1
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Zerdoumi R, Quast T, Tetteh EB, Kim M, Li L, Dieckhöfer S, Schuhmann W. Integration of Scanning Electrochemical Microscopy and Scanning Electrochemical Cell Microscopy in a Bifunctional Nanopipette toward Simultaneous Mapping of Activity and Selectivity in Electrocatalysis. Anal Chem 2024; 96:10886-10892. [PMID: 38925554 PMCID: PMC11238158 DOI: 10.1021/acs.analchem.4c00149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 05/11/2024] [Accepted: 05/20/2024] [Indexed: 06/28/2024]
Abstract
Scanning electrochemical microscopy (SECM) and scanning electrochemical cell microscopy (SECCM) were integrated in a single bifunctional probe for simultaneous mapping of the oxygen reduction current and the oxidation current of the produced H2O2. The dual probe is fabricated from a double-barrel θ capillary, comprising one open barrel filled with the electrolyte and another filled with pyrolytic carbon. Pt is deposited with a gas injection system (GIS) at the end of the carbon barrel. The probe integrates the advantages of both SECM and SECCM by forming an electrochemical droplet cell that embeds the Pt working electrode of the carbon barrel directly into the electrolyte meniscus formed upon sample contact from the electrolyte barrel. The versatility of the dual probe is demonstrated by mapping the oxygen reduction reaction (ORR) current and the H2O2 oxidation current of a Pt microstrip on a gold substrate. This allows simultaneous localized electrochemical measurements, highlighting the potential of the dual probe for broader applications in characterizing the electrocatalytic properties of materials.
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Affiliation(s)
- Ridha Zerdoumi
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Thomas Quast
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Emmanuel Batsa Tetteh
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Moonjoo Kim
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Lejing Li
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Stefan Dieckhöfer
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Wolfgang Schuhmann
- Analytical Chemistry-Center
for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
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2
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Poderyte M, Ramanavicius A, Valiūnienė A. Exploring the Living Cell: Applications and Advances of Scanning Electrochemical Microscopy. Crit Rev Anal Chem 2024:1-12. [PMID: 38557222 DOI: 10.1080/10408347.2024.2328135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
A living cell is a complex network of molecular, biochemical and physiological processes. Cellular activities, such as ion transport, metabolic processes, and cell-cell interactions can be determined electrochemically by detecting the electrons or ions exchanged in these processes. Electrochemical methods often are noninvasive, and they can enable the real-time monitoring of cellular processes. Scanning electrochemical microscopy (SECM) is an advanced scanning probe electroanalysis technique that can map the surface topography and local reactivity of a substrate with high precision at the micro- or nanoscale. By measuring electrochemical signals, such as redox reactions, ion fluxes, and pH changes, SECM can provide valuable insights into cellular activity. As a result of its compatibility with liquid medium measurements and its nondestructive nature, SECM has gained popularity in living cell research. This review aims to furnish an overview of SECM, elucidating its principles, applications, and its potential to contribute significantly to advancements in cell biology, electroporation, and biosensors. As a multidisciplinary tool, SECM is distinguished by its ability to unravel the intricacies of living cells and offers promising avenues for breakthroughs in our understanding of cellular complexity.
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Affiliation(s)
- Margarita Poderyte
- Faculty of Chemistry and Geosciences, Institute of Chemistry, Vilnius University, Vilnius, Lithuania
| | - Arunas Ramanavicius
- Faculty of Chemistry and Geosciences, Institute of Chemistry, Vilnius University, Vilnius, Lithuania
- Laboratory of Nanotechnology, State Research Institute Centre of Physical Sciences and Technology, Vilnius, Lithuania
| | - Aušra Valiūnienė
- Faculty of Chemistry and Geosciences, Institute of Chemistry, Vilnius University, Vilnius, Lithuania
- State Research Institute Center for Physical Sciences and Technology, Vilnius, Lithuania
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3
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Mulder EJ, Moser B, Delgado J, Steinhardt RC, Esser-Kahn AP. Evidence of collective influence in innate sensing using fluidic force microscopy. Front Immunol 2024; 15:1340384. [PMID: 38322261 PMCID: PMC10844469 DOI: 10.3389/fimmu.2024.1340384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 01/05/2024] [Indexed: 02/08/2024] Open
Abstract
The innate immune system initiates early response to infection by sensing molecular patterns of infection through pattern-recognition receptors (PRRs). Previous work on PRR stimulation of macrophages revealed significant heterogeneity in single cell responses, suggesting the importance of individual macrophage stimulation. Current methods either isolate individual macrophages or stimulate a whole culture and measure individual readouts. We probed single cell NF-κB responses to localized stimuli within a naïve culture with Fluidic Force Microscopy (FluidFM). Individual cells stimulated in naïve culture were more sensitive compared to individual cells in uniformly stimulated cultures. In cluster stimulation, NF-κB activation decreased with increased cell density or decreased stimulation time. Our results support the growing body of evidence for cell-to-cell communication in macrophage activation, and limit potential mechanisms. Such a mechanism might be manipulated to tune macrophage sensitivity, and the density-dependent modulation of sensitivity to PRR signals could have relevance to biological situations where macrophage density increases.
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Affiliation(s)
| | | | | | | | - Aaron P. Esser-Kahn
- Esser-Kahn Lab, Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, United States
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4
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Huang K, Wang YH, Zhang H, Wang TY, Liu XH, Liu L, Jiang H, Wang XM. Application and outlook of electrochemical technology in single-cell analysis. Biosens Bioelectron 2023; 242:115741. [PMID: 37816284 DOI: 10.1016/j.bios.2023.115741] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 10/04/2023] [Indexed: 10/12/2023]
Abstract
Cellular heterogeneity, especially in some important diseased cells like tumor cells, acts as an invisible driver for disease development like cancer progression in the tumor ecosystem, contributing to differences in the macroscopic and microscopic detection of disease lesions like tumors. Traditional analysis techniques choose group information masked by the mean as the analysis sample, making it difficult to achieve precise diagnosis and target treatment, on which could be shed light via the single-cell level determination/bioanalysis. Hence, in this article we have reviewed the special characteristic differences among various kinds of typical single-cell bioanalysis strategies and electrochemical techniques, and then focused on the recent advance and special bio-applications of electrochemiluminescence and micro-nano electrochemical sensing mediated in single-cell bioimaging & bioanalysis. Especially, we have summarized the relevant research exploration of the possibility to establish the in-situ single-cell electrochemical methods to detect cell heterogeneity through determination of specific biomolecules and bioimaging of some important biological processes. Eventually, this review has explored some important advances of electrochemical single-cell detection techniques for the real-time cellular bioimaging and diagnostics of some disease lesions like tumors. It raises the possibility to provide the specific in-situ platform to exploit the versatile, sensitive, and high-resolution electrochemical single-cell analysis for the promising biomedical applications like rapid tracing of some disease lesions or in vivo bioimaging for precise cancer theranostics.
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Affiliation(s)
- Ke Huang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
| | - Yi Han Wang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
| | - Hao Zhang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
| | - Ting Ya Wang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
| | - Xiao Hui Liu
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
| | - Liu Liu
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.
| | - Hui Jiang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.
| | - Xue Mei Wang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.
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5
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Cremin K, Meloni GN, Valavanis D, Soyer OS, Unwin PR. Can Single Cell Respiration be Measured by Scanning Electrochemical Microscopy (SECM)? ACS MEASUREMENT SCIENCE AU 2023; 3:361-370. [PMID: 37868362 PMCID: PMC10588932 DOI: 10.1021/acsmeasuresciau.3c00019] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/13/2023] [Accepted: 06/13/2023] [Indexed: 10/24/2023]
Abstract
Ultramicroelectrode (UME), or, equivalently, microelectrode, probes are increasingly used for single-cell measurements of cellular properties and processes, including physiological activity, such as metabolic fluxes and respiration rates. Major challenges for the sensitivity of such measurements include: (i) the relative magnitude of cellular and UME fluxes (manifested in the current); and (ii) issues around the stability of the UME response over time. To explore the extent to which these factors impact the precision of electrochemical cellular measurements, we undertake a systematic analysis of measurement conditions and experimental parameters for determining single cell respiration rates via the oxygen consumption rate (OCR) in single HeLa cells. Using scanning electrochemical microscopy (SECM), with a platinum UME as the probe, we employ a self-referencing measurement protocol, rarely employed in SECM, whereby the UME is repeatedly approached from bulk solution to a cell, and a short pulse to oxygen reduction reaction (ORR) potential is performed near the cell and in bulk solution. This approach enables the periodic tracking of the bulk UME response to which the near-cell response is repeatedly compared (referenced) and also ensures that the ORR near the cell is performed only briefly, minimizing the effect of the electrochemical process on the cell. SECM experiments are combined with a finite element method (FEM) modeling framework to simulate oxygen diffusion and the UME response. Taking a realistic range of single cell OCR to be 1 × 10-18 to 1 × 10-16 mol s-1, results from the combination of FEM simulations and self-referencing SECM measurements show that these OCR values are at, or below, the present detection sensitivity of the technique. We provide a set of model-based suggestions for improving these measurements in the future but highlight that extraordinary improvements in the stability and precision of SECM measurements will be required if single cell OCR measurements are to be realized.
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Affiliation(s)
- Kelsey Cremin
- Bio-Electrical
Engineering Innovation Hub, Department of Chemistry, Molecular Analytical
Science Centre for Doctoral Training (MAS CDT), School of Life Sciences, the University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Gabriel N. Meloni
- Bio-Electrical
Engineering Innovation Hub, Department of Chemistry, Molecular Analytical
Science Centre for Doctoral Training (MAS CDT), School of Life Sciences, the University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Dimitrios Valavanis
- Bio-Electrical
Engineering Innovation Hub, Department of Chemistry, Molecular Analytical
Science Centre for Doctoral Training (MAS CDT), School of Life Sciences, the University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Orkun S. Soyer
- Bio-Electrical
Engineering Innovation Hub, Department of Chemistry, Molecular Analytical
Science Centre for Doctoral Training (MAS CDT), School of Life Sciences, the University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Patrick R. Unwin
- Bio-Electrical
Engineering Innovation Hub, Department of Chemistry, Molecular Analytical
Science Centre for Doctoral Training (MAS CDT), School of Life Sciences, the University of Warwick, Coventry CV4 7AL, United Kingdom
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6
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Park S, Kumar S, Maier CS, Kreth J, Koley D. Simultaneous Chemical Mapping of Live Biofilm Microenvironmental pH and Hydrogen Peroxide in Real Time with a Triple Scanning Electrochemical Microscopy Tip. Anal Chem 2023; 95:6332-6340. [PMID: 37018485 PMCID: PMC10485357 DOI: 10.1021/acs.analchem.2c05258] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Dental plaque biofilm is a complex ecosystem. The distribution of microbial species in the biofilm is heavily influenced by local chemical interactions that result from diverse metabolic activities and the nature of the released molecules. As a relevant example, H2O2-producing bacteria can antagonize disease-associated bacteria, leading to the maintenance of a healthy oral microbiome. Herein, we report the development of a triple-sensor (redox, pH, and H2O2) scanning electrochemical microscopy (SECM) tip capable of simultaneously mapping the pH and H2O2 concentration produced by a dental plaque-derived multispecies biofilm grown on hydroxyapatite. The pH sensor of the triple SECM tip showed a near Nernstian slope of -71.1 ± 2 mV/pH (N = 3), whereas the H2O2 sensor showed a slope of -0.052 ± 0.002 nA/μM H2O2 at pH 7.2 and a detection limit of 1.0 ± 0.2 μM (N = 7). There is no significant difference in the sensitivities of H2O2 sensors at pH 6.2, 7.2, and 8.2 at 95% CI (N = 7). The pH and H2O2 sensors demonstrated excellent reversibility with response times of 3 and 5 s, respectively, along with reliable stability over 4 h at 37 °C. The sensors did not show any cross talk between pH and H2O2 concentration ([H2O2]) measurements, highlighting the accuracy and versatility of the SECM tip. Simultaneous chemical imaging of pH and [H2O2] across the biofilm revealed a clustered distribution of local H2O2 concentrations, ranging from 0 to 17 μM. Conversely, the local pH remained constant at 7.2. The relation of local chemical profiles and the distribution of bacterial species within the oral microbiome was experimentally investigated in the context of bacterial H2O2 antagonism. The benefit of clustered H2O2 production was that the total area of H2O2 produced by smaller clusters was 67% more than that of a single cluster with the same starting number of bacteria. Thus, this triple SECM tip can potentially be used to study local molecular mechanisms that result in dysbiosis of the oral microbiome.
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Affiliation(s)
- Suji Park
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Sriram Kumar
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Claudia S Maier
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Jens Kreth
- Department of Restorative Dentistry, Oregon Health and Science University, Portland, Oregon 97201, United States
| | - Dipankar Koley
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
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7
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Rabinowitz J, Hartel AJW, Dayton H, Fabbri JD, Jo J, Dietrich LEP, Shepard KL. Charge Mapping of Pseudomonas aeruginosa Using a Hopping Mode Scanning Ion Conductance Microscopy Technique. Anal Chem 2023; 95:5285-5292. [PMID: 36920847 PMCID: PMC10359948 DOI: 10.1021/acs.analchem.2c05303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Scanning ion conductance microscopy (SICM) is a topographic imaging technique capable of probing biological samples in electrolyte conditions. SICM enhancements have enabled surface charge detection based on voltage-dependent signals. Here, we show how the hopping mode SICM method (HP-SICM) can be used for rapid and minimally invasive surface charge mapping. We validate our method usingPseudomonas aeruginosaPA14 (PA) cells and observe a surface charge density of σPA = -2.0 ± 0.45 mC/m2 that is homogeneous within the ∼80 nm lateral scan resolution. This biological surface charge is detected from at least 1.7 μm above the membrane (395× the Debye length), and the long-range charge detection is attributed to electroosmotic amplification. We show that imaging with a nanobubble-plugged probe reduces perturbation of the underlying sample. We extend the technique to PA biofilms and observe a charge density exceeding -20 mC/m2. We use a solid-state calibration to quantify surface charge density and show that HP-SICM cannot be quantitatively described by a steady-state finite element model. This work contributes to the body of scanning probe methods that can uniquely contribute to microbiology and cellular biology.
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Affiliation(s)
- Jake Rabinowitz
- Department of Electrical Engineering, Columbia University, New York, New York 10027, United States
| | - Andreas J W Hartel
- Department of Electrical Engineering, Columbia University, New York, New York 10027, United States.,Department of Biology, Columbia University, New York, New York 10027, United States
| | - Hannah Dayton
- Department of Biology, Columbia University, New York, New York 10027, United States
| | - Jason D Fabbri
- Department of Electrical Engineering, Columbia University, New York, New York 10027, United States
| | - Jeanyoung Jo
- Department of Biology, Columbia University, New York, New York 10027, United States
| | - Lars E P Dietrich
- Department of Biology, Columbia University, New York, New York 10027, United States
| | - Kenneth L Shepard
- Department of Electrical Engineering, Columbia University, New York, New York 10027, United States
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8
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Hu W, Ma Y, Zhan Z, Hussain D, Hu C. Robotic Intracellular Electrochemical Sensing for Adherent Cells. CYBORG AND BIONIC SYSTEMS 2022; 2022:9763420. [PMID: 36285318 PMCID: PMC9494721 DOI: 10.34133/2022/9763420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/25/2022] [Indexed: 11/22/2022] Open
Abstract
Nanopipette-based observation of intracellular biochemical processes is an important approach to revealing the intrinsic characteristics and heterogeneity of cells for better investigation of disease progression or early disease diagnosis. However, the manual operation needs a skilled operator and faces problems such as low throughput and poor reproducibility. This paper proposes an automated nanopipette-based microoperation system for cell detection, three-dimensional nonovershoot positioning of the nanopipette tip in proximity to the cell of interest, cell approaching and proximity detection between nanopipette tip and cell surface, and cell penetration and detection of the intracellular reactive oxygen species (ROS). A robust focus algorithm based on the number of cell contours was proposed for adherent cells, which have sharp peaks while retaining unimodality. The automated detection of adherent cells was evaluated on human umbilical cord vein endothelial cells (HUVEC) and NIH/3T3 cells, which provided an average of 95.65% true-positive rate (TPR) and 7.59% false-positive rate (FPR) for in-plane cell detection. The three-dimensional nonovershoot tip positioning of the nanopipette was achieved by template matching and evaluated under the interference of cells. Ion current feedback was employed for the proximity detection between the nanopipette tip and cell surface. Finally, cell penetration and electrochemical detection of ROS were demonstrated on human breast cancer cells and zebrafish embryo cells. This work provides a systematic approach for automated intracellular sensing for adherent cells, laying a solid foundation for high-throughput detection, diagnosis, and classification of different forms of biochemical reactions within single cells.
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Affiliation(s)
- Weikang Hu
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Yanmei Ma
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Zhen Zhan
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Danish Hussain
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, China
- Department of Mechatronics Engineering, National University of Sciences and Technology, Islamabad, Pakistan
| | - Chengzhi Hu
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, China
- Guangdong Provincial Key Laboratory of Human-Augmentation and Rehabilitation Robotics in Universities, Southern University of Science and Technology, Shenzhen, China
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9
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Liu YL, Zhao YX, Li YB, Ye ZY, Zhang JJ, Zhou Y, Gao TY, Li F. Recent Advances of Nanoelectrodes for Single-Cell Electroanalysis: From Extracellular, Intercellular to Intracellular. JOURNAL OF ANALYSIS AND TESTING 2022. [DOI: 10.1007/s41664-022-00223-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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10
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Unwin P. Concluding remarks: next generation nanoelectrochemistry - next generation nanoelectrochemists. Faraday Discuss 2022; 233:374-391. [PMID: 35229863 DOI: 10.1039/d2fd00020b] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aim of this paper is to describe the scientific journey taken to arrive at present-day nanoelectrochemistry and consider how the area might develop in the future, particularly in light of papers presented at this Faraday Discussion. By adopting a generational approach, this brief contribution traces the story of the nanoelectrochemistry family within the broader electrochemistry field, with a focus on scientific capability and themes that were important to each generation. I shall consider research questions and the impact of technology that was developed or available in each period. Nanoelectrochemistry is still somewhat niche, but is attracting increasing numbers of researchers. It is set to become a major part of electrochemistry and interfacial science. It is studied by people with a fairly unique skillset, and I shall speculate on the skills and expertise that will be needed by nanoelectrochemists to address the challenges and opportunities that lie ahead. I conclude by asking: who will be the nanoelectrochemists of the future and what will they do?
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Affiliation(s)
- Patrick Unwin
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK.
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11
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Shao Y, He P, Yu Z, Liang X, Shao Y. Modulation of ionic current behaviors based on a dual-channel micro/nano-pipette with ternary-form-charged model. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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Abstract
Scanning ion conductance microscopy (SICM) has emerged as a versatile tool for studies of interfaces in biology and materials science with notable utility in biophysical and electrochemical measurements. The heart of the SICM is a nanometer-scale electrolyte filled glass pipette that serves as a scanning probe. In the initial conception, manipulations of ion currents through the tip of the pipette and appropriate positioning hardware provided a route to recording micro- and nanoscopic mapping of the topography of surfaces. Subsequent advances in instrumentation, probe design, and methods significantly increased opportunities for SICM beyond recording topography. Hybridization of SICM with coincident characterization techniques such as optical microscopy and faradaic electrodes have brought SICM to the forefront as a tool for nanoscale chemical measurement for a wide range of applications. Modern approaches to SICM realize an important tool in analytical, bioanalytical, biophysical, and materials measurements, where significant opportunities remain for further exploration. In this review, we chronicle the development of SICM from the perspective of both the development of instrumentation and methods and the breadth of measurements performed.
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Affiliation(s)
- Cheng Zhu
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Kaixiang Huang
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Natasha P Siepser
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Lane A Baker
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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13
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Teahan J, Perry D, Chen B, McPherson IJ, Meloni GN, Unwin PR. Scanning Ion Conductance Microscopy: Surface Charge Effects on Electroosmotic Flow Delivery from a Nanopipette. Anal Chem 2021; 93:12281-12288. [PMID: 34460243 DOI: 10.1021/acs.analchem.1c01868] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Scanning ion conductance microscopy (SICM) is a powerful and versatile technique that allows an increasingly wide range of interfacial properties and processes to be studied. SICM employs a nanopipette tip that contains electrolyte solution and a quasi-reference counter electrode (QRCE), to which a potential is applied with respect to a QRCE in a bathing solution, in which the tip is placed. The work herein considers the potential-controlled delivery of uncharged electroactive molecules (solute) from an SICM tip to a working electrode substrate to determine the effect of the substrate on electroosmotic flow (EOF). Specifically, the local delivery of hydroquinone from the tip to a carbon fiber ultramicroelectrode (CF UME) provides a means of quantifying the rate of mass transport from the nanopipette and mapping electroactivity via the CF UME current response for hydroquinone oxidation to benzoquinone. EOF, and therefore species delivery, has a particularly strong dependence on the charge of the substrate surface at close nanopipette-substrate surface separations, with implications for retaining neutral solute within the tip predelivery and for the delivery process itself, both controlled via the applied tip potential. Finite element method (FEM) simulations of mass transport and reactivity are used to explain the experimental observations and identify the nature of EOF, including unusual flow patterns under certain conditions. The combination of experimental results with FEM simulations provides new insights on mass transport in SICM that will enhance quantitative applications and enable new possibilities for the use of nanopipettes for local delivery.
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Affiliation(s)
- James Teahan
- MAS Centre for Doctoral Training, University of Warwick, Coventry CV4 7AL, United Kingdom.,Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - David Perry
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Baoping Chen
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Ian J McPherson
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Gabriel N Meloni
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Patrick R Unwin
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
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14
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Analysis and improvement of positioning reliability and accuracy of theta pipette configuration for scanning ion conductance microscopy. Ultramicroscopy 2021; 224:113240. [PMID: 33689886 DOI: 10.1016/j.ultramic.2021.113240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 02/02/2021] [Accepted: 02/27/2021] [Indexed: 11/21/2022]
Abstract
Scanning ion conductance microscopy (SICM) as an emerging non-contact scanning probe microscopy technique and featuring its strong in-situ detectability for soft and viscous samples, is increasingly used in biomedical and materials related studies. In SICM measurements, employing theta pipette as SICM probe to scan sample is an effective method to extend the applications of SICM for multi-parameter measurement. There are two crucial but still unclear issues that influence the reliability and accuracy of the usage of theta pipette in the SICM measurements, which are the safe feedback threshold and the horizontal measurement offset. In this work, aiming at the theta pipette configuration of SICM, we systematically investigated the two issues of the theta pipette by both finite element method (FEM) simulation and SICM experiments. The FEM analysis results show that the safe feedback threshold of the one side barrel of the theta pipette is above 99.5%, and the horizontal measurement offset is ~0.53 times of the inner radius of the probe tip. Based on this, we proposed an improved scanning method used by the theta pipette to solve the reliability and accuracy problems caused by the feedback threshold too close to the reference current (100%) and the measurement offset error at the tip radius level. Then through testing the polydimethylsiloxane (PDMS) samples with different embossed patterns with the improved method of SICM, we can conclude that the improved method can enhance the scanning reliability by adding the double barrels approaching process and increase the positioning accuracy by compensating an offset distance. The theoretical analysis and the improved scanning method in this work demonstrate more property and usage details of the theta pipette, and further improve the reliability and accuracy of the diversified multifunctional applications of the theta pipette for SICM to meet the increasingly complex and precise research needs.
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15
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Liu Y, Du J, Wang M, Zhang J, Liu C, Li X. Recent Progress in Quantitatively Monitoring Vesicular Neurotransmitter Release and Storage With Micro/Nanoelectrodes. Front Chem 2021; 8:591311. [PMID: 33505953 PMCID: PMC7831278 DOI: 10.3389/fchem.2020.591311] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/20/2020] [Indexed: 01/31/2023] Open
Abstract
Exocytosis is one of the essential steps for chemical signal transmission between neurons. In this process, vesicles dock and fuse with the plasma membrane and release the stored neurotransmitters through fusion pores into the extracellular space, and all of these steps are governed with various molecules, such as proteins, ions, and even lipids. Quantitatively monitoring vesicular neurotransmitter release in exocytosis and initial neurotransmitter storage in individual vesicles is significant for the study of chemical signal transmission of the central nervous system (CNS) and neurological diseases. Electrochemistry with micro/nanoelectrodes exhibits great spatial-temporal resolution and high sensitivity. It can be used to examine the exocytotic kinetics from the aspect of neurotransmitters and quantify the neurotransmitter storage in individual vesicles. In this review, we first introduce the recent advances of single-cell amperometry (SCA) and the nanoscale interface between two immiscible electrolyte solutions (nanoITIES), which can monitor the quantity and release the kinetics of electrochemically and non-electrochemically active neurotransmitters, respectively. Then, the development and application of the vesicle impact electrochemical cytometry (VIEC) and intracellular vesicle impact electrochemical cytometry (IVIEC) and their combination with other advanced techniques can further explain the mechanism of neurotransmitter storage in vesicles before exocytosis. It has been proved that these electrochemical techniques have great potential in the field of neuroscience.
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Affiliation(s)
| | | | | | | | - Chunlan Liu
- Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing, China
| | - Xianchan Li
- Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing, China
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16
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A cost-efficient approach for simultaneous scanning electrochemical microscopy and scanning ion conductance microscopy. MONATSHEFTE FUR CHEMIE 2020. [DOI: 10.1007/s00706-020-02635-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AbstractA novel and cost-efficient probe fabrication method yielding probes for performing simultaneous scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM) is presented. Coupling both techniques allows distinguishing topographical and electrochemical activity information obtained by SECM. Probes were prepared by deposition of photoresist onto platinum-coated, pulled fused silica capillaries, which resulted in a pipette probe with an integrated ring ultramicroelectrode. The fabricated probes were characterized by means of cyclic voltammetry and scanning electron microscopy. The applicability of probes was demonstrated by measuring and distinguishing topography and electrochemical activity of a model substrate. In addition, porous boron-doped diamond samples were investigated via simultaneously performed SECM and SICM.
Graphic abstract
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17
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Caniglia G, Kranz C. Scanning electrochemical microscopy and its potential for studying biofilms and antimicrobial coatings. Anal Bioanal Chem 2020; 412:6133-6148. [PMID: 32691088 PMCID: PMC7442582 DOI: 10.1007/s00216-020-02782-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/08/2020] [Accepted: 06/19/2020] [Indexed: 02/06/2023]
Abstract
Biofilms are known to be well-organized microbial communities embedded in an extracellular polymeric matrix, which supplies bacterial protection against external stressors. Biofilms are widespread and diverse, and despite the considerable large number of publications and efforts reported regarding composition, structure and cell-to-cell communication within biofilms in the last decades, the mechanisms of biofilm formation, the interaction and communication between bacteria are still not fully understood. This knowledge is required to understand why biofilms form and how we can combat them or how we can take advantage of these sessile communities, e.g. in biofuel cells. Therefore, in situ and real-time monitoring of nutrients, metabolites and quorum sensing molecules is of high importance, which may help to fill that knowledge gap. This review focuses on the potential of scanning electrochemical microscopy (SECM) as a versatile method for in situ studies providing temporal and lateral resolution in order to elucidate cell-to-cell communication, microbial metabolism and antimicrobial impact, e.g. of antimicrobial coatings through the study of electrochemical active molecules. Given the complexity and diversity of biofilms, challenges and limitations will be also discussed.
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Affiliation(s)
- Giada Caniglia
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee, 11, 89081, Ulm, Germany
| | - Christine Kranz
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee, 11, 89081, Ulm, Germany.
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18
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Jiao Y, Zhuang J, Zheng Q, Liao X. A High Accuracy Ion Conductance Imaging Method Based on the Approach Curve Spectrum. Ultramicroscopy 2020; 215:113025. [PMID: 32485394 DOI: 10.1016/j.ultramic.2020.113025] [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: 02/29/2020] [Revised: 04/28/2020] [Accepted: 05/16/2020] [Indexed: 01/13/2023]
Abstract
Scanning ion conductance microscopy (SICM), as an emerging non-contact in situ topography measurement tool with nano resolution, has been increasingly used in recent years in biomedicine, electrochemistry and materials science. In the conventional measurement method of SICM, the sample topography is constructed according to the position of the probe at the feedback threshold of the ion current. Nevertheless, for different structures, a constant threshold cannot maintain a constant probe-sample distance. This phenomenon makes the measurement topography inconsistent with the real sample surface. In order to solve this problem and improve the measurement accuracy of SICM, a new ion conductance imaging method based on the approach curve spectrum is proposed in this work. In the new method, the local feature around the measurement point is firstly evaluated according to the change rate of ion current. Secondly, based on the local feature, the corresponding approach curve is searched from the prior approach curve spectrum to accurately evaluate the distance between the probe and the sample. Finally, the sample topography is constructed by the probe position subtracting the probe-sample distance. In this paper, we verify the feasibility of the new imaging method by combining finite element theory and experiments. To examine the measurement accuracy, the standard strip silicon and cylindrical polydimethylsiloxane (PDMS) samples are tested, and the improved imaging method can obtain the topography closer to the real samples and reduce the volumetric measurement error by 5.4%. The implementation of the new imaging method will further promote SICM application in related research fields.
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Affiliation(s)
- Yangbohan Jiao
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China; School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jian Zhuang
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China; School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Qiangqiang Zheng
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China; School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xiaobo Liao
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China; School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China; School of Manufacturing Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China
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19
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Verlinden EJ, Madadelahi M, Sarajlic E, Shamloo A, Engel AH, Staufer U, Ghatkesar MK. Volume and concentration dosing in picolitres using a two-channel microfluidic AFM cantilever. NANOSCALE 2020; 12:10292-10305. [PMID: 32363366 DOI: 10.1039/c9nr10494a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We introduce a two-channel microfluidic atomic force microscopy (AFM) cantilever that combines the nanomechanical sensing functionality of an AFM cantilever with the ability to manipulate fluids of picolitres or smaller volumes through nanoscale apertures near the cantilever tip. Each channel is connected to a separate fluid reservoir, which can be independently controlled by pressure. Various systematic experiments with fluorescent liquids were done by either injecting the liquids from the on-chip reservoir or aspirating directly through the nanoscale apertures at the tip. A flow rate analysis of volume dosing, aspiration and concentration dosing inside the liquid medium was performed. To understand the fluid behaviour, an analytical model based on the hydrodynamic resistance, as well as numerical flow simulations of single and multi-phase conditions were performed and compared. By applying pressures between -500 mbar and 500 mbar to the reservoirs of the probe with respect to the ambient pressure, flow rates ranging from 10 fl s-1 to 83 pl s-1 were obtained inside the channels of the cantilever as predicted by the analytical model. The smallest dosing flow rate through the apertures was 720 fl s-1, which was obtained with a 10 mbar pressure on one reservoir and ambient pressure on the other. The solute concentration in the outflow could be tuned to values between 0% and 100% by pure convection and to values between 17.5% and 90% in combination with diffusion. The results prove that this new probe enables handling multiple fluids with the scope to inject different concentrations of analytes inside a single living cell and also perform regular AFM functionalities.
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Affiliation(s)
- E J Verlinden
- Department of Precision and Microsystems Engineering, Delft University of Technology, The Netherlands.
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20
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Schofield Z, Meloni GN, Tran P, Zerfass C, Sena G, Hayashi Y, Grant M, Contera SA, Minteer SD, Kim M, Prindle A, Rocha P, Djamgoz MBA, Pilizota T, Unwin PR, Asally M, Soyer OS. Bioelectrical understanding and engineering of cell biology. J R Soc Interface 2020; 17:20200013. [PMID: 32429828 PMCID: PMC7276535 DOI: 10.1098/rsif.2020.0013] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/17/2020] [Indexed: 02/07/2023] Open
Abstract
The last five decades of molecular and systems biology research have provided unprecedented insights into the molecular and genetic basis of many cellular processes. Despite these insights, however, it is arguable that there is still only limited predictive understanding of cell behaviours. In particular, the basis of heterogeneity in single-cell behaviour and the initiation of many different metabolic, transcriptional or mechanical responses to environmental stimuli remain largely unexplained. To go beyond the status quo, the understanding of cell behaviours emerging from molecular genetics must be complemented with physical and physiological ones, focusing on the intracellular and extracellular conditions within and around cells. Here, we argue that such a combination of genetics, physics and physiology can be grounded on a bioelectrical conceptualization of cells. We motivate the reasoning behind such a proposal and describe examples where a bioelectrical view has been shown to, or can, provide predictive biological understanding. In addition, we discuss how this view opens up novel ways to control cell behaviours by electrical and electrochemical means, setting the stage for the emergence of bioelectrical engineering.
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Affiliation(s)
- Zoe Schofield
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Gabriel N. Meloni
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
| | - Peter Tran
- Department of Chemical and Biological Engineering, Northwestern University, Chicago, IL 60611, USA
| | - Christian Zerfass
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Giovanni Sena
- Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Yoshikatsu Hayashi
- Department of Biomedical Engineering, School of Biological Sciences, University of Reading, Reading RG6 6AH, UK
| | - Murray Grant
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Sonia A. Contera
- Clarendon Laboratory, Physics Department, University of Oxford, Parks Road, Oxford OX1 3PU, UK
| | - Shelley D. Minteer
- Department of Chemistry, University of Utah, 315 S 1400 E, Salt Lake City, Utah 84112, USA
| | - Minsu Kim
- Department of Physics, Emory University, Atlanta, GA 30322, USA
| | - Arthur Prindle
- Department of Chemical and Biological Engineering, Northwestern University, Chicago, IL 60611, USA
| | - Paulo Rocha
- Centre for Biosensors, Bioelectronics and Biodevices (C3Bio), Department of Electronic and Electrical Engineering, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Mustafa B. A. Djamgoz
- Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Teuta Pilizota
- Systems and Synthetic Biology Centre and School of Biological Sciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh EH9 3FF, UK
| | - Patrick R. Unwin
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
| | - Munehiro Asally
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Orkun S. Soyer
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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21
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Benarroch JM, Asally M. The Microbiologist’s Guide to Membrane Potential Dynamics. Trends Microbiol 2020; 28:304-314. [DOI: 10.1016/j.tim.2019.12.008] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/25/2019] [Accepted: 12/09/2019] [Indexed: 10/25/2022]
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22
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Affiliation(s)
- Si-Min Lu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Yue-Yi Peng
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Yi-Lun Ying
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Yi-Tao Long
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
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23
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Synchronous Electrical Conductance‐ and Electron Tunnelling‐Scanning Electrochemical Microscopy Measurements. ChemElectroChem 2020. [DOI: 10.1002/celc.201901721] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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24
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Zhang Y, Takahashi Y, Hong SP, Liu F, Bednarska J, Goff PS, Novak P, Shevchuk A, Gopal S, Barozzi I, Magnani L, Sakai H, Suguru Y, Fujii T, Erofeev A, Gorelkin P, Majouga A, Weiss DJ, Edwards C, Ivanov AP, Klenerman D, Sviderskaya EV, Edel JB, Korchev Y. High-resolution label-free 3D mapping of extracellular pH of single living cells. Nat Commun 2019; 10:5610. [PMID: 31811139 PMCID: PMC6898398 DOI: 10.1038/s41467-019-13535-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 11/13/2019] [Indexed: 01/05/2023] Open
Abstract
Dynamic mapping of extracellular pH (pHe) at the single-cell level is critical for understanding the role of H+ in cellular and subcellular processes, with particular importance in cancer. While several pHe sensing techniques have been developed, accessing this information at the single-cell level requires improvement in sensitivity, spatial and temporal resolution. We report on a zwitterionic label-free pH nanoprobe that addresses these long-standing challenges. The probe has a sensitivity > 0.01 units, 2 ms response time, and 50 nm spatial resolution. The platform was integrated into a double-barrel nanoprobe combining pH sensing with feedback-controlled distance dependance via Scanning Ion Conductance Microscopy. This allows for the simultaneous 3D topographical imaging and pHe monitoring of living cancer cells. These classes of nanoprobes were used for real-time high spatiotemporal resolution pHe mapping at the subcellular level and revealed tumour heterogeneity of the peri-cellular environments of melanoma and breast cancer cells.
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Affiliation(s)
- Yanjun Zhang
- Department of Medicine, Imperial College London, London, W12 0NN, UK.
- Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, 300052, China.
| | - Yasufumi Takahashi
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Saitama, 332-0012, Japan
| | - Sung Pil Hong
- Department of Surgery and Cancer, Imperial College London, London, W12 0NN, UK
| | - Fengjie Liu
- Department of Earth Science & Engineering, Imperial College London, London, SW7 2AZ, UK
| | - Joanna Bednarska
- Department of Medicine, Imperial College London, London, W12 0NN, UK
| | - Philip S Goff
- Cell Biology Research Centre, Molecular and Clinical Sciences Research Institute, St George's, University of London, London, SW17 0RE, UK
| | - Pavel Novak
- Department of Medicine, Imperial College London, London, W12 0NN, UK
- National University of Science and Technology "MISIS", Leninskiy prospect 4, 119991, Moscow, Russian Federation
| | - Andrew Shevchuk
- Department of Medicine, Imperial College London, London, W12 0NN, UK
| | - Sahana Gopal
- Department of Medicine, Imperial College London, London, W12 0NN, UK
| | - Iros Barozzi
- Department of Surgery and Cancer, Imperial College London, London, W12 0NN, UK
| | - Luca Magnani
- Department of Surgery and Cancer, Imperial College London, London, W12 0NN, UK
| | - Hideki Sakai
- Department of Pharmaceutical Physiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, 930-0194, Japan
| | - Yoshimoto Suguru
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan
| | - Takuto Fujii
- Department of Pharmaceutical Physiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, 930-0194, Japan
| | - Alexander Erofeev
- National University of Science and Technology "MISIS", Leninskiy prospect 4, 119991, Moscow, Russian Federation
- Department of Chemistry, Lomonosov Moscow State University, Leninskiye gory 1-3, GSP-1, 119991, Moscow, Russian Federation
| | - Peter Gorelkin
- National University of Science and Technology "MISIS", Leninskiy prospect 4, 119991, Moscow, Russian Federation
| | - Alexander Majouga
- Department of Chemistry, Lomonosov Moscow State University, Leninskiye gory 1-3, GSP-1, 119991, Moscow, Russian Federation
| | - Dominik J Weiss
- Department of Earth Science & Engineering, Imperial College London, London, SW7 2AZ, UK
| | | | - Aleksandar P Ivanov
- Department of Chemistry, Imperial College London, Molecular Science Research Hub, London, W12 0BZ, UK
| | - David Klenerman
- Department of Chemistry, University of Cambridge, London, CB2 1EW, UK
| | - Elena V Sviderskaya
- Cell Biology Research Centre, Molecular and Clinical Sciences Research Institute, St George's, University of London, London, SW17 0RE, UK.
| | - Joshua B Edel
- Department of Chemistry, Imperial College London, Molecular Science Research Hub, London, W12 0BZ, UK.
| | - Yuri Korchev
- Department of Medicine, Imperial College London, London, W12 0NN, UK.
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
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25
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Watanabe S, Kitazawa S, Sun L, Kodera N, Ando T. Development of high-speed ion conductance microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:123704. [PMID: 31893861 DOI: 10.1063/1.5118360] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Scanning ion conductance microscopy (SICM) can image the surface topography of specimens in ionic solutions without mechanical probe-sample contact. This unique capability is advantageous for imaging fragile biological samples but its highest possible imaging rate is far lower than the level desired in biological studies. Here, we present the development of high-speed SICM. The fast imaging capability is attained by a fast Z-scanner with active vibration control and pipette probes with enhanced ion conductance. By the former, the delay of probe Z-positioning is minimized to sub-10 µs, while its maximum stroke is secured at 6 μm. The enhanced ion conductance lowers a noise floor in ion current detection, increasing the detection bandwidth up to 100 kHz. Thus, temporal resolution 100-fold higher than that of conventional systems is achieved, together with spatial resolution around 20 nm.
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Affiliation(s)
- Shinji Watanabe
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Satoko Kitazawa
- Department of Physics, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Linhao Sun
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Noriyuki Kodera
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Toshio Ando
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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26
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Sun L, Shigyou K, Ando T, Watanabe S. Thermally Driven Approach To Fill Sub-10-nm Pipettes with Batch Production. Anal Chem 2019; 91:14080-14084. [PMID: 31589026 DOI: 10.1021/acs.analchem.9b03848] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Typically, utilization of small nanopipettes results in either high sensitivity or spatial resolution in modern nanoscience and nanotechnology. However, filling a nanopipette with a sub-10-nm pore diameter remains a significant challenge. Here, we introduce a thermally driven approach to filling sub-10-nm pipettes with batch production, regardless of their shape. A temperature gradient is applied to transport water vapor from the backside of nanopipettes to the tip region until bubbles are completely removed from this region. The electrical contact and pore size for filling nanopipettes are confirmed by current-voltage and transmission electron microscopy (TEM) measurements, respectively. In addition, we quantitatively compare the pore size between the TEM characterization and estimation on the basis of pore radius and conductance. The validity of this method provides a foundation for highly sensitive detection of single molecules and high spatial resolution imaging of nanostructures.
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Affiliation(s)
- Linhao Sun
- Nano Life Science Institute (WPI-NanoLSI) , Kanazawa University , Kakuma-machi , Kanazawa 920-1192 , Japan
| | - Kazuki Shigyou
- Nano Life Science Institute (WPI-NanoLSI) , Kanazawa University , Kakuma-machi , Kanazawa 920-1192 , Japan
| | - Toshio Ando
- Nano Life Science Institute (WPI-NanoLSI) , Kanazawa University , Kakuma-machi , Kanazawa 920-1192 , Japan
| | - Shinji Watanabe
- Nano Life Science Institute (WPI-NanoLSI) , Kanazawa University , Kakuma-machi , Kanazawa 920-1192 , Japan
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27
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Deprey K, Becker L, Kritzer J, Plückthun A. Trapped! A Critical Evaluation of Methods for Measuring Total Cellular Uptake versus Cytosolic Localization. Bioconjug Chem 2019; 30:1006-1027. [PMID: 30882208 PMCID: PMC6527423 DOI: 10.1021/acs.bioconjchem.9b00112] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Biomolecules have many properties that make them promising for intracellular therapeutic applications, but delivery remains a key challenge because large biomolecules cannot easily enter the cytosol. Furthermore, quantification of total intracellular versus cytosolic concentrations remains demanding, and the determination of delivery efficiency is thus not straightforward. In this review, we discuss strategies for delivering biomolecules into the cytosol and briefly summarize the mechanisms of uptake for these systems. We then describe commonly used methods to measure total cellular uptake and, more selectively, cytosolic localization, and discuss the major advantages and drawbacks of each method. We critically evaluate methods of measuring "cell penetration" that do not adequately distinguish total cellular uptake and cytosolic localization, which often lead to inaccurate interpretations of a molecule's cytosolic localization. Finally, we summarize the properties and components of each method, including the main caveats of each, to allow for informed decisions about method selection for specific applications. When applied correctly and interpreted carefully, methods for quantifying cytosolic localization offer valuable insight into the bioactivity of biomolecules and potentially the prospects for their eventual development into therapeutics.
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Affiliation(s)
- Kirsten Deprey
- Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155, United States
| | - Lukas Becker
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Joshua Kritzer
- Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155, United States
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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Ivanova R, Benton DCH, Munye MM, Rangseesorranan S, Hart SL, Moss GWJ. A Nanosensor Toolbox for Rapid, Label-Free Measurement of Airway Surface Liquid and Epithelial Cell Function. ACS APPLIED MATERIALS & INTERFACES 2019; 11:8731-8739. [PMID: 30648848 DOI: 10.1021/acsami.8b14122] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ciliated lung epithelial cells and the airway surface liquid (ASL) comprise one of the body's most important protective systems. This system is finely tuned, and perturbations to ASL rheology, ASL depth, ASL pH, the transepithelial potential, and the cilia beat frequency are all associated with disease pathology. Further, these apparently distinct properties interact with each other in a complex manner. For example, changes in ASL rheology can result from altered mucin secretion, changes in ASL pH, or changes in ASL depth. Thus, one of the great challenges in trying to understand airway pathology is that the properties of the ASL/epithelial cell system need to be assessed near-simultaneously and without perturbing the sample. Here, we show that nanosensor probes mounted on a scanning ion conductance microscope make this possible for the first time, without any need for labeling. We also demonstrate that ASL from senescence-retarded human bronchial epithelial cells retains its native properties. Our results demonstrate that by using a nanosensor approach, it is possible to pursue faster, more accurate, more coherent, and more informative studies of ASL and airway epithelia in health and disease.
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29
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Zhao Z, Leonard KC, Boika A. Hot-Tip Scanning Electrochemical Microscopy: Theory and Experiments Under Positive and Negative Feedback Conditions. Anal Chem 2019; 91:2970-2977. [DOI: 10.1021/acs.analchem.8b05192] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhiling Zhao
- Department of Chemistry, The University of Akron, Akron, Ohio 44325, United States
| | - Kevin C. Leonard
- Department of Chemical & Petroleum Engineering, Center for Environmentally Beneficial Catalysis, The University of Kansas, Lawrence, Kansas 66045, United States
| | - Aliaksei Boika
- Department of Chemistry, The University of Akron, Akron, Ohio 44325, United States
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30
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Filice FP, Ding Z. Analysing single live cells by scanning electrochemical microscopy. Analyst 2019; 144:738-752. [DOI: 10.1039/c8an01490f] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Scanning electrochemical microscopy (SECM) offers single live cell activities along its topography toward cellular physiology and pathology.
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Affiliation(s)
- Fraser P. Filice
- Department of Chemistry
- The University of Western Ontario
- London
- Canada
| | - Zhifeng Ding
- Department of Chemistry
- The University of Western Ontario
- London
- Canada
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31
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Bentley CL, Edmondson J, Meloni GN, Perry D, Shkirskiy V, Unwin PR. Nanoscale Electrochemical Mapping. Anal Chem 2018; 91:84-108. [PMID: 30500157 DOI: 10.1021/acs.analchem.8b05235] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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32
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Voci S, Goudeau B, Valenti G, Lesch A, Jović M, Rapino S, Paolucci F, Arbault S, Sojic N. Surface-Confined Electrochemiluminescence Microscopy of Cell Membranes. J Am Chem Soc 2018; 140:14753-14760. [PMID: 30336008 DOI: 10.1021/jacs.8b08080] [Citation(s) in RCA: 194] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Herein is reported a surface-confined microscopy based on electrochemiluminescence (ECL) that allows to image the plasma membrane of single cells at the interface with an electrode. By analyzing photoluminescence (PL), ECL and AFM images of mammalian CHO cells, we demonstrate that, in contrast to the wide-field fluorescence, ECL emission is confined to the immediate vicinity of the electrode surface and only the basal membrane of the cell becomes luminescent. The resulting ECL microscopy reveals details that are not resolved by classic fluorescence microscopy, without any light irradiation and specific setup. The thickness of the ECL-emitting regions is ∼500 nm due to the unique ECL mechanism that involves short-lifetime electrogenerated radicals. In addition, the reported ECL microscopy is a dynamic technique that reflects the transport properties through the cell membranes and not only the specific labeling of the membranes. Finally, disposable transparent carbon nanotube (CNT)-based electrodes inkjet-printed on classic microscope glass coverslips were used to image cells in both reflection and transmission configurations. Therefore, our approach opens new avenues for ECL as a surface-confined microscopy to develop single cell assays and to image the dynamics of biological entities in cells or in membranes.
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Affiliation(s)
- Silvia Voci
- University of Bordeaux , Bordeaux INP, ISM, UMR CNRS 5255 , 33607 Pessac , France
| | - Bertrand Goudeau
- University of Bordeaux , Bordeaux INP, ISM, UMR CNRS 5255 , 33607 Pessac , France
| | - Giovanni Valenti
- Department of Chemistry "G. Ciamician" , University of Bologna , Via Selmi 2 , 40126 Bologna , Italy
| | - Andreas Lesch
- Laboratory of Physical and Analytical Electrochemistry , EPFL Valais Wallis , Rue de l'Industrie 17, CP 440 , CH-1951 Sion , Switzerland
| | - Milica Jović
- Laboratory of Physical and Analytical Electrochemistry , EPFL Valais Wallis , Rue de l'Industrie 17, CP 440 , CH-1951 Sion , Switzerland
| | - Stefania Rapino
- Department of Chemistry "G. Ciamician" , University of Bologna , Via Selmi 2 , 40126 Bologna , Italy
| | - Francesco Paolucci
- Department of Chemistry "G. Ciamician" , University of Bologna , Via Selmi 2 , 40126 Bologna , Italy
| | - Stéphane Arbault
- University of Bordeaux , Bordeaux INP, ISM, UMR CNRS 5255 , 33607 Pessac , France
| | - Neso Sojic
- University of Bordeaux , Bordeaux INP, ISM, UMR CNRS 5255 , 33607 Pessac , France
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33
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Neves MMPDS, Martín-Yerga D. Advanced Nanoscale Approaches to Single-(Bio)entity Sensing and Imaging. BIOSENSORS 2018; 8:E100. [PMID: 30373209 PMCID: PMC6316691 DOI: 10.3390/bios8040100] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 10/11/2018] [Accepted: 10/23/2018] [Indexed: 01/01/2023]
Abstract
Individual (bio)chemical entities could show a very heterogeneous behaviour under the same conditions that could be relevant in many biological processes of significance in the life sciences. Conventional detection approaches are only able to detect the average response of an ensemble of entities and assume that all entities are identical. From this perspective, important information about the heterogeneities or rare (stochastic) events happening in individual entities would remain unseen. Some nanoscale tools present interesting physicochemical properties that enable the possibility to detect systems at the single-entity level, acquiring richer information than conventional methods. In this review, we introduce the foundations and the latest advances of several nanoscale approaches to sensing and imaging individual (bio)entities using nanoprobes, nanopores, nanoimpacts, nanoplasmonics and nanomachines. Several (bio)entities such as cells, proteins, nucleic acids, vesicles and viruses are specifically considered. These nanoscale approaches provide a wide and complete toolbox for the study of many biological systems at the single-entity level.
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Affiliation(s)
| | - Daniel Martín-Yerga
- Department of Chemical Engineering, KTH Royal Institute of Technology, 100-44 Stockholm, Sweden.
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Affiliation(s)
- Pieter E. Oomen
- University of Gothenburg, Department of Chemistry and Molecular Biology, Gothenburg 41296, Sweden
| | - Mohaddeseh A. Aref
- University of Gothenburg, Department of Chemistry and Molecular Biology, Gothenburg 41296, Sweden
| | - Ibrahim Kaya
- University of Gothenburg, Department of Chemistry and Molecular Biology, Gothenburg 41296, Sweden
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal Hospital, House V3, 43180 Mölndal, Sweden
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Laboratory, University of Gothenburg and Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Nhu T. N. Phan
- University of Gothenburg, Department of Chemistry and Molecular Biology, Gothenburg 41296, Sweden
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Laboratory, University of Gothenburg and Chalmers University of Technology, Gothenburg 41296, Sweden
- University of Göttingen Medical Center, Institute of Neuro- and Sensory Physiology, Göttingen 37073, Germany
| | - Andrew G. Ewing
- University of Gothenburg, Department of Chemistry and Molecular Biology, Gothenburg 41296, Sweden
- The Gothenburg Imaging Mass Spectrometry (Go:IMS) Laboratory, University of Gothenburg and Chalmers University of Technology, Gothenburg 41296, Sweden
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35
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Abstract
A concentration gradient driven imaging mechanism is described for scanning ion conductance microscopy (SICM). Two different solution phases, one filling a double-barrel pipet and one in the bath, are used to afford probe control and imaging under nonstandard SICM conditions. Under these conditions, solutions with no added electrolyte can be utilized as the bath solution. Further, both positive and negative feedback modes are exhibited as the probe approaches the surface. We term this method biphasic-SICM (BP-SICM). Technical details of implementing BP-SICM and operational principles are described herein.
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Affiliation(s)
- Myunghoon Choi
- Department of Chemistry , Indiana University , 800 E. Kirkwood Avenue , Bloomington , Indiana 47405 , United States
| | - Lane A Baker
- Department of Chemistry , Indiana University , 800 E. Kirkwood Avenue , Bloomington , Indiana 47405 , United States
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36
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Conzuelo F, Schulte A, Schuhmann W. Biological imaging with scanning electrochemical microscopy. Proc Math Phys Eng Sci 2018; 474:20180409. [PMID: 30839832 PMCID: PMC6237495 DOI: 10.1098/rspa.2018.0409] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Accepted: 09/04/2018] [Indexed: 12/27/2022] Open
Abstract
Scanning electrochemical microscopy (SECM) is a powerful and versatile technique for visualizing the local electrochemical activity of a surface as an ultramicroelectrode tip is moved towards or over a sample of interest using precise positioning systems. In comparison with other scanning probe techniques, SECM not only enables topographical surface mapping but also gathers chemical information with high spatial resolution. Considerable progress has been made in the analysis of biological samples, including living cells and immobilized biomacromolecules such as enzymes, antibodies and DNA fragments. Moreover, combinations of SECM with comple-mentary analytical tools broadened its applicability and facilitated multi-functional analysis with extended life science capabilities. The aim of this review is to present a brief topical overview on recent applications of biological SECM, with particular emphasis on important technical improvements of this surface imaging technique, recommended applications and future trends.
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Affiliation(s)
- Felipe Conzuelo
- Analytical Chemistry—Center for Electrochemical Sciences (CES), Faculty for Chemistry and Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum, Germany
| | - Albert Schulte
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong 21210, Thailand
| | - Wolfgang Schuhmann
- Analytical Chemistry—Center for Electrochemical Sciences (CES), Faculty for Chemistry and Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum, Germany
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37
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Wong Su S, Chieng A, Parres-Gold J, Chang M, Wang Y. Real-time determination of aggregated alpha-synuclein induced membrane disruption at neuroblastoma cells using scanning ion conductance microscopy. Faraday Discuss 2018; 210:131-143. [PMID: 29974096 PMCID: PMC6177297 DOI: 10.1039/c8fd00059j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Parkinson's disease (PD) is recognized as the second most common neurodegenerative disorder and has affected approximately one million people in the United States alone. A large body of evidence has suggested that deposition of aggregated alpha-synuclein (α-Syn), a brain protein abundant near presynaptic termini, in intracellular protein inclusions (Lewy bodies) results in neuronal cell damage and ultimately contributes to the progression of PD. However, the exact mechanism is still unclear. One hypothesis is that α-Syn aggregates disrupt the cell membrane's integrity, eventually leading to cell death. We used scanning ion conductance microscopy (SICM) to monitor the morphological changes of SH-SY5Y neuroblastoma cells and observed dramatic disruption of the cell membrane after adding α-Syn aggregates to the culturing media. This work demonstrates that SICM can be applied as a new approach to studying the cytotoxicity of α-Syn aggregates.
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Affiliation(s)
- Stephanie Wong Su
- Department of Chemistry and Biochemistry, California State University Los Angeles, 5151 State University Dr., Los Angeles, CA 90032, USA.
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38
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Huang L, Li Z, Lou Y, Cao F, Zhang D, Li X. Recent Advances in Scanning Electrochemical Microscopy for Biological Applications. MATERIALS (BASEL, SWITZERLAND) 2018; 11:E1389. [PMID: 30096895 PMCID: PMC6119995 DOI: 10.3390/ma11081389] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/24/2018] [Accepted: 07/28/2018] [Indexed: 12/17/2022]
Abstract
Scanning electrochemical microscopy (SECM) is a chemical microscopy technique with high spatial resolution for imaging sample topography and mapping specific chemical species in liquid environments. With the development of smaller, more sensitive ultramicroelectrodes (UMEs) and more precise computer-controlled measurements, SECM has been widely used to study biological systems over the past three decades. Recent methodological breakthroughs have popularized SECM as a tool for investigating molecular-level chemical reactions. The most common applications include monitoring and analyzing the biological processes associated with enzymatic activity and DNA, and the physiological activity of living cells and other microorganisms. The present article first introduces the basic principles of SECM, followed by an updated review of the applications of SECM in biological studies on enzymes, DNA, proteins, and living cells. Particularly, the potential of SECM for investigating bacterial and biofilm activities is discussed.
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Affiliation(s)
- Luyao Huang
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
| | - Ziyu Li
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
| | - Yuntian Lou
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
| | - Fahe Cao
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
| | - Dawei Zhang
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
| | - Xiaogang Li
- Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
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39
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Zhang S, Li M, Su B, Shao Y. Fabrication and Use of Nanopipettes in Chemical Analysis. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2018; 11:265-286. [PMID: 29894227 DOI: 10.1146/annurev-anchem-061417-125840] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This review summarizes progress in the fabrication, modification, characterization, and applications of nanopipettes since 2010. A brief history of nanopipettes is introduced, and the details of fabrication, modification, and characterization of nanopipettes are provided. Applications of nanopipettes in chemical analysis are the focus in several cases, including recent progress in imaging; in the study of single molecules, single nanoparticles, and single cells; in fundamental investigations of charge transfer (ion and electron) reactions at liquid/liquid interfaces; and as hyphenated techniques combined with other methods to study the mechanisms of complicated electrochemical reactions and to conduct bioanalysis.
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Affiliation(s)
- Shudong Zhang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China;
| | - Mingzhi Li
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China;
| | - Bin Su
- Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou 310058, China;
| | - Yuanhua Shao
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China;
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40
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Bentley CL, Perry D, Unwin PR. Stability and Placement of Ag/AgCl Quasi-Reference Counter Electrodes in Confined Electrochemical Cells. Anal Chem 2018; 90:7700-7707. [PMID: 29808685 DOI: 10.1021/acs.analchem.8b01588] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Nanoelectrochemistry is an important and growing branch of electrochemistry that encompasses a number of key research areas, including (electro)catalysis, energy storage, biomedical/environmental sensing, and electrochemical imaging. Nanoscale electrochemical measurements are often performed in confined environments over prolonged experimental time scales with nonisolated quasi-reference counter electrodes (QRCEs) in a simplified two-electrode format. Herein, we consider the stability of commonly used Ag/AgCl QRCEs, comprising an AgCl-coated wire, in a nanopipet configuration, which simulates the confined electrochemical cell arrangement commonly encountered in nanoelectrochemical systems. Ag/AgCl QRCEs possess a very stable reference potential even when used immediately after preparation and, when deployed in Cl- free electrolyte media (e.g., 0.1 M HClO4) in the scanning ion conductance microscopy (SICM) format, drift by only ca. 1 mV h-1 on the several hours time scale. Furthermore, contrary to some previous reports, when employed in a scanning electrochemical cell microscopy (SECCM) format (meniscus contact with a working electrode surface), Ag/AgCl QRCEs do not cause fouling of the surface (i.e., with soluble redox byproducts, such as Ag+) on at least the 6 h time scale, as long as suitable precautions with respect to electrode handling and placement within the nanopipet are observed. These experimental observations are validated through finite element method (FEM) simulations, which consider Ag+ transport within a nanopipet probe in the SECCM and SICM configurations. These results confirm that Ag/AgCl is a stable and robust QRCE in confined electrochemical environments, such as in nanopipets used in SICM, for nanopore measurements, for printing and patterning, and in SECCM, justifying the widespread use of this electrode in the field of nanoelectrochemistry and beyond.
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Affiliation(s)
- Cameron L Bentley
- Department of Chemistry , University of Warwick , Coventry CV4 7AL , United Kingdom
| | - David Perry
- Department of Chemistry , University of Warwick , Coventry CV4 7AL , United Kingdom
| | - Patrick R Unwin
- Department of Chemistry , University of Warwick , Coventry CV4 7AL , United Kingdom
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41
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Advances and Perspectives in Chemical Imaging in Cellular Environments Using Electrochemical Methods. CHEMOSENSORS 2018. [DOI: 10.3390/chemosensors6020024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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42
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Lin TE, Rapino S, Girault HH, Lesch A. Electrochemical imaging of cells and tissues. Chem Sci 2018; 9:4546-4554. [PMID: 29899947 PMCID: PMC5969511 DOI: 10.1039/c8sc01035h] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 04/09/2018] [Indexed: 01/10/2023] Open
Abstract
This minireview summarizes the recent achievements of electrochemical imaging platforms to map cellular functions in biological specimens using electrochemical scanning nano/micro-probe microscopy and 2D chips containing microelectrode arrays.
The technological and experimental progress in electrochemical imaging of biological specimens is discussed with a view on potential applications for skin cancer diagnostics, reproductive medicine and microbial testing. The electrochemical analysis of single cell activity inside cell cultures, 3D cellular aggregates and microtissues is based on the selective detection of electroactive species involved in biological functions. Electrochemical imaging strategies, based on nano/micrometric probes scanning over the sample and sensor array chips, respectively, can be made sensitive and selective without being affected by optical interference as many other microscopy techniques. The recent developments in microfabrication, electronics and cell culturing/tissue engineering have evolved in affordable and fast-sampling electrochemical imaging platforms. We believe that the topics discussed herein demonstrate the applicability of electrochemical imaging devices in many areas related to cellular functions.
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Affiliation(s)
- Tzu-En Lin
- Laboratory of Physical and Analytical Electrochemistry (LEPA) , École Polytechnique Fédéderale de Lausanne , EPFL Valais Valais , Rue de l'Industrie 17 , CP 440 , 1951 Sion , Switzerland .
| | - Stefania Rapino
- Chemistry Department "Giacomo Ciamician" , University of Bologna , Via Selmi 2 , 40126 Bologna , Italy
| | - Hubert H Girault
- Laboratory of Physical and Analytical Electrochemistry (LEPA) , École Polytechnique Fédéderale de Lausanne , EPFL Valais Valais , Rue de l'Industrie 17 , CP 440 , 1951 Sion , Switzerland .
| | - Andreas Lesch
- Laboratory of Physical and Analytical Electrochemistry (LEPA) , École Polytechnique Fédéderale de Lausanne , EPFL Valais Valais , Rue de l'Industrie 17 , CP 440 , 1951 Sion , Switzerland .
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43
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Schierbaum N, Hack M, Betz O, Schäffer TE. Macro-SICM: A Scanning Ion Conductance Microscope for Large-Range Imaging. Anal Chem 2018; 90:5048-5054. [PMID: 29569436 DOI: 10.1021/acs.analchem.7b04764] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The scanning ion conductance microscope (SICM) is a versatile, high-resolution imaging technique that uses an electrolyte-filled nanopipet as a probe. Its noncontact imaging principle makes the SICM uniquely suited for the investigation of soft and delicate surface structures in a liquid environment. The SICM has found an ever-increasing number of applications in chemistry, physics, and biology. However, a drawback of conventional SICMs is their relatively small scan range (typically 100 μm × 100 μm in the lateral and 10 μm in the vertical direction). We have developed a Macro-SICM with an exceedingly large scan range of 25 mm × 25 mm in the lateral and 0.25 mm in the vertical direction. We demonstrate the high versatility of the Macro-SICM by imaging at different length scales: from centimeters (fingerprint, coin) to millimeters (bovine tongue tissue, insect wing) to micrometers (cellular extensions). We applied the Macro-SICM to the study of collective cell migration in epithelial wound healing.
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44
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Zhu Z, Ye Z, Zhang Q, Zhang J, Cao F. Novel dual Pt-Pt/IrO ultramicroelectrode for pH imaging using SECM in both potentiometric and amperometric modes. Electrochem commun 2018. [DOI: 10.1016/j.elecom.2018.01.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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45
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Zhang J, Zhou J, Pan R, Jiang D, Burgess JD, Chen HY. New Frontiers and Challenges for Single-Cell Electrochemical Analysis. ACS Sens 2018; 3:242-250. [PMID: 29276834 DOI: 10.1021/acssensors.7b00711] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Previous measurements of cell populations might obscure many important cellular differences, and new strategies for single-cell analyses are urgently needed to re-examine these fundamental biological principles for better diagnosis and treatment of diseases. Electrochemistry is a robust technique for the analysis of single living cells that has the advantages of minor interruption of cellular activity and provides the capability of high spatiotemporal resolution. The achievements of the past 30 years have revealed significant information about the exocytotic events of single cells to elucidate the mechanisms of cellular activity. Currently, the rapid developments of micro/nanofabrication and optoelectronic technologies drive the development of multifunctional electrodes and novel electrochemical approaches with higher resolution for single cells. In this Perspective, three new frontiers in this field, namely, electrochemical microscopy, intracellular analysis, and single-cell analysis in a biological system (i.e., neocortex and retina), are reviewed. The unique features and remaining challenges of these techniques are discussed.
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Affiliation(s)
- Jingjing Zhang
- The
State Key Laboratory of Analytical Chemistry for Life Science, School
of Chemistry and Chemical Engineering, Nanjing University, Jiangsu 210093, China
| | - Junyu Zhou
- The
State Key Laboratory of Analytical Chemistry for Life Science, School
of Chemistry and Chemical Engineering, Nanjing University, Jiangsu 210093, China
| | - Rongrong Pan
- The
State Key Laboratory of Analytical Chemistry for Life Science, School
of Chemistry and Chemical Engineering, Nanjing University, Jiangsu 210093, China
| | - Dechen Jiang
- The
State Key Laboratory of Analytical Chemistry for Life Science, School
of Chemistry and Chemical Engineering, Nanjing University, Jiangsu 210093, China
| | - James D. Burgess
- Department
of Medical Laboratory, Imaging, and Radiologic Sciences, College of
Allied Health Sciences, Augusta University, Augusta, Georgia 30912, United States
| | - Hong-Yuan Chen
- The
State Key Laboratory of Analytical Chemistry for Life Science, School
of Chemistry and Chemical Engineering, Nanjing University, Jiangsu 210093, China
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46
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Takahashi Y, Ida H, Matsumae Y, Komaki H, Zhou Y, Kumatani A, Kanzaki M, Shiku H, Matsue T. 3D electrochemical and ion current imaging using scanning electrochemical-scanning ion conductance microscopy. Phys Chem Chem Phys 2018; 19:26728-26733. [PMID: 28951914 DOI: 10.1039/c7cp05157c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Local cell-membrane permeability and ionic strength are important factors for maintaining the functions of cells. Here, we measured the spatial electrochemical and ion concentration profile near the sample surface with nanoscale resolution using scanning electrochemical microscopy (SECM) combined with scanning ion-conductance microscopy (SICM). The ion current feedback system is an effective way to control probe-sample distance without contact and monitor the kinetic effect of mediator regeneration and the chemical concentration profile. For demonstrating 3D electrochemical and ion concentration mapping, we evaluated the reaction rate of electrochemical mediator regeneration on an unbiased conductor and visualized inhomogeneous permeability and the ion concentration 3D profile on a single fixed adipocyte cell surface.
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Affiliation(s)
- Yasufumi Takahashi
- WPI-Advanced Institute for Materials Research, Tohoku University, 980-8577, Japan.
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47
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Bentley CL, Unwin PR. Nanoscale electrochemical movies and synchronous topographical mapping of electrocatalytic materials. Faraday Discuss 2018; 210:365-379. [PMID: 29999075 DOI: 10.1039/c8fd00028j] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Techniques in the scanning electrochemical probe microscopy (SEPM) family have shown great promise for resolving nanoscale structure-function (e.g., catalytic activity) at complex (electro)chemical interfaces, which is a long-term aspiration in (electro)materials science. In this work, we explore how a simple meniscus imaging probe, based on an easily-fabricated, single-channeled nanopipette (inner diameter ≈ 30 nm) can be deployed in the scanning electrochemical cell microscopy (SECCM) platform as a fast, versatile and robust method for the direct, synchronous electrochemical/topographical imaging of electrocatalytic materials at the nanoscale. Topographical and voltammetric data are acquired synchronously at a spatial resolution of 50 nm to construct maps that resolve particular surface features on the sub-10 nm scale and create electrochemical activity movies composed of hundreds of potential-resolved images on the minutes timescale. Using the hydrogen evolution reaction (HER) at molybdenite (MoS2) as an exemplar system, the experimental parameters critical to achieving a robust scanning protocol (e.g., approach voltage, reference potential calibration) with high resolution (e.g., hopping distance) and optimal scan times (e.g., voltammetric scan rate, approach rate etc.) are considered and discussed. Furthermore, sub-nanoentity reactivity mapping is demonstrated with glassy carbon (GC) supported single-crystalline {111}-oriented two-dimensional Au nanocrystals (AuNCs), which exhibit uniform catalytic activity at the single-entity and sub-single entity level. The approach outlined herein signposts a future in (electro)materials science in which the activity of electroactive nanomaterials can be viewed directly and related to structure through electrochemical movies, revealing active sites unambiguously.
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Affiliation(s)
- Cameron L Bentley
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.
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48
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Bentley CL, Kang M, Unwin PR. Nanoscale Structure Dynamics within Electrocatalytic Materials. J Am Chem Soc 2017; 139:16813-16821. [PMID: 29058886 DOI: 10.1021/jacs.7b09355] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Electrochemical interfaces used for sensing, (electro)catalysis, and energy storage are usually nanostructured to expose particular surface sites, but probing the intrinsic activity of these sites is often beyond current experimental capability. Herein, it is demonstrated how a simple meniscus imaging probe of just 30 nm in size can be deployed for direct electrochemical and topographical imaging of electrocatalytic materials at the nanoscale. Spatially resolved topographical and electrochemical data are collected synchronously to create topographical images in which step-height features as small as 2 nm are easily resolved and potential-resolved electrochemical activity movies composed of hundreds of images are obtained in a matter of minutes. The technique has been benchmarked by investigating the hydrogen evolution reaction on molybdenum disulfide, where it is shown that the basal plane possesses uniform activity, while surface defects (i.e., few to multilayer step edges) give rise to a morphology-dependent (i.e., height-dependent) enhancement in catalytic activity. The technique was then used to investigate the electro-oxidation of hydrazine at the surface of electrodeposited Au nanoparticles (AuNPs) supported on glassy carbon, where subnanoentity (i.e., sub-AuNP) reactivity mapping has been demonstrated. We show, for the first time, that electrochemical reaction rates vary significantly across an individual AuNP surface and that these single entities cannot be considered as uniformly active. The work herein provides a road map for future studies in electrochemical science, in which the activity of nanostructured materials can be viewed as quantitative movies, readily obtained, to reveal active sites directly and unambiguously.
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Affiliation(s)
- Cameron L Bentley
- Department of Chemistry, University of Warwick , Coventry CV4 7AL, U.K
| | - Minkyung Kang
- 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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Aebersold MJ, Dermutz H, Demkó L, Cogollo JFS, Lin SC, Burchert C, Schneider M, Ling D, Forró C, Han H, Zambelli T, Vörös J. Local Chemical Stimulation of Neurons with the Fluidic Force Microscope (FluidFM). Chemphyschem 2017; 19:1234-1244. [DOI: 10.1002/cphc.201700780] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 10/06/2017] [Indexed: 01/06/2023]
Affiliation(s)
- Mathias J. Aebersold
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Harald Dermutz
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - László Demkó
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - José F. Saenz Cogollo
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Shiang-Chi Lin
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Conrad Burchert
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Moritz Schneider
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Doris Ling
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Csaba Forró
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Hana Han
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Tomaso Zambelli
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - János Vörös
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
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Perry D, Page A, Chen B, Frenguelli BG, Unwin PR. Differential-Concentration Scanning Ion Conductance Microscopy. Anal Chem 2017; 89:12458-12465. [DOI: 10.1021/acs.analchem.7b03543] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- David Perry
- Department
of Chemistry, ‡MOAC Doctoral Training Centre, §School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Ashley Page
- Department
of Chemistry, ‡MOAC Doctoral Training Centre, §School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Baoping Chen
- Department
of Chemistry, ‡MOAC Doctoral Training Centre, §School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Bruno G. Frenguelli
- Department
of Chemistry, ‡MOAC Doctoral Training Centre, §School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Patrick R. Unwin
- Department
of Chemistry, ‡MOAC Doctoral Training Centre, §School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
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