51
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Yamada K, Shibata H, Suzuki K, Citterio D. Toward practical application of paper-based microfluidics for medical diagnostics: state-of-the-art and challenges. LAB ON A CHIP 2017; 17:1206-1249. [PMID: 28251200 DOI: 10.1039/c6lc01577h] [Citation(s) in RCA: 265] [Impact Index Per Article: 37.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Microfluidic paper-based analytical devices (μPADs) have emerged as a promising diagnostic platform a decade ago. In contrast to highly active academic developments, their entry into real-life applications is still very limited. This discrepancy is attributed to the gap between research developments and their practical utility, particularly in the aspects of operational simplicity, long-term stability of devices, and associated equipment. On the basis of these backgrounds, this review attempts to: 1) identify the reasons for success of paper-based devices already in the market, 2) describe the current status and remaining issues of μPADs in terms of operational complexity, signal interpretation approaches, and storage stability, and 3) discuss the possibility of mass production based on established manufacturing technologies. Finally, the state-of-the-art in commercialisation of μPADs is discussed, and the "upgrades" required from a laboratory-based prototype to an end user device are demonstrated on a specific example.
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Affiliation(s)
- Kentaro Yamada
- Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
| | - Hiroyuki Shibata
- Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
| | - Koji Suzuki
- Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
| | - Daniel Citterio
- Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
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52
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Guinovart T, Hernández-Alonso D, Adriaenssens L, Blondeau P, Rius FX, Ballester P, Andrade FJ. Characterization of a new ionophore-based ion-selective electrode for the potentiometric determination of creatinine in urine. Biosens Bioelectron 2017; 87:587-592. [DOI: 10.1016/j.bios.2016.08.025] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 07/29/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022]
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53
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Yang J, Kwak TJ, Zhang X, McClain R, Chang WJ, Gunasekaran S. Digital pH Test Strips for In-Field pH Monitoring Using Iridium Oxide-Reduced Graphene Oxide Hybrid Thin Films. ACS Sens 2016. [DOI: 10.1021/acssensors.6b00385] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jiang Yang
- Department
of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
- Environment,
Energy and Natural Resources Center, Department of Environmental Science
and Engineering, Fudan University, No. 220, Handan Road, Shanghai, 200433, China
| | - Tae Joon Kwak
- Department
of Mechanical Engineering, University of Wisconsin-Milwaukee, 3200 North Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Xiaodong Zhang
- Department
of Physics, School of Science, Tianjin University, 92 Weijin Road, Tianjin, 300354, China
| | - Robert McClain
- Department
of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Woo-Jin Chang
- Department
of Mechanical Engineering, University of Wisconsin-Milwaukee, 3200 North Cramer Street, Milwaukee, Wisconsin 53211, United States
- School of
Freshwater Sciences, University of Wisconsin-Milwaukee, 600 East Greenfield, Milwaukee, Wisconsin 53204, United States
| | - Sundaram Gunasekaran
- Department
of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
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54
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Ding J, Li B, Chen L, Qin W. A Three-Dimensional Origami Paper-Based Device for Potentiometric Biosensing. Angew Chem Int Ed Engl 2016; 55:13033-13037. [DOI: 10.1002/anie.201606268] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Indexed: 01/11/2023]
Affiliation(s)
- Jiawang Ding
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
| | - Bowei Li
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
| | - Lingxin Chen
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
| | - Wei Qin
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
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55
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Ding J, Li B, Chen L, Qin W. A Three-Dimensional Origami Paper-Based Device for Potentiometric Biosensing. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606268] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jiawang Ding
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
| | - Bowei Li
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
| | - Lingxin Chen
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
| | - Wei Qin
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation; Yantai Institute of Coastal Zone Research (YIC); Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes; YICCAS; Yantai Shandong 264003 P.R. China
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56
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Montiel L, Delgado JA, Novell M, Andrade FJ, Claver C, Blondeau P, Godard C. A Simple and Versatile Approach for the Fabrication of Paper-Based Nanocatalysts: Low Cost, Easy Handling, and Catalyst Recovery. ChemCatChem 2016. [DOI: 10.1002/cctc.201600666] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Laura Montiel
- Departament de Química Física i Inorgànica; Universitat Rovira i Virgili; C/Marceli Domingo 1 43007 Tarragona Spain
| | - Jorge A. Delgado
- Centre Tecnologic de la Química; C/Marceli Domingo 43007 Tarragona Spain
| | - Marta Novell
- Departament de Química Analítica i Química Orgànica; Universitat Rovira i Virgili; C/Marceli Domingo 1 43007 Tarragona Spain
| | - Francisco J. Andrade
- Departament de Química Analítica i Química Orgànica; Universitat Rovira i Virgili; C/Marceli Domingo 1 43007 Tarragona Spain
| | - Carmen Claver
- Departament de Química Física i Inorgànica; Universitat Rovira i Virgili; C/Marceli Domingo 1 43007 Tarragona Spain
- Centre Tecnologic de la Química; C/Marceli Domingo 43007 Tarragona Spain
| | - Pascal Blondeau
- Departament de Química Analítica i Química Orgànica; Universitat Rovira i Virgili; C/Marceli Domingo 1 43007 Tarragona Spain
| | - Cyril Godard
- Departament de Química Física i Inorgànica; Universitat Rovira i Virgili; C/Marceli Domingo 1 43007 Tarragona Spain
- Centre Tecnologic de la Química; C/Marceli Domingo 43007 Tarragona Spain
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57
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Parrilla M, Cánovas R, Andrade FJ. Enhanced Potentiometric Detection of Hydrogen Peroxide Using a Platinum Electrode Coated with Nafion. ELECTROANAL 2016. [DOI: 10.1002/elan.201600403] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Marc Parrilla
- Department of Analytical and Organic Chemistry; Universitat Rovira i Virgili; 43007 Tarragona Spain
| | - Rocío Cánovas
- Department of Analytical and Organic Chemistry; Universitat Rovira i Virgili; 43007 Tarragona Spain
| | - Francisco J. Andrade
- Department of Analytical and Organic Chemistry; Universitat Rovira i Virgili; 43007 Tarragona Spain
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58
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Vanamo U, Hupa E, Yrjänä V, Bobacka J. New Signal Readout Principle for Solid-Contact Ion-Selective Electrodes. Anal Chem 2016; 88:4369-74. [DOI: 10.1021/acs.analchem.5b04800] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ulriika Vanamo
- Laboratory
of Analytical Chemistry, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland
- Laboratory
of Materials Chemistry and Chemical Analysis, University of Turku, Vatselankatu 2, 20500 Turku, Finland
| | - Elisa Hupa
- Laboratory
of Analytical Chemistry, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland
- Graduate
School in Chemical Engineering (GSCE), Åbo Akademi University, Tavastgatan
13, FI-20500 Åbo, Finland
| | - Ville Yrjänä
- Laboratory
of Analytical Chemistry, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland
| | - Johan Bobacka
- Laboratory
of Analytical Chemistry, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland
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59
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Nery EW, Kubota LT. Integrated, paper-based potentiometric electronic tongue for the analysis of beer and wine. Anal Chim Acta 2016; 918:60-8. [PMID: 27046211 DOI: 10.1016/j.aca.2016.03.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 02/04/2016] [Accepted: 03/03/2016] [Indexed: 12/20/2022]
Abstract
The following manuscript details the stages of construction of a novel paper-based electronic tongue with an integrated Ag/AgCl reference, which can operate using a minimal amount of sample (40 μL). First, we optimized the fabrication procedure of silver electrodes, testing a set of different methodologies (electroless plating, use of silver nanoparticles and commercial silver paints). Later a novel, integrated electronic tongue system was assembled with the use of readily available materials such as paper, wax, lamination sheets, bleach etc. New system was thoroughly characterized and the ion-selective potentiometric sensors presented performance close to theoretical. An electronic tongue, composed of electrodes sensitive to sodium, calcium, ammonia and a cross-sensitive, anion-selective electrode was used to analyze 34 beer samples (12 types, 19 brands). This system was able to discriminate beers from different brands, and types, indicate presence of stabilizers and antioxidants, dyes or even unmalted cereals and carbohydrates added to the fermentation wort. Samples could be classified by type of fermentation (low, high) and system was able to predict pH and in part also alcohol content of tested beers. In the next step sample volume was minimalized by the use of paper sample pads and measurement in flow conditions. In order to test the impact of this advancement a four electrode system, with cross-sensitive (anion-selective, cation-selective, Ca(2+)/Mg(2+), K(+)/Na(+)) electrodes was applied for the analysis of 11 types of wine (4 types of grapes, red/white, 3 countries). Proposed matrix was able to group wines produced from different varieties of grapes (Chardonnay, Americanas, Malbec, Merlot) using only 40 μL of sample. Apart from that, storage stability studies were performed using a multimeter, therefore showing that not only fabrication but also detection can be accomplished by means of off-the-shelf components. This manuscript not only describes new paper-based, potentiometric sensors but also according to our knowledge is the first description of an electrochemical paper-based electronic tongue with integrated reference.
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Affiliation(s)
- Emilia Witkowska Nery
- Department of Analytical Chemistry, Institute of Chemistry - UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP, Brazil; National Institute of Science and Technology in Bioanalytics, Institute of Chemistry - UNICAMP, P.O. Box 6154, Campinas, Brazil.
| | - Lauro T Kubota
- Department of Analytical Chemistry, Institute of Chemistry - UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP, Brazil; National Institute of Science and Technology in Bioanalytics, Institute of Chemistry - UNICAMP, P.O. Box 6154, Campinas, Brazil
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60
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Hu J, Stein A, Bühlmann P. Rational design of all-solid-state ion-selective electrodes and reference electrodes. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2015.11.004] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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61
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Cuartero M, Crespo GA, Bakker E. Ionophore-Based Voltammetric Ion Activity Sensing with Thin Layer Membranes. Anal Chem 2016; 88:1654-60. [DOI: 10.1021/acs.analchem.5b03611] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Maria Cuartero
- Department of Inorganic and
Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva, Switzerland
| | - Gaston A. Crespo
- Department of Inorganic and
Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva, Switzerland
| | - Eric Bakker
- Department of Inorganic and
Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva, Switzerland
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62
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Constantinou L, Triantis IF, Hickey M, Kyriacou PA. On the merits of tetrapolar impedance spectroscopy for monitoring lithium concentration variations in human blood plasma. IEEE Trans Biomed Eng 2016; 64:601-609. [PMID: 27214887 DOI: 10.1109/tbme.2016.2570125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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63
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Wang X, Qin Y, Meyerhoff ME. Paper-based plasticizer-free sodium ion-selective sensor with camera phone as a detector. Chem Commun (Camb) 2015; 51:15176-9. [PMID: 26325367 PMCID: PMC4591243 DOI: 10.1039/c5cc06770g] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
An ionophore-based ion-selective optode platform on paper is described for the first time with a sodium optode as the example. Cellulose paper is shown to be an excellent substrate for adsorption of the required chromoionophore, ionophore, and ion-exchanger species. These adsorbed components form a hydrophobic phase that enables heterogeneous optical ion sensing in the absence of any plasticizer or organic polymer phase.
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Affiliation(s)
- Xuewei Wang
- Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor, MI 48109-1055, USA.
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64
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65
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Sun M, Johnson MA. Measurement of Total Antioxidant Capacity in Sub-μL Blood Samples Using Craft Paper-based Analytical Devices. RSC Adv 2015; 5:55633-55639. [PMID: 27642513 PMCID: PMC5026239 DOI: 10.1039/c5ra06479a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Antioxidants play a role in counteracting free radicals and reactive oxygen species and are thought to help prevent or slow the progression of many chronic diseases, such as cancer, diabetes mellitus, cardiovascular disease, and neurodegenerative diseases. Herein we report a simple way to make a colorimetric assay for measuring total antioxidant capacity (TAC) on craft paper-based analytical devices (cPADs) suitable for sub-μL volume blood samples. We incorporated a microfluidic separation mechanism for isolation of plasma from interfering blood cells. The whole diagnostic process, including cPAD construction, plasma sample preparation, assay, and image thresholding analysis, can be completed in fifteen minutes. We applied our approach toward the measurement of TAC in mice that model Huntington's disease (HD), a fatal, neurodegenerative movement disorder. Results revealed that TAC was significantly elevated in R6/2 HD model mice compared to their age-matched wild-type (WT) controls. We expect that this method, carrying a simple, fast, and sensitive assay on low-cost and disposable paper, will meet the potential needs for point-of-care (POC) testing of TAC, as well as other disease biomarkers in blood and other types of bodily fluids where limited volumes of samples are obtainable.
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Affiliation(s)
- Meng Sun
- Department of Chemistry and R. N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Michael A. Johnson
- Department of Chemistry and R. N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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66
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Hu J, Ho KT, Zou XU, Smyrl WH, Stein A, Bühlmann P. All-Solid-State Reference Electrodes Based on Colloid-Imprinted Mesoporous Carbon and Their Application in Disposable Paper-based Potentiometric Sensing Devices. Anal Chem 2015; 87:2981-7. [DOI: 10.1021/ac504556s] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Jinbo Hu
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Kieu T. Ho
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Xu U. Zou
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - William H. Smyrl
- Department
of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, United States
| | - Andreas Stein
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Philippe Bühlmann
- Department
of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
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67
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Cuartero M, Crespo GA, Bakker E. Paper-Based Thin-Layer Coulometric Sensor for Halide Determination. Anal Chem 2015; 87:1981-90. [DOI: 10.1021/ac504400w] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Maria Cuartero
- Department
of Inorganic and
Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva, Switzerland
| | - Gastón A. Crespo
- Department
of Inorganic and
Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva, Switzerland
| | - Eric Bakker
- Department
of Inorganic and
Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva, Switzerland
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68
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Sabek J, Adriaenssens L, Guinovart T, Parra EJ, Rius FX, Ballester P, Blondeau P. Chloride-Selective Electrodes Based on “Two-Wall” Aryl-Extended Calix[4]Pyrroles: Combining Hydrogen Bonds and Anion-π Interactions to Achieve Optimum Performance. Chemistry 2014; 21:448-54. [DOI: 10.1002/chem.201403853] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Indexed: 11/10/2022]
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69
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Lan WJ, Zou XU, Hamedi MM, Hu J, Parolo C, Maxwell EJ, Bühlmann P, Whitesides GM. Paper-based potentiometric ion sensing. Anal Chem 2014; 86:9548-53. [PMID: 25197763 DOI: 10.1021/ac5018088] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This paper describes the design and fabrication of ion-sensing electrochemical paper-based analytical devices (EPADs) in which a miniaturized paper reference electrode is integrated with a small ion-selective paper electrode (ISPE) for potentiometric measurements. Ion-sensing EPADs use printed wax barriers to define electrochemical sample and reference zones. Single-layer EPADs for sensing of chloride ions include wax-defined sample and reference zones that each incorporate a Ag/AgCl electrode. In EPADs developed for other electrolytes (potassium, sodium, and calcium ions), a PVC-based ion-selective membrane is added to separate the sample zone from a paper indicator electrode. After the addition of a small volume (less than 10 μL) of sample and reference solutions to different zones, ion-sensing EPADs exhibit a linear response, over 3 orders of magnitude, in ranges of electrolyte concentrations that are relevant to a variety of applications, with a slope close to the theoretical value (59.2/z mV). Ion-selective EPADs provide a portable, inexpensive, and disposable way of measuring concentrations of electrolyte ions in aqueous solutions.
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Affiliation(s)
- Wen-Jie Lan
- Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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