
- Shuo Kang
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Ab F Nieuwenhuis
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Klaus Mathwig
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Dileep Mampallil
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Zinaida A Kostiuchenko
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Serge G Lemay
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
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8
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Robinson DA, Edwards MA, Ren H, White HS. Effects of Instrumental Filters on Electrochemical Measurement of Single‐Nanoparticle Collision Dynamics. ChemElectroChem 2018. [DOI: 10.1002/celc.201800696] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Donald A. Robinson
- Department of Chemistry University of Utah, Salt Lake City Utah 84112 United States
| | - Martin A. Edwards
- Department of Chemistry University of Utah, Salt Lake City Utah 84112 United States
| | - Hang Ren
- Department of Chemistry University of Utah, Salt Lake City Utah 84112 United States
| | - Henry S. White
- Department of Chemistry University of Utah, Salt Lake City Utah 84112 United States
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9
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Sokolov SV, Eloul S, Kätelhön E, Batchelor-McAuley C, Compton RG. Electrode-particle impacts: a users guide. Phys Chem Chem Phys 2018; 19:28-43. [PMID: 27918031 DOI: 10.1039/c6cp07788a] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We present a comprehensive guide to nano-impact experiments, in which we introduce newcomers to this rapidly-developing field of research. Central questions are answered regarding required experimental set-ups, categories of materials that can be detected, and the theoretical frameworks enabling the analysis of experimental data. Commonly-encountered issues are considered and presented alongside methods for their solutions.
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Affiliation(s)
- Stanislav V Sokolov
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
| | - Shaltiel Eloul
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
| | - Enno Kätelhön
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
| | - Christopher Batchelor-McAuley
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
| | - Richard G Compton
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
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10
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Zeng Z, Shi X, Mabe T, Christie S, Gilmore G, Smith AW, Wei J. Protein Trapping in Plasmonic Nanoslit and Nanoledge Cavities: The Behavior and Sensing. Anal Chem 2017; 89:5221-5229. [PMID: 28418634 DOI: 10.1021/acs.analchem.6b04493] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel plasmonic nanoledge device was presented to explore the geometry-induced trapping of nanoscale biomolecules and examine a generation of surface plasmon resonance (SPR) for plasmonic sensing. To design an optimal plasmonic device, a semianalytical model was implemented for a quantitative analysis of SPR under plane-wave illumination and a finite-difference time-domain (FDTD) simulation was used to study the optical transmission and refractive index (RI) sensitivity. In addition, total internal reflection fluorescence (TIRF) imaging was used to visualize the migration of fluorescently labeled bovine serum albumin (BSA) into the nanoslits; and fluorescence correlation spectroscopy (FCS) was further used to investigate the diffusion of BSA in the nanoslits. Transmission SPR measurements of free prostate specific antigen (f-PSA), which is similar in size to BSA, were performed to validate the trapping of the molecules via specific binding reactions in the nanoledge cavities. The present study may facilitate further development of single nanomolecule detection and new nanomicrofluidic arrays for effective detection of multiple biomarkers in clinical biofluids.
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Affiliation(s)
- Zheng Zeng
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering (JSNN), University of North Carolina at Greensboro , Greensboro, North Carolina 27401, United States
| | - Xiaojun Shi
- Department of Chemistry, The University of Akron , Akron, Ohio 44325, United States
| | - Taylor Mabe
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering (JSNN), University of North Carolina at Greensboro , Greensboro, North Carolina 27401, United States
| | - Shaun Christie
- Department of Chemistry, The University of Akron , Akron, Ohio 44325, United States
| | - Grant Gilmore
- Department of Chemistry, The University of Akron , Akron, Ohio 44325, United States
| | - Adam W Smith
- Department of Chemistry, The University of Akron , Akron, Ohio 44325, United States
| | - Jianjun Wei
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering (JSNN), University of North Carolina at Greensboro , Greensboro, North Carolina 27401, United States
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11
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Ying YL, Ding Z, Zhan D, Long YT. Advanced electroanalytical chemistry at nanoelectrodes. Chem Sci 2017; 8:3338-3348. [PMID: 28507703 PMCID: PMC5416909 DOI: 10.1039/c7sc00433h] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 02/16/2017] [Indexed: 01/10/2023] Open
Abstract
Nanoelectrodes, with dimensions below 100 nm, have the advantages of high sensitivity and high spatial resolution. These electrodes have attracted increasing attention in various fields such as single cell analysis, single-molecule detection, single particle characterization and high-resolution imaging. The rapid growth of novel nanoelectrodes and nanoelectrochemical methods brings enormous new opportunities in the field. In this perspective, we discuss the challenges, advances, and opportunities for nanoelectrode fabrication, real-time characterizations and high-performance electrochemical instrumentation.
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Affiliation(s)
- Yi-Lun Ying
- School of Chemistry & Molecular Engineering , East China University of Science and Technology , Shanghai , 200237 , P. R. China .
| | - Zhifeng Ding
- Department of Chemistry , University of Western Ontario , 1151 Richmond Street , London , ON N6A 5B7 , Canada
| | - Dongping Zhan
- State Key Laboratory of Physical Chemistry of Solid Surfaces , Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM) , Department of Chemistry , College of Chemistry and Chemical Engineering , Xiamen University , Xiamen , 361005 , P. R. China
| | - Yi-Tao Long
- School of Chemistry & Molecular Engineering , East China University of Science and Technology , Shanghai , 200237 , P. R. China .
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12
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Adly N, Feng L, Krause KJ, Mayer D, Yakushenko A, Offenhäusser A, Wolfrum B. Flexible Microgap Electrodes by Direct Inkjet Printing for Biosensing Application. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/adbi.201600016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Nouran Adly
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
| | - Lingyan Feng
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
- Materials Genome Institute; Shanghai University; 200444 Shanghai China
| | - Kay J. Krause
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
| | - Dirk Mayer
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
| | - Alexey Yakushenko
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
| | - Andreas Offenhäusser
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
| | - Bernhard Wolfrum
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA - Fundamentals of Future Information Technology; Forschungszentrum Jülich; 52425 Jülich Germany
- Neuroelectronics; Munich School of Bioengineering; Department of Electrical and Computer Engineering; Technical University of Munich (TUM) & BCCN Munich; Boltzmannstrasse 11 85748 Garching Germany
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13
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Adly NY, Bachmann B, Krause KJ, Offenhäusser A, Wolfrum B, Yakushenko A. Three-dimensional inkjet-printed redox cycling sensor. RSC Adv 2017. [DOI: 10.1039/c6ra27170g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Electrochemical amplification through redox cycling in an all-inkjet-printed device utilizing four different functional inks.
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Affiliation(s)
- N. Y. Adly
- Institute of Bioelectronics (PGI-8/ICS-8)
- JARA—Fundamentals of Future Information Technology
- Forschungszentrum Jülich
- 52425 Jülich
- Germany
| | - B. Bachmann
- Neuroelectronics
- MSB
- Department of Electrical and Computer Engineering
- Technical University of Munich (TUM) & BCCN Munich
- Garching
| | - K. J. Krause
- Institute of Bioelectronics (PGI-8/ICS-8)
- JARA—Fundamentals of Future Information Technology
- Forschungszentrum Jülich
- 52425 Jülich
- Germany
| | - A. Offenhäusser
- Institute of Bioelectronics (PGI-8/ICS-8)
- JARA—Fundamentals of Future Information Technology
- Forschungszentrum Jülich
- 52425 Jülich
- Germany
| | - B. Wolfrum
- Institute of Bioelectronics (PGI-8/ICS-8)
- JARA—Fundamentals of Future Information Technology
- Forschungszentrum Jülich
- 52425 Jülich
- Germany
| | - A. Yakushenko
- Institute of Bioelectronics (PGI-8/ICS-8)
- JARA—Fundamentals of Future Information Technology
- Forschungszentrum Jülich
- 52425 Jülich
- Germany
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14
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Wolfrum B, Kätelhön E, Yakushenko A, Krause KJ, Adly N, Hüske M, Rinklin P. Nanoscale Electrochemical Sensor Arrays: Redox Cycling Amplification in Dual-Electrode Systems. Acc Chem Res 2016; 49:2031-40. [PMID: 27602780 DOI: 10.1021/acs.accounts.6b00333] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Micro- and nanofabriation technologies have a tremendous potential for the development of powerful sensor array platforms for electrochemical detection. The ability to integrate electrochemical sensor arrays with microfluidic devices nowadays provides possibilities for advanced lab-on-a-chip technology for the detection or quantification of multiple targets in a high-throughput approach. In particular, this is interesting for applications outside of analytical laboratories, such as point-of-care (POC) or on-site water screening where cost, measurement time, and the size of individual sensor devices are important factors to be considered. In addition, electrochemical sensor arrays can monitor biological processes in emerging cell-analysis platforms. Here, recent progress in the design of disease model systems and organ-on-a-chip technologies still needs to be matched by appropriate functionalities for application of external stimuli and read-out of cellular activity in long-term experiments. Preferably, data can be gathered not only at a singular location but at different spatial scales across a whole cell network, calling for new sensor array technologies. In this Account, we describe the evolution of chip-based nanoscale electrochemical sensor arrays, which have been developed and investigated in our group. Focusing on design and fabrication strategies that facilitate applications for the investigation of cellular networks, we emphasize the sensing of redox-active neurotransmitters on a chip. To this end, we address the impact of the device architecture on sensitivity, selectivity as well as on spatial and temporal resolution. Specifically, we highlight recent work on redox-cycling concepts using nanocavity sensor arrays, which provide an efficient amplification strategy for spatiotemporal detection of redox-active molecules. As redox-cycling electrochemistry critically depends on the ability to miniaturize and integrate closely spaced electrode systems, the fabrication of suitable nanoscale devices is of utmost importance for the development of this advanced sensor technology. Here, we address current challenges and limitations, which are associated with different redox cycling sensor array concepts and fabrication approaches. State-of-the-art micro- and nanofabrication technologies based on optical and electron-beam lithography allow precise control of the device layout and have led to a new generation of electrochemical sensor architectures for highly sensitive detection. Yet, these approaches are often expensive and limited to clean-room compatible materials. In consequence, they lack possibilities for upscaling to high-throughput fabrication at moderate costs. In this respect, self-assembly techniques can open new routes for electrochemical sensor design. This is true in particular for nanoporous redox cycling sensor arrays that have been developed in recent years and provide interesting alternatives to clean-room fabricated nanofluidic redox cycling devices. We conclude this Account with a discussion of emerging fabrication technologies based on printed electronics that we believe have the potential of transforming current redox cycling concepts from laboratory tools for fundamental studies and proof-of-principle analytical demonstrations into high-throughput devices for rapid screening applications.
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Affiliation(s)
- Bernhard Wolfrum
- Institute
of Bioelectronics (PGI-8/ICS-8), Forschungszentrum Jülich, 52425 Jülich, Germany
- Neuroelectronics,
IMETUM, Department of Electrical and Computer Engineering, Technical University of Munich, Boltzmannstr. 11, 85748 Garching, Germany
| | - Enno Kätelhön
- Institute
of Bioelectronics (PGI-8/ICS-8), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Alexey Yakushenko
- Institute
of Bioelectronics (PGI-8/ICS-8), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Kay J. Krause
- Institute
of Bioelectronics (PGI-8/ICS-8), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Nouran Adly
- Institute
of Bioelectronics (PGI-8/ICS-8), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Martin Hüske
- Institute
of Bioelectronics (PGI-8/ICS-8), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Philipp Rinklin
- Neuroelectronics,
IMETUM, Department of Electrical and Computer Engineering, Technical University of Munich, Boltzmannstr. 11, 85748 Garching, Germany
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15
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Affiliation(s)
- Pradyumna S. Singh
- Intel
Labs, Intel Corporation, 2200 Mission College Boulevard, Santa Clara, California 95054, United States
| | - Serge G. Lemay
- MESA+
Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
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16
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Oldham KB, Marken F, Myland JC. Theory of unsupported, steady-state, Nernstian, three-ion, twin-electrode, voltammetry: the special case of dual concentration polarization. J Solid State Electrochem 2016. [DOI: 10.1007/s10008-015-3113-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Han L, Wang W, Nsabimana J, Yan JW, Ren B, Zhan D. Single molecular catalysis of a redox enzyme on nanoelectrodes. Faraday Discuss 2016; 193:133-139. [DOI: 10.1039/c6fd00061d] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Due to a high turnover coefficient, redox enzymes can serve as current amplifiers which make it possible to explore their catalytic mechanism by electrochemistry at the level of single molecules. On modified nanoelectrodes, the voltammetric behavior of a horseradish peroxidase (HRP) catalyzed hydroperoxide reduction no longer presents a continuous current response, but a staircase current response. Furthermore, single catalytic incidents were captured through a collision mode at a constant potential, from which the turnover number of HRP can be figured out statistically. In addition, the catalytic behavior is dynamic which may be caused by the orientation status of HRP on the surface of the electrode. This modified nanoelectrode methodology provides an electrochemical approach to investigate the single-molecule catalysis of redox enzymes.
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Affiliation(s)
- Lianhuan Han
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials (iChEM)
- Department of Chemistry
- College of Chemistry and Chemical Engineering
- Xiamen University
| | - Wei Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials (iChEM)
- Department of Chemistry
- College of Chemistry and Chemical Engineering
- Xiamen University
| | - Jacques Nsabimana
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials (iChEM)
- Department of Chemistry
- College of Chemistry and Chemical Engineering
- Xiamen University
| | - Jia-Wei Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials (iChEM)
- Department of Chemistry
- College of Chemistry and Chemical Engineering
- Xiamen University
| | - Bin Ren
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials (iChEM)
- Department of Chemistry
- College of Chemistry and Chemical Engineering
- Xiamen University
| | - Dongping Zhan
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials (iChEM)
- Department of Chemistry
- College of Chemistry and Chemical Engineering
- Xiamen University
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18
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Kanno Y, Ino K, Shiku H, Matsue T. A local redox cycling-based electrochemical chip device with nanocavities for multi-electrochemical evaluation of embryoid bodies. LAB ON A CHIP 2015; 15:4404-4414. [PMID: 26481771 DOI: 10.1039/c5lc01016k] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
An electrochemical device, which consists of electrode arrays, nanocavities, and microwells, was developed for multi-electrochemical detection with high sensitivity. A local redox cycling-based electrochemical (LRC-EC) system was used for multi-electrochemical detection and signal amplification. The LRC-EC system consists of n(2) sensors with only 2n bonding pads for external connection. The nanocavities fabricated in the sensor microwells enable significant improvement of the signal amplification compared with the previous devices we have developed. The present device was successfully applied for evaluation of embryoid bodies (EBs) from embryonic stem (ES) cells via electrochemical measurements of alkaline phosphatase (ALP) activity in the EBs. In addition, the EBs were successfully trapped in the sensor microwells of the device using dielectrophoresis (DEP) manipulation, which led to high-throughput cell analysis. This device is considered to be useful for multi-electrochemical detection and imaging for bioassays including cell analysis.
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Affiliation(s)
- Yusuke Kanno
- Graduate School of Environmental Studies, Tohoku University, Japan.
| | - Kosuke Ino
- Graduate School of Environmental Studies, Tohoku University, Japan.
| | - Hitoshi Shiku
- Graduate School of Environmental Studies, Tohoku University, Japan.
| | - Tomokazu Matsue
- Graduate School of Environmental Studies, Tohoku University, Japan. and WPI-Advanced Institute for Materials Research, Tohoku University, Japan
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19
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Chen CH, Ravenhill ER, Momotenko D, Kim YR, Lai SCS, Unwin PR. Impact of Surface Chemistry on Nanoparticle-Electrode Interactions in the Electrochemical Detection of Nanoparticle Collisions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11932-42. [PMID: 26448140 DOI: 10.1021/acs.langmuir.5b03033] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The electrochemical detection of a single nanoparticle (NP) at a support electrode can provide key information on surface chemistry and fundamental electron transfer (ET) properties at the nanoscale. This study employs scanning electrochemical cell microscopy (SECCM) as a fluidic device to both deliver individual citrate-capped gold nanoparticles (AuNPs) and study the interactions between them and a range of alkanethiol-modified Au electrodes with different terminal groups, namely, -COOH, -OH, and -CH3. Single NP collisions were detected through the AuNP-mediated ET reaction of Fe(CN)6(4-/3-) in aqueous solution. The collision frequency, residence time, and current-time characteristics of AuNPs are greatly affected by the terminal groups of the alkanethiol. Methods to determine these parameters, including the effect of the instrument response function, and derive ET kinetics are outlined. To further understand the interactions of AuNPs with these surfaces, atomic force microscopy (AFM) force measurements were performed using citrate-modified Au-coated AFM tips and the same alkanethiol-modified Au substrates in aqueous solution at the same potential bias as for the AuNP collision experiments. Force curves on OH-terminated surfaces showed no repulsion and negligible adhesion force. In contrast, a clear repulsion (on approach) was seen for COOH-terminated surface and adhesion forces (on retract) were observed for both COOH- and CH3-terminated surfaces. These interactions help to explain the residence times and collision frequencies in AuNP collisions. More generally, as the interfacial properties probed by AFM appear to be amplified in NP collision experiments, and new features also become evident, it is suggested that such experiments provide a new means of probing surface chemistry at the nanoscale.
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Affiliation(s)
- Chang-Hui Chen
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Emma R Ravenhill
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Dmitry Momotenko
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Yang-Rae Kim
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Stanley C S Lai
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
- MESA+ Institute for Nanotechnology, University of Twente , PO Box 217, 7500 AE Enschede, The Netherlands
| | - Patrick R Unwin
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
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20
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Byers JC, Paulose Nadappuram B, Perry D, McKelvey K, Colburn AW, Unwin PR. Single Molecule Electrochemical Detection in Aqueous Solutions and Ionic Liquids. Anal Chem 2015; 87:10450-6. [DOI: 10.1021/acs.analchem.5b02569] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Joshua C. Byers
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | | | - David Perry
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Kim McKelvey
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Alex W. Colburn
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Patrick R. Unwin
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
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21
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Rosenstein JK, Lemay SG, Shepard KL. Single-molecule bioelectronics. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2015; 7:475-93. [PMID: 25529538 PMCID: PMC4476964 DOI: 10.1002/wnan.1323] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 08/04/2014] [Accepted: 10/29/2014] [Indexed: 01/08/2023]
Abstract
Experimental techniques that interface single biomolecules directly with microelectronic systems are increasingly being used in a wide range of powerful applications, from fundamental studies of biomolecules to ultra-sensitive assays. In this study, we review several technologies that can perform electronic measurements of single molecules in solution: ion channels, nanopore sensors, carbon nanotube field-effect transistors, electron tunneling gaps, and redox cycling. We discuss the shared features among these techniques that enable them to resolve individual molecules, and discuss their limitations. Recordings from each of these methods all rely on similar electronic instrumentation, and we discuss the relevant circuit implementations and potential for scaling these single-molecule bioelectronic interfaces to high-throughput arrayed sensing platforms.
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Affiliation(s)
| | - Serge G Lemay
- MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands
| | - Kenneth L Shepard
- Departments of Electrical and Biomedical Engineering, Columbia University, New York, NY, USA
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22
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Batchelor-McAuley C, Kätelhön E, Barnes EO, Compton RG, Laborda E, Molina A. Recent Advances in Voltammetry. ChemistryOpen 2015; 4:224-60. [PMID: 26246984 PMCID: PMC4522172 DOI: 10.1002/open.201500042] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Indexed: 11/10/2022] Open
Abstract
Recent progress in the theory and practice of voltammetry is surveyed and evaluated. The transformation over the last decade of the level of modelling and simulation of experiments has realised major advances such that electrochemical techniques can be fully developed and applied to real chemical problems of distinct complexity. This review focuses on the topic areas of: multistep electrochemical processes, voltammetry in ionic liquids, the development and interpretation of theories of electron transfer (Butler-Volmer and Marcus-Hush), advances in voltammetric pulse techniques, stochastic random walk models of diffusion, the influence of migration under conditions of low support, voltammetry at rough and porous electrodes, and nanoparticle electrochemistry. The review of the latter field encompasses both the study of nanoparticle-modified electrodes, including stripping voltammetry and the new technique of 'nano-impacts'.
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Affiliation(s)
- Christopher Batchelor-McAuley
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of OxfordSouth Parks Road, Oxford, OX1 3QZ, UK
| | - Enno Kätelhön
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of OxfordSouth Parks Road, Oxford, OX1 3QZ, UK
| | - Edward O Barnes
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of OxfordSouth Parks Road, Oxford, OX1 3QZ, UK
| | - Richard G Compton
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of OxfordSouth Parks Road, Oxford, OX1 3QZ, UK
| | - Eduardo Laborda
- Departamento de Química Física, Facultad de Química, Regional Campus of International Excellence ‘Campus Mare Nostrum’, Universidad de Murcia30100, Murcia, Spain
| | - Angela Molina
- Departamento de Química Física, Facultad de Química, Regional Campus of International Excellence ‘Campus Mare Nostrum’, Universidad de Murcia30100, Murcia, Spain
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23
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Guha S, Schmalz K, Wenger C, Herzel F. Self-calibrating highly sensitive dynamic capacitance sensor: towards rapid sensing and counting of particles in laminar flow systems. Analyst 2015; 140:3262-72. [PMID: 25793229 DOI: 10.1039/c5an00187k] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this report we propose a sensor architecture and a corresponding read-out technique on silicon for the detection of dynamic capacitance change. This approach can be applied to rapid particle counting and single particle sensing in a fluidic system. The sensing principle is based on capacitance variation of an interdigitated electrode (IDE) structure embedded in an oscillator circuit. The capacitance scaling of the IDE results in frequency modulation of the oscillator. A demodulator architecture is employed to provide a read-out of the frequency modulation caused by the capacitance change. A self-calibrating technique is employed at the read-out amplifier stage. The capacitance variation of the IDE due to particle flow causing frequency modulation and the corresponding demodulator read-out has been analytically modelled. Experimental verification of the established model and the functionality of the sensor chip were shown using a modulating capacitor independent of fluidic integration. The initial results show that the sensor is capable of detecting frequency changes of the order of 100 parts per million (PPM), which translates to a shift of 1.43 MHz at 14.3 GHz operating frequency. It is also shown that a capacitance change every 3 μs can be accurately detected.
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Affiliation(s)
- S Guha
- IHP, Leibniz Institute for Innovative Microelectronics, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
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24
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Feldberg SW, Edwards MA. Current response for a single redox moiety trapped in a closed generator-collector system: the role of capacitive coupling. Anal Chem 2015; 87:3778-83. [PMID: 25738594 DOI: 10.1021/ac504375j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A theoretical model is proposed to describe the steady-state average limiting current associated with a single redox moiety (ox or red) trapped in a closed generator-collector system along with excess supporting electrolyte. By "closed" we mean that neither solvent nor solutes can enter or leave the system. The potential difference, EOE - ERE, between the oxidizing electrode (OE) and the reducing electrode (RE) is maintained constant with the values of EOE and ERE chosen so that the operative faradaic electrode processes are very fast, i.e., red = ox + nETe(-) (kox = ∞) at the OE and ox + nETe(-) = red (kred = ∞) at the RE. Because there is only a single redox moiety the faradaic process occurs at only one electrode at a time while current at the other electrode is purely capacitive (we refer to this as capacitive coupling). We propose that a two-step process is required to transfer nETqe coulombs (qe is the absolute value of the elemental electronic charge). The first step is associated with diffusion (approximated as a random walk) of a single red moiety to the OE where it is oxidized to ox with a concomitant transfer of qstep1 (= nETqe/(1 + AOECOE/ARECRE)) coulombs; the second step is associated with the diffusion (random walk) of the newly formed single ox moiety to the RE with the concomitant transfer of qstep2 (= nETqe/(1 + ARECRE/AOECOE)) coulombs (ARE,AOE andCRE,COEare the areas (cm(2)) and differential capacitances (farads cm(-2)) of the corresponding electrodes). The total charge transferred in the two steps is nETqe(= qstep1 + qstep2). Transport of the redox moiety from one electrode to the other is accomplished by a random walk. The probability density function (pdf) and cumulative density function (CDF) for the duration of a full redox cycle are presented as the analytical solution to a 1-dimensional bounded random-walk problem (confirmed by numerical simulation). These show that tfull, the average time for the full redox cycle (step 1 + step 2), is equal to L(2)/D where L is the intraelectrode distance and D is the diffusion coefficient. The average steady-state limiting current is shown to be described by the familiar expression for a generator-collector system: ilim = (qstep1 + qstep2)/tfull = nETqe/tfull = nETqeD/L(2).
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Affiliation(s)
- Stephen W Feldberg
- †Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Martin A Edwards
- ‡Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
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25
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Abstract
Digital simulations are a commonly used tool in electrochemical and electroanalytical research. However, even though the employed computational methods often feature significant complexity, testing routines are rarely specified or discussed in literature. In this work, we address this topic and describe approaches towards testing electrochemical simulation software. While focussing on simple systems featuring Nernstian reactions in 1 : 1 stoichiometries, we guide through rigorous testing processes of one- and two dimensional simulations with regard to applications in cyclic voltammetry. To this end, we compile expressions for the calculation of key values as references, discuss the conduction of convergence studies, and suggest approaches to automated software testing.
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Affiliation(s)
- Enno Kätelhön
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK.
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26
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Fan L, Liu Y, Xiong J, White HS, Chen S. Electron-transfer kinetics and electric double layer effects in nanometer-wide thin-layer cells. ACS NANO 2014; 8:10426-10436. [PMID: 25211307 DOI: 10.1021/nn503780b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Redox cycling in nanometer-wide thin-layer cells holds great promise in ultrasensitive voltammetric detection and in probing fast heterogeneous electron-transfer kinetics. Quantitative understanding of the influence of the nanometer gap distance on the redox processes in the thin-layer cells is of crucial importance for reliable data analysis. We present theoretical consideration on the voltammetric behaviors associated with redox cycling of electroactive molecules between two electrodes separated by nanometer widths. Emphasis is placed on the weakness of the commonly used Butler-Volmer theory and the classic Marcus-Hush theory in describing the electrochemical heterogeneous electron-transfer kinetics at potentials significantly removed from the formal potential of redox moieties and, in addition, the effect of the electric-double-layer on the electron-transfer kinetics and mass transport dynamics of charged redox species. The steady-state voltammetric responses, obtained by using the Butler-Volmer and Marcus-Hush models and that predicted by the more realistic electron-transfer kinetics formulism, which is based on the alignments of the density of states between the electrode continuum and the Gaussian distribution of redox agents, and by inclusion of the electric-double-layer effect, are compared through systematic finite element simulations. The effect of the gap width between the electrodes, the standard rate constant and reorganization energy for the electron-transfer reactions, and the charges of the redox moieties are considered. On the basis of the simulation results, the reliability of the conventional voltammetric analysis based on the Butler-Volmer kinetic model and diffusion transport equations is discussed for nanometer-wide thin-layer cells.
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Affiliation(s)
- Lixin Fan
- Hubei Key Laboratory of Electrochemical Power Sources, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University , Wuhan 430072, China
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27
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Gross AJ, Marken F. Boron-doped diamond dual-plate microtrench electrode for generator–collector chloride/chlorine sensing. Electrochem commun 2014. [DOI: 10.1016/j.elecom.2014.06.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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28
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Kätelhön E, Compton RG. Understanding nano-impacts: impact times and near-wall hindered diffusion. Chem Sci 2014. [DOI: 10.1039/c4sc02288b] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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29
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Kätelhön E, Mayer D, Banzet M, Offenhäusser A, Wolfrum B. Nanocavity crossbar arrays for parallel electrochemical sensing on a chip. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:1137-1143. [PMID: 25161846 PMCID: PMC4143123 DOI: 10.3762/bjnano.5.124] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 06/25/2014] [Indexed: 06/03/2023]
Abstract
We introduce a novel device for the mapping of redox-active compounds at high spatial resolution based on a crossbar electrode architecture. The sensor array is formed by two sets of 16 parallel band electrodes that are arranged perpendicular to each other on the wafer surface. At each intersection, the crossing bars are separated by a ca. 65 nm high nanocavity, which is stabilized by the surrounding passivation layer. During operation, perpendicular bar electrodes are biased to potentials above and below the redox potential of species under investigation, thus, enabling repeated subsequent reactions at the two electrodes. By this means, a redox cycling current is formed across the gap that can be measured externally. As the nanocavity devices feature a very high current amplification in redox cycling mode, individual sensing spots can be addressed in parallel, enabling high-throughput electrochemical imaging. This paper introduces the design of the device, discusses the fabrication process and demonstrates its capabilities in sequential and parallel data acquisition mode by using a hexacyanoferrate probe.
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Affiliation(s)
- Enno Kätelhön
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany. Current address: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QZ, United Kingdom
| | - Dirk Mayer
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Marko Banzet
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Andreas Offenhäusser
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany
- Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany
| | - Bernhard Wolfrum
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany
- Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany
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30
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Mathwig K, Aartsma TJ, Canters GW, Lemay SG. Nanoscale methods for single-molecule electrochemistry. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2014; 7:383-404. [PMID: 25000819 DOI: 10.1146/annurev-anchem-062012-092557] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The development of experiments capable of probing individual molecules has led to major breakthroughs in fields ranging from molecular electronics to biophysics, allowing direct tests of knowledge derived from macroscopic measurements and enabling new assays that probe population heterogeneities and internal molecular dynamics. Although still somewhat in their infancy, such methods are also being developed for probing molecular systems in solution using electrochemical transduction mechanisms. Here we outline the present status of this emerging field, concentrating in particular on optical methods, metal-molecule-metal junctions, and electrochemical nanofluidic devices.
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Affiliation(s)
- Klaus Mathwig
- MESA+ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, the Netherlands; ,
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31
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Kätelhön E, Krause KJ, Mathwig K, Lemay SG, Wolfrum B. Noise phenomena caused by reversible adsorption in nanoscale electrochemical devices. ACS NANO 2014; 8:4924-4930. [PMID: 24694343 DOI: 10.1021/nn500941g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We theoretically investigate reversible adsorption in electrochemical devices on a molecular level. To this end, a computational framework is introduced, which is based on 3D random walks including probabilities for adsorption and desorption events at surfaces. We demonstrate that this approach can be used to investigate adsorption phenomena in electrochemical sensors by analyzing experimental noise spectra of a nanofluidic redox cycling device. The evaluation of simulated and experimental results reveals an upper limit for the average adsorption time of ferrocene dimethanol of ∼200 μs. We apply our model to predict current noise spectra of further electrochemical experiments based on interdigitated arrays and scanning electrochemical microscopy. Since the spectra strongly depend on the molecular adsorption characteristics of the detected analyte, we can suggest key indicators of adsorption phenomena in noise spectroscopy depending on the geometric aspect of the experimental setup.
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Affiliation(s)
- Enno Kätelhön
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich , 52425 Jülich, Germany
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32
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Ino K, Kanno Y, Nishijo T, Komaki H, Yamada Y, Yoshida S, Takahashi Y, Shiku H, Matsue T. Densified Electrochemical Sensors Based on Local Redox Cycling between Vertically Separated Electrodes in Substrate Generation/Chip Collection and Extended Feedback Modes. Anal Chem 2014; 86:4016-23. [DOI: 10.1021/ac500435d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Kosuke Ino
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Yusuke Kanno
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Taku Nishijo
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Hirokazu Komaki
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Yuta Yamada
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Shinya Yoshida
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Yasufumi Takahashi
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Hitoshi Shiku
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
| | - Tomokazu Matsue
- Graduate School of Environmental Studies and §WPI Advanced Institute
for Materials Research, Tohoku University, Sendai, Japan 980-8579
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33
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Kätelhön E, Barnes EO, Krause KJ, Wolfrum B, Compton RG. Equality of diffusion-limited chronoamperometric currents to equal area spherical and cubic nanoparticles on a supporting electrode surface. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.01.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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34
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Hüske M, Stockmann R, Offenhäusser A, Wolfrum B. Redox cycling in nanoporous electrochemical devices. NANOSCALE 2014; 6:589-598. [PMID: 24247480 DOI: 10.1039/c3nr03818a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Nanoscale redox cycling is a powerful technique for detecting electrochemically active molecules, based on fast repetitive oxidation and reduction reactions. An ideal implementation of redox cycling sensors can be realized by nanoporous dual-electrode systems in easily accessible and scalable geometries. Here, we introduce a multi-electrode array device with highly efficient nanoporous redox cycling sensors. Each of the sensors holds up to 209,000 well defined nanopores with minimal pore radii of less than 40 nm and an electrode separation of ~100 nm. We demonstrate the efficiency of the nanopore array by screening a large concentration range over three orders of magnitude with area-specific sensitivities of up to 81.0 mA (cm(-2) mM(-1)) for the redox-active probe ferrocene dimethanol. Furthermore, due to the specific geometry of the material, reaction kinetics has a unique potential-dependent impact on the signal characteristics. As a result, redox cycling experiments in the nanoporous structure allow studies on heterogeneous electron transfer reactions revealing a surprisingly asymmetric transfer coefficient.
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Affiliation(s)
- Martin Hüske
- Institute of Bioelectronics (PGI-8/ICS-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, D-52425 Jülich, Germany.
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35
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Hasnat MA, Gross AJ, Dale SEC, Barnes EO, Compton RG, Marken F. A dual-plate ITO–ITO generator–collector microtrench sensor: surface activation, spatial separation and suppression of irreversible oxygen and ascorbate interference. Analyst 2014; 139:569-75. [DOI: 10.1039/c3an01826a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Li D, Liu J, Barrow CJ, Yang W. Protein electrochemistry using graphene-based nano-assembly: an ultrasensitive electrochemical detection of protein molecules via nanoparticle–electrode collisions. Chem Commun (Camb) 2014; 50:8197-200. [DOI: 10.1039/c4cc03384a] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Kang S, Nieuwenhuis AF, Mathwig K, Mampallil D, Lemay SG. Electrochemical single-molecule detection in aqueous solution using self-aligned nanogap transducers. ACS NANO 2013; 7:10931-10937. [PMID: 24279688 DOI: 10.1021/nn404440v] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Electrochemical detection of individual molecular tags in nanochannels may enable cost-effective, massively parallel analysis and diagnostics platforms. Here we demonstrate single-molecule detection of prototypical analytes in aqueous solution based on redox cycling in 40 nm nanogap transducers. These nanofluidic devices are fabricated using standard microfabrication techniques combined with a self-aligned approach that minimizes gap size and dead volume. We demonstrate the detection of three common redox mediators at physiological salt concentrations.
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Affiliation(s)
- Shuo Kang
- MESA+ Institute for Nanotechnology, University of Twente , PO Box 217, 7500 AE Enschede, The Netherlands
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38
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39
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Le Thi Ngoc L, Jin M, Wiedemair J, van den Berg A, Carlen ET. Large area metal nanowire arrays with tunable sub-20 nm nanogaps. ACS NANO 2013; 7:5223-34. [PMID: 23647306 DOI: 10.1021/nn4009559] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We report a new top-down nanofabrication technology to realize large area metal nanowire (m-NW) arrays with tunable sub-20 nm separation nanogaps without the use of chemical etching or milling of the metal layer. The m-NW array nanofabrication technology is based on a self-regulating metal deposition process that is facilitated by closely spaced and isolated heterogeneous template surfaces that confine the metal deposition into two dimensions, and therefore, electrically isolated parallel arrays of m-NW can be realized with uniform and controllable nanogaps. Au-NW and Ag-NW arrays are presented with high-density ~10(5) NWs cm(-1), variable NW diameters down to ~50 nm, variable nanogaps down to ~5 nm, and very large nanogap length density ~1 km cm(-2). The m-NW arrays are designed and implemented as interdigitated nanoelectrodes for electrochemical applications and as plasmonic substrates where the coupled-mode localized surface plasmon resonance (LSPR) wavelength in the nanogaps between adjacent m-NW dimers can be precisely tuned to match any excitation source in the range from 500 to 1000 nm, thus providing optimal local electromagnetic field enhancement. A spatially averaged (n = 2500) surface-enhanced Raman scattering (SERS) analytical enhancement factor of (1.2 ± 0.1) × 10(7) is demonstrated from a benzenethiol monolayer chemisorbed on a Au-NW array substrate with LSPR wavelength matched to a He-Ne laser source.
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Affiliation(s)
- Loan Le Thi Ngoc
- BIOS Lab on a Chip Group and MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands
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40
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Kätelhön E, Krause KJ, Singh PS, Lemay SG, Wolfrum B. Noise Characteristics of Nanoscaled Redox-Cycling Sensors: Investigations Based on Random Walks. J Am Chem Soc 2013; 135:8874-81. [DOI: 10.1021/ja3121313] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Enno Kätelhön
- Institute of Bioelectronics
(PGI-8/ICS-8) and JARA—Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich,
Germany
| | - Kay J. Krause
- Institute of Bioelectronics
(PGI-8/ICS-8) and JARA—Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich,
Germany
| | - Pradyumna S. Singh
- MESA+ Institute
for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede,
The Netherlands
| | - Serge G. Lemay
- MESA+ Institute
for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede,
The Netherlands
| | - Bernhard Wolfrum
- Institute of Bioelectronics
(PGI-8/ICS-8) and JARA—Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich,
Germany
- Institute
of Physics, RWTH Aachen University, 52074
Aachen, Germany
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41
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Yakushenko A, Kätelhön E, Wolfrum B. Parallel On-Chip Analysis of Single Vesicle Neurotransmitter Release. Anal Chem 2013; 85:5483-90. [DOI: 10.1021/ac4006183] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Alexey Yakushenko
- Institute of Bioelectronics
(PGI-8/ICS-8) and JARA—Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich,
Germany
| | - Enno Kätelhön
- Institute of Bioelectronics
(PGI-8/ICS-8) and JARA—Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich,
Germany
| | - Bernhard Wolfrum
- Institute of Bioelectronics
(PGI-8/ICS-8) and JARA—Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich,
Germany
- IV. Institute of
Physics, RWTH Aachen University, 52074
Aachen, Germany
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42
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Pushing the Limits of Electrical Detection of Ultralow Flows in Nanofluidic Channels. MICROMACHINES 2013. [DOI: 10.3390/mi4020138] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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43
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Lemay SG, Kang S, Mathwig K, Singh PS. Single-molecule electrochemistry: present status and outlook. Acc Chem Res 2013; 46:369-77. [PMID: 23270398 DOI: 10.1021/ar300169d] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The development of methods for detecting and manipulating matter at the level of individual macromolecules represents one of the key scientific advancements of recent decades. These techniques allow us to get information that is largely unobtainable otherwise, such as the magnitudes of microscopic forces, mechanistic details of catalytic processes, macromolecular population heterogeneities, and time-resolved, step-by-step observation of complex kinetics. Methods based on optical, mechanical, and ionic-conductance signal transduction are particularly developed. However, there is scope for new approaches that can broaden the range of molecular systems that we can study at this ultimate level of sensitivity and for developing new analytical methods relying on single-molecule detection. Approaches based on purely electrical detection are particularly appealing in the latter context, since they can be easily combined with microelectronics or fluidic devices on a single microchip to create large parallel assays at relatively low cost. A form of electrical signal transduction that has so far remained relatively underdeveloped at the single-molecule level is the direct detection of the charge transferred in electrochemical processes. The reason for this is simple: only a few electrons are transferred per molecule in a typical faradaic reaction, a heterogeneous charge-transfer reaction that occurs at the electrode's surface. Detecting this tiny amount of charge is impossible using conventional electrochemical instrumentation. A workaround is to use redox cycling, in which the charge transferred is amplified by repeatedly reducing and oxidizing analyte molecules as they randomly diffuse between a pair of electrodes. For this process to be sufficiently efficient, the electrodes must be positioned within less than 100 nm of each other, and the analyte must remain between the electrodes long enough for the measurement to take place. Early efforts focused on tip-based nanoelectrodes, descended from scanning electrochemical microscopy, to create suitable geometries. However, it has been challenging to apply these technologies broadly. In this Account, we describe our alternative approach based on electrodes embedded in microfabricated nanochannels, so-called nanogap transducers. Microfabrication techniques grant a high level of reproducibility and control over the geometry of the devices, permitting systematic development and characterization. We have employed these devices to demonstrate single-molecule sensitivity. This method shows good agreement with theoretical analysis based on the Brownian motion of discrete molecules, but only once the finite time resolution of the experimental apparatus is taken into account. These results highlight both the random nature of single-molecule signals and the complications that it can introduce in data interpretation. We conclude this Account with a discussion on how scientists can overcome this limitation in the future to create a new experimental platform that can be generally useful for both fundamental studies and analytical applications.
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Affiliation(s)
- Serge G. Lemay
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Shuo Kang
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Klaus Mathwig
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Pradyumna S. Singh
- MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
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