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Khanwalker M, Hatada M, LaBelle JT, Sode K. Development of an electrochemical impedance spectroscopy immunosensor for insulin monitoring employing pyrroloquinoline quinone as an ingestible redox probe. Biosens Bioelectron 2024; 250:116049. [PMID: 38290381 DOI: 10.1016/j.bios.2024.116049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 01/03/2024] [Accepted: 01/17/2024] [Indexed: 02/01/2024]
Abstract
Contemporary electrochemical impedance spectroscopy (EIS)-based biosensors face limitations in their applicability for in vivo measurements, primarily due to the necessity of using a redox probe capable of undergoing oxidation and reduction reactions in solution. Although previous investigations have demonstrated the effectiveness of EIS-based biosensors in detecting various target analytes using potassium ferricyanide as a redox probe, its unsuitability for blood or serum measurements, attributed to its inherent toxicity, poses a significant challenge. In response to this challenge, our study adopted a unique approach, focusing on the use of ingestible materials, by exploring naturally occurring substances within the body, with a specific emphasis on pyrroloquinoline quinone (PQQ). Following an assessment of PQQ's electrochemical attributes, we conducted a comprehensive series of EIS measurements. This involved the thorough characterization of the sensor's evolution, starting from the bare electrode and progressing to the immobilization of antibodies. The sensor's performance was then evaluated through the quantification of insulin concentrations ranging from 1 pM to 100 nM. A single frequency was identified for insulin measurements, offering a pathway for potential in vivo applications by combining PQQ as a redox probe with EIS measurements. This innovative approach holds promise for advancing the field of in vivo biosensing based on the EIS method.
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Affiliation(s)
- Mukund Khanwalker
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC27599, USA
| | - Mika Hatada
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC27599, USA
| | - Jeffery T LaBelle
- Department of Bioengineering, College of Engineering Science and Technology, Grand Canyon University, Phoenix, AZ, AZ85017, USA
| | - Koji Sode
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC27599, USA.
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2
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Quintero-Jaime AF, Conzuelo F, Schuhmann W, Cazorla-Amorós D, Morallón E. Multi‐wall carbon nanotubes electrochemically modified with phosphorus and nitrogen functionalities as a basis for bioelectrodes with improved performance. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.138530] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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3
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Devasurendra AM, Zhu T, Kirchhoff JR. Detection of Thiols by o
-Quinone Nanocomposite Modified Electrodes. ELECTROANAL 2016. [DOI: 10.1002/elan.201600334] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Amila M. Devasurendra
- Department of Chemistry and Biochemistry; College of Natural Sciences and Mathematics and School of Green Chemistry and Engineering; The University of Toledo; 2801 West Bancroft Street 43606 Toledo OH
| | - Tianxia Zhu
- Department of Chemistry and Biochemistry; College of Natural Sciences and Mathematics and School of Green Chemistry and Engineering; The University of Toledo; 2801 West Bancroft Street 43606 Toledo OH
| | - Jon R. Kirchhoff
- Department of Chemistry and Biochemistry; College of Natural Sciences and Mathematics and School of Green Chemistry and Engineering; The University of Toledo; 2801 West Bancroft Street 43606 Toledo OH
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Flexer V, Mano N. Wired Pyrroloquinoline Quinone Soluble Glucose Dehydrogenase Enzyme Electrodes Operating at Unprecedented Low Redox Potential. Anal Chem 2014; 86:2465-73. [DOI: 10.1021/ac403334w] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Victoria Flexer
- Centre de Recherche
Paul Pascal, UPR 8641, CNRS, F-33600 Pessac, France
- Université de Bordeaux, CRPP, UPR 8641, F-33600 Pessac, France
| | - Nicolas Mano
- Centre de Recherche
Paul Pascal, UPR 8641, CNRS, F-33600 Pessac, France
- Université de Bordeaux, CRPP, UPR 8641, F-33600 Pessac, France
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Young JA, Jiang X, Kirchhoff JR. Amperometric Detection of Histamine with a Pyrroloquinoline-Quinone Modified Electrode. ELECTROANAL 2013. [DOI: 10.1002/elan.201300114] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Flexer V, Durand F, Tsujimura S, Mano N. Efficient direct electron transfer of PQQ-glucose dehydrogenase on carbon cryogel electrodes at neutral pH. Anal Chem 2011; 83:5721-7. [PMID: 21662989 DOI: 10.1021/ac200981r] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a comprehensive study of the direct electron transfer reaction of soluble PQQ-GDH from Acinetobacter calcoaceticus. Wild-type PQQ-sGDH nonspecifically adsorbed on carbon cryogel electrodes retained its enzymatic activity for glucose and maltose oxidation at pH 7.2 and 37 °C. The cyclic voltammograms in the absence of enzymatic substrate showed 2 redox peaks that suggest a two-step, one-electron oxidation/reduction of PQQ. Calibration curves showed a linear amperometric response for a wide glucose concentration range, including the values normally found in blood. At saturation, the catalytic current reached 0.93 mA cm(-2). Altogether the experimental results suggest that the amperometric output of the electrodes and the shape of the calibration curves represent a combination of the intrinsic enzyme kinetics, the maximum rate of heterogeneous electron transfer and the substrate accessibility to the enzyme's active center caused by the confinement of the enzyme into the mesoporous structure. A new mutant enzyme, N428C, developed in our group that shows almost twice the maximum catalytic activity in homogeneous experiments in solution, also showed a DET signal on carbon cryogel electrodes for glucose electro-oxidation. The higher activity for the mutant enzyme was also verified on the electrode surface.
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Affiliation(s)
- Victoria Flexer
- Université de Bordeaux, Centre de Recherche Paul Pascal, CRPP-UPR 8641-CNRS, Pessac, France
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Kanninen P, Ruiz V, Kallio T, Anoshkin I, Kauppinen EI, Kontturi K. Simple immobilization of pyrroloquinoline quinone on few-walled carbon nanotubes. Electrochem commun 2010. [DOI: 10.1016/j.elecom.2010.06.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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8
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Jao HJ, Tsai PY, Wang CM. Unexplored interactions between pyrroloquinoline quinone and β-nicotinamide adenine dinucleotide. J Electroanal Chem (Lausanne) 2007. [DOI: 10.1016/j.jelechem.2007.05.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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9
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Shulga OV, Palmer C. Detection of V-type nerve agent degradation products at electrodes modified by PPy/PQQ using CaCl2 as supporting electrolyte. Anal Bioanal Chem 2006; 385:1116-23. [PMID: 16770578 DOI: 10.1007/s00216-006-0531-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2006] [Revised: 04/25/2006] [Accepted: 05/05/2006] [Indexed: 11/28/2022]
Abstract
Electrochemical detection without derivatization was used to detect thiol-containing degradation products of V-type nerve agents. Electropolymerization of pyrrole was used for entrapment of the biocatalyst PQQ to produce a sensor. Various parameters which affect the detection processes such as the type of the supporting electrolyte used during electrodeposition and the thickness of the polypyrrole film were examined and optimized. Electocatalytic oxidation of thiols by the PPy/PQQ electrode was strongly affected by the presence of Ca2+ cations during electrodeposition of the PPy/PQQ. Cyclic voltammetry, linear sweep voltammetry and amperometry have been used for electrode characterization. Amperometric detection of the V-type nerve agent thiol degradation products 2-(dimethylamino)ethanethiol (DMAET) and 2-(diethylamino)ethanethiol (DEAET) was performed at 0.38 V. Linear calibration plots were observed for these compounds. The detection limits of 4.5 and 3 microM were obtained for DMAET and DEAET respectively, with sensitivities of 1.18 and 1.37 nA microM(-1) cm(-2).
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Affiliation(s)
- Olga V Shulga
- Department of Chemistry, University of Montana, Missoula, MT 59812, USA.
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E Ferapontova E, Gorton L. Direct electrochemistry of heme multicofactor-containing enzymes on alkanethiol-modified gold electrodes. Bioelectrochemistry 2005; 66:55-63. [PMID: 15833703 DOI: 10.1016/j.bioelechem.2004.04.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2004] [Revised: 03/31/2004] [Accepted: 04/13/2004] [Indexed: 11/28/2022]
Abstract
Direct electrochemistry of heme multicofactor-containing enzymes, e.g., microbial theophylline oxidase (ThOx) and D-fructose dehydrogenase (FDH) from Gluconobacter industrius was studied on alkanethiol-modified gold electrodes and was compared with that of some previously studied complex heme enzymes, specifically, cellobiose dehydrogenase (CDH) and sulphite oxidase (SOx). The formal redox potentials for enzymes in direct electronic communication varied for ThOx from -112 to -101 mV (vs. Ag|AgCl), at pH 7.0, and for FDH from -158 to -89 mV, at pH 5.0 and pH 4.0, respectively, on differently charged alkanethiol layers. Direct and mediated by cytochrome c electrochemistry of FDH correlated with the existence of two active centres in the protein structure, i.e., the heme and the pyrroloquinoline quinone (PQQ) prosthetic groups. The effect of the alkanethiols of different polarity and charge on the surface properties of the gold electrodes necessary for adsorption and orientation of ThOx, FDH, CDH and SOx, favourable for the efficient electrode-enzyme electron transfer reaction, is discussed.
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Affiliation(s)
- Elena E Ferapontova
- Group of Bioinformatics, Weblab, IT Centre, Voskhod 26a, Novosibirsk 630102, Russia.
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Joshi K, Pandey P, Chen W, Mulchandani A. Ormosil Encapsulated Pyrroloquinoline Quinone-Modified Electrochemical Sensor for Thiols. ELECTROANAL 2004. [DOI: 10.1002/elan.200303040] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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Yamashita M, Pessôa CA, Kubota LT. Electrochemical behavior of pyrroloquinoline quinone immobilized on silica gel modified with zirconium oxide. J Colloid Interface Sci 2003; 263:99-105. [PMID: 12804890 DOI: 10.1016/s0021-9797(03)00327-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Pyrroloquinoline quinone (PQQ) was immobilized on the silica gel surface modified with zirconium oxide, designated as Si:Zr, by the carboxylic groups of the PQQ molecule and the zirconium oxide on the silica surface. The electrochemistry of PQQ immobilized on the Si:Zr matrix, incorporated in a carbon paste electrode, was evaluated using the cyclic voltammetry technique. The Si:Zr:PQQ-modified electrode showed a redox couple at E(m)=(E(pa1)+E(pc))/2=-0.150 V vs SCE at pH 7, close to that observed in aqueous solution, and another oxidation peak, E(pa2)=-0.100 V vs SCE. Studies in different pH solutions in the range of 3-7 showed that the first oxidation peak, E(pa1), is highly dependent on the solution pH shifting from to -0.175 to 0.100 V vs SCE, while E(pa2) remains practically constant at 0.100 V as the pH decreases from 7 to 3. The immobilized PQQ electrode presented the property to electrocatalyze the NADH at 150 mV vs SCE. The effect of addition of Ca(2+) ions on the electrode electroactivity for the NADH oxidation was also verified. Different from that observed for the PQQ immobilized on other electrode materials, the Ca(2+) ions did not influence the electrocatalytical response; however, the electrode stability was considerably improved in the presence of Ca(2+) ions, indicating that the matrix surface has a great influence on the electrochemical behavior of PQQ.
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Affiliation(s)
- Miyuki Yamashita
- Instituto de Química, UNICAMP, Universidade Estadual de Campinas, P.O. Box 6154, 13083-970, Campinas, SP, Brazil
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Inoue T, Kirchhoff JR. Determination of thiols by capillary electrophoresis with amperometric detection at a coenzyme pyrroloquinoline quinone modified electrode. Anal Chem 2002; 74:1349-54. [PMID: 11922303 DOI: 10.1021/ac0108515] [Citation(s) in RCA: 202] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A chemically modified electrode has been developed as a detector for the sensitive and selective determination of thiol-containing compounds following capillary electrophoresis separation. Electrodes were constructed by entrapment of the coenzyme pyrroloquinoline quinone (PQQ) into a polypyrrole (PPy) matrix on a 245-microm graphite electrode during electropolymerization of pyrrole in the presence of PQQ. PQQ serves as an efficient biocatalyst to mediate the oxidation of thiols at a substantially reduced overpotential relative to an unmodified electrode. Furthermore, this design takes advantage of the pH-dependent reversible electrochemical properties of PQQ, which facilitates optimization of separation and detection conditions. The PQQ/PPy-modified electrode was incorporated as an end-column detector, and a separation of homocysteine, cysteine, N-acetylcysteine, and glutathione was developed. Detection limits for these four thiols were determined to be 11, 23, 104, and 134 nM, respectively, with mass detection limits ranging from 0.29 to 3.48 fmol. The PQQ/PPy electrode was also found to be very reproducible in run-to-run, day-to-day, and electrode-to-electrode comparisons. The utility of this electrode was demonstrated for the detection of cysteine in dietary supplements and human urine, resulting in excellent agreement with reported values.
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Affiliation(s)
- Takayo Inoue
- Department of Chemistry, University of Toledo, Ohio 43606, USA
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Inoue T, Kirchhoff JR. Electrochemical detection of thiols with a coenzyme pyrroloquinoline quinone modified electrode. Anal Chem 2000; 72:5755-60. [PMID: 11128932 DOI: 10.1021/ac000716c] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A modified electrode sensor for the detection of thiols is described. The sensor was constructed by incorporation of the coenzyme pyrroloquinoline quinone (PQQ) into a polypyrrole (PPy) film on a glassy carbon electrode substrate by the electropolymerization of pyrrole in the presence of PQQ. The electrochemical properties of entrapped PQQ in the PPy film were influenced by the applied potential during electropolymerization and by film thickness, both of which were optimized to yield a stable and reproducible response for entrapped PQQ. The PQQ/ PPy sensor was utilized for the amperometric detection of cysteine, homocysteine, penicillamine, N-acetylcysteine, and glutathione. The response for each thiol in pH 8.42 borate buffer was found to be linear with detection limits (S/N = 3) ranging from 13.2 microM for glutathione to 63.7 nM for cysteine with sensitivities of 0.023 nA/microM and 4.71 nA/microM, respectively. The response and detection limits were found to be sensitive to the nature of the thiol and the solution pH. Furthermore, in the presence of dopamine, ascorbic acid, or uric acid, the pH-dependent redox potential of the PQQ catalyst allows tuning of the detection potential to enhance the selectivity for thiols over these potential electroactive interferences.
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Affiliation(s)
- T Inoue
- Department of Chemistry, University of Toledo, Ohio 43606, USA
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Curulli A, Carelli I, Trischitta O, Palleschi G. Assembling and evaluation of new dehydrogenase enzyme electrode probes obtained by electropolymerization of aminobenzine isomers and PQQ on gold, platinum and carbon electrodes. Biosens Bioelectron 1998; 12:1043-55. [PMID: 9451793 DOI: 10.1016/s0956-5663(97)00060-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Pt, Au and graphite electrodes have been coated by electropolymerization of 1,2-, 1,3-, 1,4-diaminobenzene (DAB) and 4-aminobiphenyl in the presence of PQQ using cyclic voltammetry. The activity of the modified electrodes for the oxidation of paracetamol, ascorbic and uric acid was reduced by approximately 90% as compared to the bare electrodes. Polymerization in the presence 4,5-dihydro-4,5-dioxo-1H-pyrrolo(2,3-f)quinoline-2,7,9-tricarboxilic+ ++ acid, pyrroloquinolinequinone (PQQ) led, after optimization, to electrodes capable of catalysing the electrooxidation of beta-nicotinamide adenine dinucleotide, reduced form (NADH), in the range 10(-4)-10(-2) mol/l with a detection limit of 5 x 10(-5) mol/l. Amperometric measurements of NADH have been carried out at +0.2 V and the efficiency of different electrodes based on different materials has been studied. By co-entrapment of dehydrogenase highly selective enzymes, electrodes for glucose, L-lactate and L-glutamate were obtained. Dehydrogenase substrates such as glucose, lactate and glutamate were measured in the range 5 x 10(-5)-1 x 10(-2) mol/l, with detection limits of 10(-5) and 5 x 10(-6) mol/l, respectively. Probe stability under non-dynamic conditions was evaluated over 2 months. All the probes showed a decrease of 10% over 1 month and a residual activity of 50% over 2 months.
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Affiliation(s)
- A Curulli
- Centro C.N.R. di Studio per l'Elettrochimica e la Chimica Fisica delle Interfasi, Rome, Italy
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Cosnier S. Electropolymerization of amphiphilic monomers for designing amperometric biosensors. ELECTROANAL 1997. [DOI: 10.1002/elan.1140091206] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Loughran MG, Hall JM, Turner APF. Development of a pyrroloquinoline quinone (PQQ) mediated glucose oxidase enzyme electrode for detection of glucose in fruit juice. ELECTROANAL 1996. [DOI: 10.1002/elan.1140081004] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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pH-switched electrochemistry of pyrroloquinoline quinone at Au electrodes modified by functionalized monolayers. J Electroanal Chem (Lausanne) 1996. [DOI: 10.1016/0022-0728(96)04525-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Zhao S, Luong JHT. Control of selectivity and electroactivity on underoxidized polypyrrole film electrodes. ELECTROANAL 1995. [DOI: 10.1002/elan.1140070706] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Pantano P, Kuhr WG. Enzyme-modified microelectrodes for in vivo neurochemical measurements. ELECTROANAL 1995. [DOI: 10.1002/elan.1140070502] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Electrochemical study of pyrroloquinoline quinone covalently immobilized as a monolayer onto a cystamine-modified gold electrode. J Electroanal Chem (Lausanne) 1994. [DOI: 10.1016/0022-0728(93)03010-m] [Citation(s) in RCA: 150] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Khan GF, Kobatake E, Ikariyama Y, Aizawa M. Amperometric biosensor with PQQ enzyme immobilized in a mediator-containing polypyrrole matrix. Anal Chim Acta 1993. [DOI: 10.1016/0003-2670(93)85011-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Begum A, Kobatake E, Suzawa T, Ikariyama Y, Aizawa M. New electrocatalytic biomolecular interface for fabricating a fructose dehydrogenase-based sensing system. Anal Chim Acta 1993. [DOI: 10.1016/0003-2670(93)80237-f] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Nakamura N, Kohzuma T, Suzuki S. Electrochemical Properties of Coenzyme Pyrroloquinolinequinone Using a Di-(4-pyridyl) Disulfide Modified Gold Electrode under Acidic Conditions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1993. [DOI: 10.1246/bcsj.66.1289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Modulation of the function of an enzyme immobilized in a conductive polymer by electrochemical changing of the substrate concentration. J Electroanal Chem (Lausanne) 1993. [DOI: 10.1016/0022-0728(93)80096-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Polypyrrole film electrodes electrochemically doped with tetrathiomolybdate anions: preparation and characterization. J Electroanal Chem (Lausanne) 1992. [DOI: 10.1016/0022-0728(92)80559-m] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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