1
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Perrodin P, Sella C, Thouin L. Electrochemical Generation of Steady-State Linear Concentration Gradients within Microfluidic Channels Perpendicular to the Flow Field. Anal Chem 2020; 92:7699-7707. [DOI: 10.1021/acs.analchem.0c00645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Pierre Perrodin
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Catherine Sella
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Laurent Thouin
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
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2
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Kostiuchenko ZA, Lemay SG. Quasi-One-Dimensional Generator-Collector Electrochemistry in Nanochannels. Anal Chem 2020; 92:2847-2852. [PMID: 31934747 PMCID: PMC7003156 DOI: 10.1021/acs.analchem.9b05396] [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] [Indexed: 11/28/2022]
Abstract
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Mass transport in
fluidic channels under conditions of pressure-driven
flow is controlled by a combination of convection and diffusion. For
electrochemical measurements the height of a channel is typically
of the same order of magnitude as the electrode dimensions, resulting
in complex two- or three- dimensional concentration distributions.
Electrochemical nanofluidic devices, however, can have such a low
height-to-length ratio that they can effectively be considered as
one-dimensional. This greatly simplifies the modeling and quantitative
interpretation of analytical measurements. Here we study mass transport
in nanochannels using electrodes in a generator-collector configuration.
The flux of redox molecules is monitored amperometrically. We observe
the transition from diffusion-dominated to convection-dominated transport
by varying both the flow velocity and the distance between the electrodes.
These results are described quantitatively by the one-dimensional
Nernst–Planck equation for mass transport over the full range
of experimentally accessible parameters.
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Affiliation(s)
- Zinaida A Kostiuchenko
- MESA+ Institute for Nanotechnology and Faculty of Science and Technology , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - Serge G Lemay
- MESA+ Institute for Nanotechnology and Faculty of Science and Technology , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
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3
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Abadie T, Sella C, Perrodin P, Thouin L. Electrochemical Generation and Detection of Transient Concentration Gradients in Microfluidic Channels. Theoretical and Experimental Investigations. Front Chem 2019; 7:704. [PMID: 31709233 PMCID: PMC6822297 DOI: 10.3389/fchem.2019.00704] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 10/08/2019] [Indexed: 12/21/2022] Open
Abstract
Transient concentration gradients generated and detected electrochemically in continuous flow microchannels were investigated by numerical simulations and amperometric measurements. Operating conditions including device geometry and hydrodynamic regime were theoretically delineated for producing gradients of various profiles with tunable characteristics. Experiments were carried out with microfluidic devices incorporating a dual-channel-electrode configuration. Under these conditions, high electrochemical performance was achieved both to generate concentration gradients and to monitor their dynamics along linear microchannels. Good agreement was observed between simulated and experimental data validating predictions between gradient properties and generation conditions. These results demonstrated the capability of electrochemical microdevices to produce in situ tunable concentration gradients with real-time monitoring. This approach is versatile for the active control in microfluidics of microenvironments or chemical gradients with high spatiotemporal resolution.
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Affiliation(s)
| | | | | | - Laurent Thouin
- PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, Paris, France
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4
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Effect of Electrode Shape and Flow Conditions on the Electrochemical Detection with Band Microelectrodes. SENSORS 2018; 18:s18103196. [PMID: 30248945 PMCID: PMC6210975 DOI: 10.3390/s18103196] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/10/2018] [Accepted: 09/18/2018] [Indexed: 01/10/2023]
Abstract
In this work, we report the analysis of the electrochemical detection of electroactive species with band microelectrodes that operate under controlled convection. The study focuses on the determination of the collection efficiency of the analyte as a function of inlet flow velocity and microband geometry (inlaid, bumped and recessed), also providing a straightforward method for the theoretical determination of the lower detection limit. The analysis has been carried out by simulating the dimensionless mass transport with the finite element method, delivering the stationary limiting current density. Simulations have been performed on systems consisting of single and double band electrodes to investigate the trail effect on the electrochemical detection. We show that the obtained dimensionless results can be easily turned into dimensional data, providing a tool for the design of devices. The proposed method is general and can easily be extended to systems with different geometry.
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5
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Anderson MJ, Crooks RM. Microfluidic Surface Titrations of Electroactive Thin Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:7053-7061. [PMID: 28665618 DOI: 10.1021/acs.langmuir.7b01542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report the use of microfluidic surface titrations (MSTs) for studying electroactive self-assembled monolayers (eSAMs) and other thin films. The technique of MST utilizes a microfluidic generation-collection dual channel electrode (DCE) configuration to quantify the charge associated with electroactive thin films that might or might not be in direct contact with an electrode surface. This technique allows for quantitative measurement of surface coverages, Γ, as low as 30 pmol cm-2 for electrodeposited Cu thin films. Additionally, we show that it is possible to quantify Γ for ferrocene (Fc)-terminated alkylthiols in mixed-monolayer eSAMs. Interestingly, MSTs sometimes reveal a two-fold higher eSAM concentration compared to direct electrochemical measurements. This finding suggests that in these instances not all the constituent Fc-moieties of the eSAM are in sufficiently close proximity to the surface to be addressable via direct electrochemistry.
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Affiliation(s)
- Morgan J Anderson
- Department of Chemistry, The University of Texas at Austin , 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
| | - Richard M Crooks
- Department of Chemistry, The University of Texas at Austin , 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
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6
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Kundys M, Nejbauer M, Jönsson-Niedziolka M, Adamiak W. Generation–Collection Electrochemistry Inside a Rotating Droplet. Anal Chem 2017; 89:8057-8063. [DOI: 10.1021/acs.analchem.7b01533] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Magdalena Kundys
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Michal Nejbauer
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | | | - Wojciech Adamiak
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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7
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Fanavoll EV, Harrington DA, Sunde S, Singh G, Seland F. A microfluidic electrochemical cell with integrated PdH reference electrode for high current experiments. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2016.11.147] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Nguyen VQ, Schaming D, Tran DL, Lacroix JC. Ordered Nanoporous Thin Films by Nanosphere Lithography and Diazonium Electroreduction: Simple Elaboration of Ultra-Micro-Electrode Arrays. ChemElectroChem 2016. [DOI: 10.1002/celc.201600420] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Van-Quynh Nguyen
- Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS; 15 rue Jean-Antoine de Baïf 75205 Paris Cedex 13 France
- Department of Advanced Materials Science and Nanotechnology; University of Science and Technology of Hanoi (USTH); 18 Hoang Quoc Viet Hanoi Vietnam
| | - Delphine Schaming
- Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS; 15 rue Jean-Antoine de Baïf 75205 Paris Cedex 13 France
| | - Dai Lam Tran
- Graduate University of Science and Technology; Vietnam Academy of Science and Technology; 18 Hoang Quoc Viet Hanoi Vietnam
| | - Jean-Christophe Lacroix
- Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS; 15 rue Jean-Antoine de Baïf 75205 Paris Cedex 13 France
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9
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Understanding Mass Transport at Channel Microband Electrodes: Influence of Confined Space under Stagnant Conditions. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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10
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Interactions between Human Antibodies and Synthetic Conformational Peptide Epitopes: Innovative Approach for Electrochemical Detection of Biomarkers of Multiple Sclerosis at Platinum Electrodes. Electrochim Acta 2015. [DOI: 10.1016/j.electacta.2015.07.158] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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Lewis GEM, Gross AJ, Kasprzyk-Hordern B, Lubben AT, Marken F. Feedback-amplified electrochemical dual-plate boron-doped diamond microtrench detector for flow injection analysis. Electrophoresis 2015; 36:1866-71. [PMID: 25735831 PMCID: PMC4687414 DOI: 10.1002/elps.201500017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 01/30/2015] [Accepted: 01/30/2015] [Indexed: 11/19/2022]
Abstract
An electrochemical flow cell with a boron‐doped diamond dual‐plate microtrench electrode has been developed and demonstrated for hydroquinone flow injection electroanalysis in phosphate buffer pH 7. Using the electrochemical generator‐collector feedback detector improves the sensitivity by one order of magnitude (when compared to a single working electrode detector). The diffusion process is switched from an analyte consuming “external” process to an analyte regenerating “internal” process with benefits in selectivity and sensitivity.
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Affiliation(s)
| | | | | | | | - Frank Marken
- Department of Chemistry, University of Bath, Bath, UK
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12
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Anderson MJ, Crooks RM. High-Efficiency Generation-Collection Microelectrochemical Platform for Interrogating Electroactive Thin Films. Anal Chem 2014; 86:9962-9. [PMID: 25260095 DOI: 10.1021/ac502869j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Morgan J. Anderson
- Department of Chemistry,
Center for Nano- and Molecular Science and Technology, and the Center
for Electrochemistry, The University of Texas at Austin, 105
East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
| | - Richard M. Crooks
- Department of Chemistry,
Center for Nano- and Molecular Science and Technology, and the Center
for Electrochemistry, The University of Texas at Austin, 105
East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
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13
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Renault C, Anderson MJ, Crooks RM. Electrochemistry in hollow-channel paper analytical devices. J Am Chem Soc 2014; 136:4616-23. [PMID: 24635569 DOI: 10.1021/ja4118544] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In the present article we provide a detailed analysis of fundamental electrochemical processes in a new class of paper-based analytical devices (PADs) having hollow channels (HCs). Voltammetry and amperometry were applied under flow and no flow conditions yielding reproducible electrochemical signals that can be described by classical electrochemical theory as well as finite-element simulations. The results shown here provide new and quantitative insights into the flow within HC-PADs. The interesting new result is that despite their remarkable simplicity these HC-PADs exhibit electrochemical and hydrodynamic behavior similar to that of traditional microelectrochemical devices.
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Affiliation(s)
- Christophe Renault
- Department of Chemistry, Center for Nano- and Molecular Science and Technology, The University of Texas at Austin , 105 East 24th Street Stop A5300, Austin, Texas 78712-1224, United States
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14
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Pebay C, Sella C, Thouin L, Amatore C. Mass transport at infinite regular arrays of microband electrodes submitted to natural convection: theory and experiments. Anal Chem 2013; 85:12062-9. [PMID: 24283775 DOI: 10.1021/ac403159j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mass transport at infinite regular arrays of microband electrodes was investigated theoretically and experimentally in unstirred solutions. Even in the absence of forced hydrodynamics, natural convection limits the convection-free domain up to which diffusion layers may expand. Hence, several regimes of mass transport may take place according to the electrode size, gap between electrodes, time scale of the experiment, and amplitude of natural convection. They were identified through simulation by establishing zone diagrams that allowed all relative contributions to mass transport to be delineated. Dynamic and steady-state regimes were compared to those achieved at single microband electrodes. These results were validated experimentally by monitoring the chronoamperometric responses of arrays with different ratios of electrode width to gap distance and by mapping steady-state concentration profiles above their surface through scanning electrochemical microscopy.
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Affiliation(s)
- Cécile Pebay
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 Pasteur, 24 rue Lhomond, 75231 Paris Cedex 05, France
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15
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Oliveira R, Bento F, Sella C, Thouin L, Amatore C. Direct Electroanalytical Method for Alternative Assessment of Global Antioxidant Capacity Using Microchannel Electrodes. Anal Chem 2013; 85:9057-63. [DOI: 10.1021/ac401566w] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Raquel Oliveira
- Centro
de Química, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Fátima Bento
- Centro
de Química, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Catherine Sella
- Département
de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640
PASTEUR, 24 rue Lhomond, 75231 Paris Cedex 05, France
| | - Laurent Thouin
- Département
de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640
PASTEUR, 24 rue Lhomond, 75231 Paris Cedex 05, France
| | - Christian Amatore
- Département
de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640
PASTEUR, 24 rue Lhomond, 75231 Paris Cedex 05, France
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16
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Mathematical modeling of interdigitated electrode arrays in finite electrochemical cells. J Electroanal Chem (Lausanne) 2013. [DOI: 10.1016/j.jelechem.2013.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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17
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18
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Dual electrode micro-channel flow cell for redox titrations: Kinetics and analysis of homogeneous ascorbic acid oxidation. J Electroanal Chem (Lausanne) 2013. [DOI: 10.1016/j.jelechem.2012.12.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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19
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Li Y, Sella C, Lemaître F, Guille Collignon M, Thouin L, Amatore C. Highly Sensitive Platinum-Black Coated Platinum Electrodes for Electrochemical Detection of Hydrogen Peroxide and Nitrite in Microchannel. ELECTROANAL 2013. [DOI: 10.1002/elan.201200456] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Amatore C, Pebay C, Sella C, Thouin L. Mass Transport at Microband Electrodes: Transient, Quasi-Steady-State, and Convective Regimes. Chemphyschem 2012; 13:1562-8. [DOI: 10.1002/cphc.201100942] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/02/2012] [Indexed: 11/09/2022]
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21
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Dumitrescu I, Yancey DF, Crooks RM. Dual-electrode microfluidic cell for characterizing electrocatalysts. LAB ON A CHIP 2012; 12:986-993. [PMID: 22282034 DOI: 10.1039/c2lc21181e] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this paper we introduce a microelectrochemical cell configured for generation-collection experiments and designed primarily for examining the kinetics of electrocatalysts. The heart of the device consists of two, closely spaced, pyrolyzed photoresist microband electrodes enclosed within a microchannel. The cell is suitable for evaluating the efficiency of electrocatalysts under an unprecedented range of conditions. Specifically, compared to the gold-standard rotating ring-disk electrode (RRDE), this device offers four major advantages. First, collection efficiencies of 97% are easily achieved, compared to values of 20-37% that are characteristic of RRDEs. Second, mass transfer coefficients of 0.5 cm s(-1) are accessible for typical redox species, which is significantly higher than RRDEs (up to 0.01 cm s(-1)). Third, we show that the device can operate effectively at temperatures up to 70 °C, which is important for measuring electrochemical kinetics that are relevant to fuel cell catalysts. Finally, much less catalyst and much smaller volumes of electrolyte solution are required to make kinetic measurements using the microelectrochemical device compared to the RRDE. Here, we present the simple procedure used to fabricate the device, fundamental electroanalytical characterization, and electrocatalytic measurements relevant to the oxygen reduction reaction.
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Affiliation(s)
- Ioana Dumitrescu
- Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712-0165, USA
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22
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Amatore C, Lemmer C, Perrodin P, Sella C, Thouin L. Theory and experiments of microelectrodes performing as concentration probes within microfluidic channels with high temporal resolution. Electrochem commun 2011. [DOI: 10.1016/j.elecom.2011.09.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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23
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Scialdone O, Guarisco C, Galia A. Oxidation of organics in water in microfluidic electrochemical reactors: Theoretical model and experiments. Electrochim Acta 2011. [DOI: 10.1016/j.electacta.2011.09.073] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Chen IJ, White IM. High-sensitivity electrochemical enzyme-linked assay on a microfluidic interdigitated microelectrode. Biosens Bioelectron 2011; 26:4375-81. [PMID: 21601441 PMCID: PMC3120925 DOI: 10.1016/j.bios.2011.04.044] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 04/21/2011] [Accepted: 04/25/2011] [Indexed: 11/28/2022]
Abstract
A novel enzyme-linked DNA hybridization assay on an interdigitated array (IDA) microelectrode integrated into a microfluidic channel is demonstrated with sub-nM detection limit. To improve the detection limit as compared to conventional electrochemical biosensors, a recyclable redox product, 4-aminophenol (PAP) is used with an IDA microelectrode. The IDA has a modest and easily fabricated inter-digit spacing of 10 μm, yet we were able to demonstrate 97% recycling efficiency of PAP due to the integration in a microfluidic channel. With a 70 nL sample volume, the characterized detection limit for PAP of 1.0 × 10⁻¹⁰ M is achieved, with a linear dynamic range that extends from 1.0 × 10⁻⁹ to 1.0 × 10⁻⁵ M. This detection limit, which is the lowest reported detection limit for PAP, is due to the increased sensitivity provided by the sample confinement in the microfluidic channel, as well as the increased repeatability due to perfectly static flow in the microchannel and an additional anti-fouling step in the protocol. DNA sequence detection is achieved through a hybridization sandwich of an immobilized complementary probe, the target DNA sequence, and a second complementary probe labeled with β-galactosidase (β-GAL); the β-GAL converts its substrate, 4-aminophenyl-d-galactopyranoside (PAPG), into PAP. In this report we present the lowest reported observed detection limit (1.0 × 10⁻¹⁰ M) for an enzyme-linked DNA hybridization assay using an IDA microelectrode and a redox signaling paradigm. Thus, we have demonstrated highly sensitive detection of a targeted DNA sequence using a low-cost easily fabricated electrochemical biosensor integrated into a microfluidic channel.
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Affiliation(s)
- I-Jane Chen
- Fischell Department of Bioengineering, 2330 Jeong H. Kim Engineering Bldg., University of Maryland, College Park, MD 20742
| | - Ian M. White
- Fischell Department of Bioengineering, 2330 Jeong H. Kim Engineering Bldg., University of Maryland, College Park, MD 20742
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25
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Zhou J, Ren K, Dai W, Zhao Y, Ryan D, Wu H. Pumping-induced perturbation of flow in microfluidic channels and its implications for on-chip cell culture. LAB ON A CHIP 2011; 11:2288-94. [PMID: 21603722 DOI: 10.1039/c0lc00466a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We study the rate of response to changes in the rate of flow and the perturbations in flow in polydimethylsiloxane (PDMS) microfluidic chips that are subjected to several common flow-control systems. We find that the flow rate of liquid delivered from a syringe pump equipped with a glass syringe responds faster to the changes in the conditions of flow than the same liquid delivered from a plastic syringe; and the rate of flow delivered from compressed air responds faster than that from a glass syringe. We discover that the rate of flow that is driven by a syringe pump and regulated by an integrated pneumatic valve responds even faster, but this flow-control method is characterized by large perturbations. We also examine the possible effects of these large perturbations on NIH 3T3 cells in microfluidic channels and find that they could cause the detachment of NIH 3T3 cells in the microchannels.
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Affiliation(s)
- Jianhua Zhou
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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26
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Cutress IJ, Wang Y, Limon-Petersen JG, Dale SE, Rassaei L, Marken F, Compton RG. Dual-microdisk electrodes in transient generator–collector mode: Experiment and theory. J Electroanal Chem (Lausanne) 2011. [DOI: 10.1016/j.jelechem.2011.02.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Amatore C, Lemmer C, Sella C, Thouin L. Channel Microband Chronoamperometry: From Transient to Steady-State Regimes. Anal Chem 2011; 83:4170-7. [DOI: 10.1021/ac2004604] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christian Amatore
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Célia Lemmer
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Catherine Sella
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Laurent Thouin
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
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28
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Vuorema A, Meadows H, Ibrahim NB, Del Campo J, Cortina-Puig M, Vagin MY, Karyakin AA, Sillanpää M, Marken F. Ion Transport Across Liquid|Liquid Interfacial Boundaries Monitored at Generator-Collector Electrodes. ELECTROANAL 2010. [DOI: 10.1002/elan.201000368] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Fortgang P, Amatore C, Maisonhaute E, Schöllhorn B. Microchip for ultrafast voltammetry. Electrochem commun 2010. [DOI: 10.1016/j.elecom.2010.04.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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30
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Cutress IJ, Compton RG. Theory of square, rectangular, and microband electrodes through explicit GPU simulation. J Electroanal Chem (Lausanne) 2010. [DOI: 10.1016/j.jelechem.2010.05.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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31
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Lewis PM, Sheridan LB, Gawley RE, Fritsch I. Signal amplification in a microchannel from redox cycling with varied electroactive configurations of an individually addressable microband electrode array. Anal Chem 2010; 82:1659-68. [PMID: 20108925 PMCID: PMC2857402 DOI: 10.1021/ac901066p] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amperometric detection at microelectrodes in lab-on-a-chip (LOAC) devices lose advantages in signal-to-background ratio, reduced ohmic iR drop, and steady-state signal when volumes are so small that diffusion fields reach the walls before flux becomes fully radial. Redox cycling of electroactive species between multiple, closely spaced microelectrodes offsets that limitation and provides amplification capabilities. A device that integrates a microchannel with an individually addressable microband electrode array has been used to study effects of signal amplification due to redox cycling in a confined, static solution with different configurations and numbers of active generators and collectors. The microfabricated device consists of a 22 microm high, 600 microm wide microchannel containing an array of 50 microm wide, 600 microm long gold microbands, separated by 25 microm gaps, interspersed with an 800 microm wide counter electrode and 400 microm wide passive conductor, with a distant but on-chip 400 microm wide pseudoreference electrode. Investigations involve solutions of potassium chloride electrolyte containing potassium ferrocyanide. Amplification factors were as high as 7.60, even with these microelectrodes of fairly large dimensions (which are generally less expensive, easier, and more reproducible to fabricate), because of the significant role that passive and active (instrumentally induced) redox cycling plays in confined volumes of enclosed microchannels. The studies are useful in optimizing designs for LOAC devices.
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Affiliation(s)
- Penny M. Lewis
- University of Arkansas, Department of Chemistry and Biochemistry, Fayetteville, AR 72701, Tel: (479) 575-6499, Fax: (479) 575-4049,
| | - Leah Bullard Sheridan
- University of Arkansas, Department of Chemistry and Biochemistry, Fayetteville, AR 72701, Tel: (479) 575-6499, Fax: (479) 575-4049,
| | - Robert E. Gawley
- University of Arkansas, Department of Chemistry and Biochemistry, Fayetteville, AR 72701, Tel: (479) 575-6499, Fax: (479) 575-4049,
| | - Ingrid Fritsch
- University of Arkansas, Department of Chemistry and Biochemistry, Fayetteville, AR 72701, Tel: (479) 575-6499, Fax: (479) 575-4049,
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Amatore C, Da Mota N, Sella C, Thouin L. Theory and Experiments of Transport at Channel Microband Electrodes Under Laminar Flow. 3. Electrochemical Detection at Electrode Arrays under Steady State. Anal Chem 2010; 82:2434-40. [DOI: 10.1021/ac902788v] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christian Amatore
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Nicolas Da Mota
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Catherine Sella
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Laurent Thouin
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “Pasteur”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
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33
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Henstridge MC, Wildgoose GG, Compton RG. Generator-collector experiments at a single electrode: exploring the general applicability of this approach by comparing the performance of surface immobilized versus solution phase sensing molecules. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:1340-1346. [PMID: 19746936 DOI: 10.1021/la902418v] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We demonstrate proof-of-concept that generator-collector experiments can be performed at a single macroelectrode and used to determine mechanistic information. The practical advantages of such a system over conventional generator-collector techniques are also outlined. The single-electrode generator-collector technique is applied to study the known mechanism of oxygen reduction in aqueous conditions as a model system. We seek to demonstrate that the single-electrode generator-collector approach is capable of detecting local pH changes, immediately adjacent to the electrode surface during a redox reaction. Experiments are performed using a molecular pH probe attached to the electrode surface. Comparison of experimental data with numerical simulations verifies that the reduction of oxygen at pH 6.8 proceeds via a two-electron, two-proton mechanism. Experiments were also performed with a molecular pH probe dissolved in the electrolyte solution in order to explore the feasibility of this approach, which is potentially applicable to a much wider range of electrochemical systems.
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Affiliation(s)
- Martin C Henstridge
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
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34
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Scialdone O, Guarisco C, Galia A, Filardo G, Silvestri G, Amatore C, Sella C, Thouin L. Anodic abatement of organic pollutants in water in micro reactors. J Electroanal Chem (Lausanne) 2010. [DOI: 10.1016/j.jelechem.2009.10.031] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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35
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Amatore C, Da Mota N, Lemmer C, Pebay C, Sella C, Thouin L. Theory and experiments of transport at channel microband electrodes under laminar flows. 2. Electrochemical regimes at double microband assemblies under steady state. Anal Chem 2009; 80:9483-90. [PMID: 19007242 DOI: 10.1021/ac801605v] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The development of any particular analytical or preparative applications using electrochemical techniques in microfluidic devices requires integration of microelectrodes. This involves detailed predictions for optimizing the design of devices and selecting the best hydrodynamic conditions. For this purpose, we undertook a series of works aimed at a precise investigation of mass transport near electrodes with focus on analytical measurements. Part I of this series (Anal. Chem. 2007, 79, 8502-8510) evaluated the common case of a single microband electrode embedded within a microchannel under laminar flow. The present work (Part 2) investigated the case of a pair of microband electrodes operating either in generator-generator or generator-collector modes. The influence of the confining effect and flow velocity on the amperometric responses was examined on the basis of numerical simulations under steady-state regime. Several situations were identified, each of them corresponding to specific interactions taking place between the electrodes. Related conditions were extracted to establish a zone diagram describing all the situations. These predictions were systematically validated by experimental measurements. The results show that amperometric detections within microchannels can be performed at dual electrodes with higher analytical performances than at single ones.
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Affiliation(s)
- Christian Amatore
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 Pasteur, 24 rue Lhomond, F-75231 Paris Cedex 05, France.
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36
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Amatore C, Klymenko OV, Oleinick AI, Svir I. Electrochemical Determination of Flow Velocity Profile in a Microfluidic Channel from Steady-State Currents: Numerical Approach and Optimization of Electrode Layout. Anal Chem 2009; 81:7667-76. [DOI: 10.1021/ac9010827] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christian Amatore
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “PASTEUR”, 24 rue Lhomond, 75231 Paris Cedex 05, France, and Mathematical and Computer Modelling Laboratory, Kharkov National University of Radioelectronics, 14 Lenin Avenue, 61166 Kharkov, Ukraine
| | - Oleksiy V. Klymenko
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “PASTEUR”, 24 rue Lhomond, 75231 Paris Cedex 05, France, and Mathematical and Computer Modelling Laboratory, Kharkov National University of Radioelectronics, 14 Lenin Avenue, 61166 Kharkov, Ukraine
| | - Alexander I. Oleinick
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “PASTEUR”, 24 rue Lhomond, 75231 Paris Cedex 05, France, and Mathematical and Computer Modelling Laboratory, Kharkov National University of Radioelectronics, 14 Lenin Avenue, 61166 Kharkov, Ukraine
| | - Irina Svir
- Département de Chimie, Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 “PASTEUR”, 24 rue Lhomond, 75231 Paris Cedex 05, France, and Mathematical and Computer Modelling Laboratory, Kharkov National University of Radioelectronics, 14 Lenin Avenue, 61166 Kharkov, Ukraine
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37
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Amatore C, Da Mota N, Sella C, Thouin L. General Concept of High-Performance Amperometric Detector for Microfluidic (Bio)Analytical Chips. Anal Chem 2008; 80:4976-85. [DOI: 10.1021/ac800227t] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christian Amatore
- UMR 8640 “PASTEUR”, Département de Chimie, Ecole Normale Supérieure, CNRS and Université Pierre et Marie Curie 24, rue Lhomond, 75231 Paris Cedex 05, France
| | - Nicolas Da Mota
- UMR 8640 “PASTEUR”, Département de Chimie, Ecole Normale Supérieure, CNRS and Université Pierre et Marie Curie 24, rue Lhomond, 75231 Paris Cedex 05, France
| | - Catherine Sella
- UMR 8640 “PASTEUR”, Département de Chimie, Ecole Normale Supérieure, CNRS and Université Pierre et Marie Curie 24, rue Lhomond, 75231 Paris Cedex 05, France
| | - Laurent Thouin
- UMR 8640 “PASTEUR”, Département de Chimie, Ecole Normale Supérieure, CNRS and Université Pierre et Marie Curie 24, rue Lhomond, 75231 Paris Cedex 05, France
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38
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Reconstruction of hydrodynamic flow profiles in a rectangular channel using electrochemical methods of analysis. Electrochim Acta 2007. [DOI: 10.1016/j.electacta.2007.03.066] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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39
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Harvey S, Parker K, O’Hare D. Theoretical evaluation of the collection efficiency at ring-disc microelectrodes. J Electroanal Chem (Lausanne) 2007. [DOI: 10.1016/j.jelechem.2007.07.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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40
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Amatore C, Da Mota N, Sella C, Thouin L. Theory and Experiments of Transport at Channel Microband Electrodes under Laminar Flows. 1. Steady-State Regimes at a Single Electrode. Anal Chem 2007; 79:8502-10. [DOI: 10.1021/ac070971y] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christian Amatore
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “ Pasteur ”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Nicolas Da Mota
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “ Pasteur ”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Catherine Sella
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “ Pasteur ”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
| | - Laurent Thouin
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 “ Pasteur ”, 24 rue Lhomond, F-75231 Paris Cedex 05, France
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41
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Amatore C, Klymenko OV, Oleinick A, Svir I. In Situ and On-Line Monitoring of Hydrodynamic Flow Profiles in Microfluidic Channels Based on Microelectrochemistry: Optimization of Channel Geometrical Parameters for Best Performance of Flow Profile Reconstruction. Chemphyschem 2007; 8:1870-4. [PMID: 17663494 DOI: 10.1002/cphc.200700297] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A theoretical approach for flow profile reconstruction in a rectangular microfluidic channel equipped with one or two microband electrodes working in generator-collector and generator-generator regimes was proposed by us previously (ChemPhysChem 2005, 6, 1581-1589; ChemPhysChem 2006, 7, 482-487). The purpose of the current study is to determine the ranges of dimensionless parameters corresponding to the highest sensitivity of the minimized functional to the shape of the flow profile. By application of a cubic spline to approximate the flow profile and analysis of the least-squares functional, which can then be represented as a function of one variable, we derive the area of optimal method performance. Thus, mathematical confirmation of our previous theoretical physical predictions could be obtained.
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Affiliation(s)
- Christian Amatore
- Ecole Normale Supérieure, Departement de Chimie, UMR CNRS 8640 PASTEUR', 24 rue Lhomond, 75231 Paris Cedex 05, France.
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42
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In-channel modification of electrochemical detector for the detection of bio-targets on microchip. Electrochem commun 2007. [DOI: 10.1016/j.elecom.2007.02.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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43
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Amatore C, Klymenko OV, Svir I. In situ and online monitoring of hydrodynamic flow profiles in microfluidic channels based upon microelectrochemistry: optimization of electrode locations. Chemphyschem 2007; 7:482-7. [PMID: 16463337 DOI: 10.1002/cphc.200500400] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Herein, we extend our previous approach concerning the reconstruction of profiles of pressure-driven hydrodynamic flow in microfluidic channels based on current measurements at band electrode(s) [see the preceding paper ChemPhysChem 2005, 6, 1581]. We address the central issue of optimization of geometrical parameters describing the electrode(s) assembly (a single band and two bands working in generator-collector mode) within the channel flow cell to enhance the speed and precision of the flow profile reconstruction method.
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Affiliation(s)
- Christian Amatore
- Ecole Normale Supérieure, Department de Chimie, UMR CNRS ENS UPMC 8640 PASTEUR', 24 rue Lhomond, 75231 Paris Cedex 05 (France).
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44
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Wain AJ, Compton RG, Le Roux R, Matthews S, Fisher AC. Microfluidic Channel Flow Cell for Simultaneous Cryoelectrochemical Electron Spin Resonance. Anal Chem 2007; 79:1865-73. [PMID: 17269792 DOI: 10.1021/ac061910n] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel microfluidic electrochemical channel flow cell has been constructed for in situ operation in a cylindrical TE011 resonant ESR cavity under variable temperature conditions. The cell has a U-tube configuration, consisting of an inlet and outlet channel which run parallel and contain evaporated gold film working, pseudo-reference, and counter electrodes. This geometry was employed to permit use in conjunction with variable temperature apparatus which does not allow a flow-through approach. The cell is characterized qualitatively and quantitatively using the one-electron reduction of p-bromonitrobenzene in acetonitrile at room temperature as a model system, and the ESR signal-flow rate response is validated by use of three-dimensional digital simulation of the concentration profile for a stable electrogenerated radical species under hydrodynamic conditions. The cell is then used to obtain ESR spectra for a number of radical species in acetonitrile at 233 K, including the radical anions of m- and p-iodonitrobenzene, o-bromonitrobenzene, and m-nitrobenzyl chloride, the latter three being unstable at room temperature. Spectra are also presented for the radical anion of 2-chloranthraquinone and the crystal violet radical, which display improved resolution at low temperatures.
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Affiliation(s)
- Andrew J Wain
- Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QZ, UK
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45
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Harvey SLR, Parker KH, O'Hare D. Developing a tissue perfusion sensor. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2007; 2007:2689-2692. [PMID: 18002549 DOI: 10.1109/iembs.2007.4352883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The development of a electrochemical tissue perfusion sensor is presented. The sensor is a platinum/platinum ring-disc microelectrode that relies on the principle of collector-generator to monitor mass transport within its vicinity. Tissue perfusion is a mass transport mechanism that describes the movement of respiratory gases, nutrients and metabolites in tissue. The sensor's capability of detecting perfusion at the cellular level in a continuous fashion is unique. This sensor will provide insight into the way nutrients and metabolites are transported in tissue especially in cases were perfusion is low such as in wounds or ischemic tissue. We present experimental work for the development and testing of the sensors in vitro. Experimental flow recordings in free steam solutions as well as the flow through tissue-like media are shown. Tests on post operative human tissue are also presented. The sensor's feature such as the continuous recoding capacities, spatial resolution and the measurement range from ml/min to microl/min are highlighted.
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Affiliation(s)
- S L R Harvey
- Department of Bioengineering, Imperial College London, London, UK
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46
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Thompson M, Compton RG. Voltammetric Monitoring of Transient Hydrodynamic Flow Profiles in Microfluidic Flow Cells. Anal Chem 2006; 79:626-31. [PMID: 17222029 DOI: 10.1021/ac0612022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We consider the transition to steady-state flow in the inlet region of a hydrodynamic channel cell and show that a microelectrode positioned within this inlet region allows chronoamperometric results to be recorded, from which information about the extent of the development of the flow profile may be deduced as well as information about the precise dimensions of the microfluidic channel.
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Affiliation(s)
- Mary Thompson
- Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, United Kingdom
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47
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Electrochemical time-of-flight responses at double-band generator-collector devices under pulsed conditions. J Electroanal Chem (Lausanne) 2006. [DOI: 10.1016/j.jelechem.2006.04.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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48
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Dittrich PS, Tachikawa K, Manz A. Micro Total Analysis Systems. Latest Advancements and Trends. Anal Chem 2006; 78:3887-908. [PMID: 16771530 DOI: 10.1021/ac0605602] [Citation(s) in RCA: 564] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Petra S Dittrich
- Institute for Analytical Sciences, Bunsen-Kirchhoff-Strasse 11, D-44139 Dortmund, Germany
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49
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Morf WE, Koudelka-Hep M, de Rooij NF. Theoretical treatment and computer simulation of microelectrode arrays. J Electroanal Chem (Lausanne) 2006. [DOI: 10.1016/j.jelechem.2006.01.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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50
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Simulation Study of Nano Aqueous Flow Sensor Based on Amperometric Measurement. SENSORS 2006. [DOI: 10.3390/s6050473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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