1
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Using commercial calcium ionophores to make lanthanide sensors. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08220-5] [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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2
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Solovyeva EV, Lu H, Khripoun GA, Mikhelson KN, Kazarian SG. In situ ATR-FTIR spectroscopic imaging of PVC, plasticizer and water in solvent-polymeric ion-selective membrane containing Cd2+-selective neutral ionophore. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2020.118798] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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3
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Krata AA, Stelmach E, Wojciechowski M, Bulska E, Maksymiuk K, Michalska A. Insights into Primary Ion Exchange between Ion-Selective Membranes and Solution. From Altering Natural Isotope Ratios to Isotope Dilution Inductively Coupled Plasma Mass Spectrometry Studies. ACS Sens 2020; 5:3930-3938. [PMID: 33301318 PMCID: PMC7771020 DOI: 10.1021/acssensors.0c01585] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although ion-selective electrodes have been routinely used for decades now, there are still gaps in experimental evidence regarding how these sensors operate. This especially applies to the exchange of primary ions occurring for systems already containing analyte ions from the pretreatment step. Herein, for the first time, we present an insight into this process looking at the effect of altered ratios of naturally occurring analyte isotopes and achieving isotopic equilibrium. Benefiting from the same chemical properties of all isotopes of analyte ions and spatial resolution offered by laser ablation and inductively coupled plasma mass spectrometry, obtaining insights into primary ion diffusion in the preconditioned membrane is possible. For systems that have reached isotopic equilibrium in the membrane through ion exchange and between the membrane phase and the sample, quantification of primary ions in the membrane is possible using an isotope dilution approach for a heterogeneous system (membrane-liquid sample). Experimental results obtained for silver-selective membrane show that the primary ion diffusion coefficient in the preconditioned membrane is close to (6 ± 1) × 10-9 cm2/s, being somewhat lower compared to the previously reported values for other cations. Diffusion of ions in the membrane is the rate limiting step in achieving isotopic exchange equilibrium between the ion-selective membrane phase and sample solution. On the contrary to previous reports, quantification of silver present in the membrane clearly shows that contact of the membrane with silver nitrate solution of concentration 10-3 M leads to pronounced accumulation of silver ions in the membrane, reaching almost 150% of ion exchanger amount. The magnitude of this effect increases for higher concentration of the electrolyte in the solution.
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Affiliation(s)
- Agnieszka Anna Krata
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
- Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Emilia Stelmach
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Marcin Wojciechowski
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
- Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Ewa Bulska
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
- Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Krzysztof Maksymiuk
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Agata Michalska
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
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4
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Lindner E, Guzinski M, Pendley B, Chaum E. Plasticized PVC Membrane Modified Electrodes: Voltammetry of Highly Hydrophobic Compounds. MEMBRANES 2020; 10:E202. [PMID: 32867276 PMCID: PMC7558981 DOI: 10.3390/membranes10090202] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/17/2020] [Accepted: 08/21/2020] [Indexed: 12/30/2022]
Abstract
In the last 50 years, plasticized polyvinyl chloride (PVC) membranes have gained unique importance in chemical sensor development. Originally, these membranes separated two solutions in conventional ion-selective electrodes. Later, the same membranes were applied over a variety of supporting electrodes and used in both potentiometric and voltammetric measurements of ions and electrically charged molecules. The focus of this paper is to demonstrate the utility of the plasticized PVC membrane modified working electrode for the voltammetric measurement of highly lipophilic molecules. The plasticized PVC membrane prevents electrode fouling, extends the detection limit of the voltammetric methods to sub-micromolar concentrations, and minimizes interference by electrochemically active hydrophilic analytes.
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Affiliation(s)
- Ernő Lindner
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA;
| | - Marcin Guzinski
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (M.G.); (E.C.)
| | - Bradford Pendley
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA;
| | - Edward Chaum
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (M.G.); (E.C.)
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5
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Kondratyeva YO, Solovyeva EV, Khripoun GA, Mikhelson KN. Paradox of the Variation of the Bulk Resistance of Potassium Ion-Selective Electrode Membranes within Nernstian Potentiometric Response Range. RUSS J ELECTROCHEM+ 2019. [DOI: 10.1134/s1023193519110090] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Egorov VV, Novakovskii AD. On the possibilities of potentiometric analysis in presence of small concentrations of highly interfering foreign ions: Ways for reducing the interference. J Electroanal Chem (Lausanne) 2019. [DOI: 10.1016/j.jelechem.2019.113234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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7
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Voltammetric Determination of Diffusion Coefficients in Polymer Membranes: Guidelines to Minimize Errors. ELECTROANAL 2017. [DOI: 10.1002/elan.201700695] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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8
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Sheppard JB, Hambly B, Pendley B, Lindner E. Voltammetric determination of diffusion coefficients in polymer membranes. Analyst 2017; 142:930-937. [DOI: 10.1039/c6an02671k] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The diffusion-controlled transport of ions and molecules through polymer membranes utilized in chemical and biosensors is often the key factor determining the response characteristics of these sensors. A simple voltammetric method utilizing a planar electrochemical cell allows the rapid determination of diffusion coefficients in resistive polymer membranes.
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Affiliation(s)
| | - Bradley Hambly
- Department of Biomedical Engineering
- University of Memphis
- Memphis
- USA
| | - Bradford Pendley
- Department of Biomedical Engineering
- University of Memphis
- Memphis
- USA
| | - Erno Lindner
- Department of Biomedical Engineering
- University of Memphis
- Memphis
- USA
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9
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Ghahraman Afshar M, Crespo GA, Bakker E. Flow Chronopotentiometry with Ion-Selective Membranes for Cation, Anion, and Polyion Detection. Anal Chem 2016; 88:3945-52. [DOI: 10.1021/acs.analchem.6b00141] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Majid Ghahraman Afshar
- 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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10
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Crespo GA, Ghahraman Afshar M, Bakker E. Chronopotentiometry of pure electrolytes with anion-exchange donnan exclusion membranes. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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12
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Qin W, Liang R, Fu X, Wang Q, Yin T, Song W. Trace-Level Potentiometric Detection in the Presence of a High Electrolyte Background. Anal Chem 2012; 84:10509-13. [DOI: 10.1021/ac3024312] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wei Qin
- Key Laboratory of Coastal Zone
Environmental Processes, Yantai Institute of Coastal Zone Research
(YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key
Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
| | - Rongning Liang
- Key Laboratory of Coastal Zone
Environmental Processes, Yantai Institute of Coastal Zone Research
(YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key
Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
- Graduate University of the Chinese Academy of Sciences, Beijing 100049,
P. R. China
| | - Xiuli Fu
- Key Laboratory of Coastal Zone
Environmental Processes, Yantai Institute of Coastal Zone Research
(YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key
Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
| | - Qianwen Wang
- Key Laboratory of Coastal Zone
Environmental Processes, Yantai Institute of Coastal Zone Research
(YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key
Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
| | - Tanji Yin
- Key Laboratory of Coastal Zone
Environmental Processes, Yantai Institute of Coastal Zone Research
(YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key
Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
| | - Wenjing Song
- Key Laboratory of Coastal Zone
Environmental Processes, Yantai Institute of Coastal Zone Research
(YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key
Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
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13
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Ishimatsu R, Izadyar A, Kabagambe B, Kim Y, Kim J, Amemiya S. Electrochemical mechanism of ion-ionophore recognition at plasticized polymer membrane/water interfaces. J Am Chem Soc 2011; 133:16300-8. [PMID: 21882873 DOI: 10.1021/ja207297q] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Here, we report on the first electrochemical study that reveals the kinetics and molecular level mechanism of heterogeneous ion-ionophore recognition at plasticized polymer membrane/water interfaces. The new kinetic data provide greater understanding of this important ion-transfer (IT) process, which determines various dynamic characteristics of the current technologies that enable highly selective ion sensing and separation. The theoretical assessment of the reliable voltammetric data confirms that the dynamics of the ionophore-facilitated IT follows the one-step electrochemical (E) mechanism controlled by ion-ionophore complexation at the very interface in contrast to the thermodynamically equivalent two-step electrochemical-chemical (EC) mechanism based on the simple transfer of an aqueous ion followed by its complexation in the bulk membrane. Specifically, cyclic voltammograms of Ag(+), K(+), Ca(2+), Ba(2+), and Pb(2+) transfers facilitated by highly selective ionophores are measured and analyzed numerically using the E mechanism to obtain standard IT rate constants in the range of 10(-2) to 10(-3) cm/s at both plasticized poly(vinyl chloride) membrane/water and 1,2-dichloroethane/water interfaces. We demonstrate that these strongly facilitated IT processes are too fast to be ascribed to the EC mechanism. Moreover, the little effect of the viscosity of nonaqueous media on the IT kinetics excludes the EC mechanism, where the kinetics of simple IT is viscosity-dependent. Finally, we employ molecular level models for the E mechanism to propose three-dimensional ion-ionophore complexation at the two-dimensional interface as the unique kinetic requirement for the thermodynamically facilitated IT.
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Affiliation(s)
- Ryoichi Ishimatsu
- Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, USA
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14
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Lindfors T, Szücs J, Sundfors F, Gyurcsányi RE. Polyaniline Nanoparticle-Based Solid-Contact Silicone Rubber Ion-Selective Electrodes for Ultratrace Measurements. Anal Chem 2010; 82:9425-32. [DOI: 10.1021/ac102099p] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tom Lindfors
- Laboratory of Analytical Chemistry, Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland, Academy of Finland, Helsinki, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, Research Group of Technical Analytical Chemistry of the Hungarian Academy of Sciences, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Júlia Szücs
- Laboratory of Analytical Chemistry, Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland, Academy of Finland, Helsinki, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, Research Group of Technical Analytical Chemistry of the Hungarian Academy of Sciences, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Fredrik Sundfors
- Laboratory of Analytical Chemistry, Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland, Academy of Finland, Helsinki, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, Research Group of Technical Analytical Chemistry of the Hungarian Academy of Sciences, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Róbert E. Gyurcsányi
- Laboratory of Analytical Chemistry, Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo, Finland, Academy of Finland, Helsinki, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, Research Group of Technical Analytical Chemistry of the Hungarian Academy of Sciences, H-1111 Budapest, Szt. Gellért tér 4, Hungary
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15
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Morf WE, Pretsch E, De Rooij NF. Theoretical Treatment and Numerical Simulation of Potential and Concentration Profiles in Extremely Thin Non-Electroneutral Membranes Used for Ion-Selective Electrodes. J Electroanal Chem (Lausanne) 2010; 642:45-56. [PMID: 23255874 PMCID: PMC3523753 DOI: 10.1016/j.jelechem.2010.01.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The applicability of extremely thin non-electroneutral membranes for ion-selective electrodes (ISEs) is investigated. A theoretical treatment of potential and concentration profiles in space-charge membranes of << 1 μm thickness is presented. The theory is based on the Nernst-Planck equation for ion fluxes, which reduces to Boltzmann's formula at equilibrium, and on the Poisson relationship between space-charge density and electric field gradient. A general solution in integral form is obtained for the potential function and the corresponding ion profiles at equilibrium. A series of explicit sub-solutions is derived for particular cases. Membrane systems with up to three different ion species are discussed, including trapped ionic sites and co-extracted ions. Solid-contacted thin membranes (without formation of aqueous films at the inner interface) are shown to exhibit a sub-Nernstian response. The theoretical results are confirmed by numerical simulations using a simplified finite-difference procedure based on the Nernst-Planck-Poisson model, which are shown to be in excellent agreement.
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Affiliation(s)
- W E Morf
- Institute of Microengineering (IMT), SAMLAB, Federal Institute of Technology (EPFL STI), CH-2000 Neuchâtel, Switzerland
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16
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Zook JM, Bodor S, Gyurcsányi RE, Lindner E. Interpretation of chronopotentiometric transients of ion-selective membranes with two transition times. J Electroanal Chem (Lausanne) 2010; 638:254-261. [PMID: 20161602 DOI: 10.1016/j.jelechem.2009.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Passing currents through ion-selective membranes has contributed to the development of a variety of novel methods. In this work, chronopotentiometric (CP) transients with two transition times (breakpoints) are presented for the first time, with the theoretical interpretation of such voltage transients. The validity of our theory has been confirmed in experiments utilizing ETH 5294 chromoionophore-based pH sensitive membranes with and without lipophilic background electrolyte and ETH 5234 ionophore-based calcium selective membranes in which the ionophore forms 3:1 complexes with Ca(2+) ions. The conditions under which two breakpoints can be identified in the chronopotentiometric voltage transients are discussed.Spectroelectrochemical microscopy (SpECM) is used to show that the two breakpoints in the CP curves emerge approximately when the free ionophore and ion-ionophore complex concentrations approach zero at the opposite membrane-solution interfaces. The two breakpoint times can be utilized to follow simultaneously the concentration changes of the free ionophore, the ion-ionophore complex, and the mobile anionic sites in cation-selective membranes. In membranes with known composition, the time instances where breakpoints occur can be used to estimate the free ionophore and the ion-ionophore complex diffusion coefficients.
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Affiliation(s)
- Justin M Zook
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA
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17
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Zook JM, Bodor S, Lindner E, Tóth K, Gyurcsányi R. Assessment of Ion-Ionophore Complex Diffusion Coefficients in Solvent Polymeric Membranes. ELECTROANAL 2009. [DOI: 10.1002/elan.200904631] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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18
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Memory Effects of Ion-Selective Electrodes: Theory and Computer Simulation of the Time-Dependent Potential Response to Multiple Sample Changes. J Electroanal Chem (Lausanne) 2009; 633:137-145. [PMID: 20376292 DOI: 10.1016/j.jelechem.2009.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A straightforward theoretical description of the time-dependent response of ion-selective membrane electrodes to multiple sample changes is presented. The derivation makes use of an approximation for the ion fluxes in the membrane, and of the superposition of partial fluxes induced by the step-changes. The general theory allows for any number of samples and ions. It is applied for the analysis of memory effects that reflect the influence of preceding samples on subsequent measurements. Various phenomena are discussed, including super-, near-, or sub-nernstian responses, shifts of apparent reference potentials, and potential dips with domains of reversed slopes. The theoretical results agree well with virtual experiments based on computer simulation.
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19
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Höfler L, Bedlechowicz I, Vigassy T, Gyurcsányi RE, Bakker E, Pretsch E. Limitations of current polarization for lowering the detection limit of potentiometric polymeric membrane sensors. Anal Chem 2009; 81:3592-9. [PMID: 19338286 DOI: 10.1021/ac802588j] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Ion fluxes across polymeric ion-selective membranes are a decisive parameter dictating the lower detection limit of potentiometric ion sensors. An applied current was earlier proposed to counteract such fluxes and reduce the detection limit to ultratrace levels. So far, however, the method has not been used in practical situations since the correct current amplitude requires prior knowledge of the sample composition. This paper explores the use of the stir effect to evaluate the optimal current by theory and experiments. It is shown that the traditionally used steady-state model assuming a uniform distribution of ion exchanger in the membrane, fixed with time, violates the electroneutrality condition. A modified steady-state model is introduced that allows for a concentration tilt of the ion exchanger and predicts that a stir effect can indeed be utilized to find the optimal current. Ideally, by choosing the optimal current and very long measurement times, the thermodynamic detection limit might be obtained. However, in practice the stir effect declines at low concentrations and the conditions are far from steady state. Therefore, the improvement of the lower detection limit achievable by galvanostatic control is only about 1 order of magnitude. A numerical finite-difference approximation is shown to trace the experimental potential responses of silver-selective electrodes well and to reproduce the stir effect adequately, even for different conditioning protocols. The stir effect is successfully used to improve the detection limit of electrodes with ill-optimized inner solutions; however, significant improvements beyond what is commonly feasible by chemical optimization does not seem to be easily achievable. The results indicate that with conventional membranes the possibility of improving the detection limit by current polarization is much more limited than assumed so far.
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Affiliation(s)
- Lajos Höfler
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Hungary
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20
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Sundfors F, Lindfors T, Höfler L, Bereczki R, Gyurcsányi RE. FTIR-ATR Study of Water Uptake and Diffusion through Ion-Selective Membranes Based on Poly(acrylates) and Silicone Rubber. Anal Chem 2009; 81:5925-34. [DOI: 10.1021/ac900727w] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fredrik Sundfors
- Process Chemistry Centre, Laboratory of Analytical Chemistry, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo/Turku, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, and Research Group of Technical Analytical Chemistry, Hungarian Academy of Sciences, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Tom Lindfors
- Process Chemistry Centre, Laboratory of Analytical Chemistry, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo/Turku, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, and Research Group of Technical Analytical Chemistry, Hungarian Academy of Sciences, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Lajos Höfler
- Process Chemistry Centre, Laboratory of Analytical Chemistry, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo/Turku, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, and Research Group of Technical Analytical Chemistry, Hungarian Academy of Sciences, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Róbert Bereczki
- Process Chemistry Centre, Laboratory of Analytical Chemistry, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo/Turku, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, and Research Group of Technical Analytical Chemistry, Hungarian Academy of Sciences, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary
| | - Róbert E. Gyurcsányi
- Process Chemistry Centre, Laboratory of Analytical Chemistry, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo/Turku, Finland, Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary, and Research Group of Technical Analytical Chemistry, Hungarian Academy of Sciences, Budapest University of Technology and Economics, H-1111 Budapest, Szt. Gellért tér 4, Hungary
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21
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Zook JM, Langmaier J, Lindner E. Current-polarized ion-selective membranes: The influence of plasticizer and lipophilic background electrolyte on concentration profiles, resistance, and voltage transients. SENSORS AND ACTUATORS. B, CHEMICAL 2009; 136:410-418. [PMID: 20161192 PMCID: PMC2728498 DOI: 10.1016/j.snb.2008.12.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Lipophilic background electrolytes consisting of a lipophilic cation and a lipophilic anion, such as tetradodecylammonium tetrakis(4-chlorophenyl) borate (ETH 500), or bis(triphenylphosphoranylidene) ammonium tetrakis[3,5bis(trifluoromethyl) phenyl] borate (BTPPATFPB) are incorporated into the membranes of ion-selective electrodes (ISEs) to improve the detection limit and selectivity of the electrodes and decrease the resistance of the sensing membrane. In this work, spectroelectrochemical microscopy (SpECM) is used in conjunction with chronopotentiometry to quantify the effects of a lipophilic background electrolyte on the concentration profiles induced inside current-polarized membranes and on the measured voltage transients in chronopotentiometric experiments. In agreement with the theoretical model, the lipophilic background electrolyte incorporated into o-NPOE or DOS plasticized membranes decreases the membrane resistance and thus the contribution of migration in the overall transport across ion-selective membranes. Consequently, it has a significant influence on the changing concentration profiles of the ion-ionophore complex during chronopotentiometric experiments.
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Affiliation(s)
- Justin M. Zook
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA
| | - Jan Langmaier
- J. Heyrovsky Institute of Physical Chemistry and Electrochemistry, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Ernő Lindner
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA
- 330 Engineering Technology, The University of Memphis, Memphis, TN 38152, , ,
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