Sol−Gel Immobilization of Lactate Oxidase from Organic Solvent: Toward the Advanced Lactate Biosensor

Yashina, E. I.; Борисова, А. В.; Karyakina, Elena E.; Shchegolikhina, Olga I.; Vagin, Mikhail; Sakharov, D. A.; Tonevitsky, Alexander G.; Karyakin, Arkady A.

doi:10.1021/ac9027615

Cited by 74 publications

(81 citation statements)

References 23 publications

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“…In P apers I -I V , enzyme entrapment in a sol-gel matrix containing the hydrophobic mediator f rom a water-organic mix ture with a high content of organic phase 104 was used (see section 4. 1.…”

Section: 2 I Mmobilisation Methods Used In the Work S Ol-gel Procementioning

confidence: 99%

“…Higher concentrations of water lead to spontaneous hydrolysis and condensation and theref ore to a heterogeneous membrane. 104 In P apers I -I I I , we used the concept of enzyme immobilisation f rom waterorganic mix tures with a high content of organic solvent, based on the knowledge that enzymes can retain their activity af ter being ex posed to such media. 105,106 It has been shown previously that the dependence of the enzyme catalytic activity in a water-organic mix ture on the organic solvent concentration has three regions.…”

Section: Mmobilisation F Rom Organic Solventmentioning

confidence: 99%

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Facilitating electron transfer in bioelectrocatalytic systems

Sekretaryova¹

2016

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During the course of the research underlying this thesis, Alina Sekretaryova was enrolled in Forum Scientium, a multidisciplinary doctoral programme at Linköping University, Sweden Alina Sekretaryova, 2016, unless otherwise noted. Cover design by Alina Sekretaryova Linköping studies in science and technology Dissertation No. 1738 Printed in Sweden by LiU-Tryck, Linköping, Sweden, 2016 iii ABSTRACT Bioelectrocatalytic systems are based on biological entities, such as enzymes, whole cells, parts of cells or tissues, which catalyse electrochemical processes that involve the interaction between chemical change and electrical energy. In all cases, enzymes, isolated or residing inside cells or part of cells, implement biocatalysis. Electron transfer phenomena, within the protein molecules and between biological redox systems and electronics, enable the development of various bioelectrocatalytic systems, which can be used both for fundamental investigations of enzymatic biological processes by electrochemical methods and for applied purposes, such as power generation, bioremediation, chemical synthesis and biosensing.Electrical communication between the biocatalysts redox centre and an electrode is essential for the functioning of the system. This can be established using two main mechanisms: indirect electron transfer and direct electron transfer. The efficiency of the electron transfer influences important parameters such as the turnover rate of the biocatalyst, the generated current density and partially the stability of the system. These in turn determine the response time, sensitivity, detection limit and operational stability of biosensors or the power densities and current output of biofuel cells, and hence they should be carefully considered when designing bioelectrocatalytic systems.This thesis focuses on approaches that facilitate electron transfer in bioelectrocatalytic systems based on mediated and direct electron transfer mechanisms. Both fundamental aspects of electron transfer in bioelectrocatalytic systems and applications of such systems for biosensing and power generation are considered. First, a new hydrophobic mediator for oxidases, unsubstituted phenothiazine, and its improved electron transfer properties in comparison with commonly used mediators are discussed. Application of the mediator in electrochemical biosensors is demonstrated by glucose, lactate and cholesterol sensing. Utilisation of mediated biocatalytic cholesterol oxidation as the anodic reaction for the construction of a biofuel cell, acting as a power supply and an analytical device at the same time, is investigated as a "self-powered" biosensor. In addition, the enhancement of mediated bioelectrocatalysis by the employment of microelectrodes as a transducer is examined. The effect of surface roughness on the current response of the microelectrodes under conditions of convergent diffusion is considered. The applicability of the laccase-based system for total phenol analysis of weakly supported water is demonstrated. Finally, a...

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Section: 2 I Mmobilisation Methods Used In the Work S Ol-gel Procementioning

confidence: 99%

Section: Mmobilisation F Rom Organic Solventmentioning

confidence: 99%

Facilitating electron transfer in bioelectrocatalytic systems

Sekretaryova¹

2016

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“…Enzyme immobilisation was carried out from water-organic mixture with the high content of organic solvent (Yashina et al 2010). Aqueous solution of the appropriate enzyme (GOx or ChOx or LOx) was suspended in an isopropanol solution of γ-aminopropyltriethoxysiloxane containing PTZ.…”

Section: Enzyme Immobilisationmentioning

confidence: 99%

Unsubstituted phenothiazine as a superior water-insoluble mediator for oxidases

Sekretaryova

Vagin

Beni

et al. 2014

Biosensors and Bioelectronics

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The mediation of oxidases: glucose oxidase (GOx), lactate oxidase (LOx) and cholesterol oxidase (ChOx) by a new electron shuttling mediator, unsubstituted phenothiazine (PTZ), was studied. Cyclic voltammetry and rotating-disk electrode measurements in nonaqueous media were used to determine the diffusion characteristics of the mediator and the kinetics of its reaction with GOx, giving a second-order rate constant of 7.6 × 10 3 M -1 s -1 to 2.1 × 10 4 M -1 s -1 for water -acetonitrile solutions containing 5 % to 15 % water. These values are in the range reported for commonly used azine-type mediators, indicating that PTZ is able to function as an efficient mediator. PTZ and GOx, LOx and ChOx were successfully co-immobilized in sol-gel membrane on a screen-printed electrode to construct glucose, lactate and cholesterol biosensors, respectively, which were then optimised in terms of stability and sensitivity. The electrocatalytic oxidation responses showed a dependence on substrate concentration ranging from 0.6 to 32 mM for glucose, from 19 to 565 mM for lactate and from 0.015 to 1.0 mM for cholesterol detection.Oxidation of substrates on the surface of electrodes modified with PTZ and enzyme membrane was investigated with double-step chronoamperometry and the results showed that the PTZ 2 displays excellent electrochemical catalytic activities even when immobilised on the surface of the electrode. Highlights: The kinetics of the electrocatalytic oxidation of glucose with GOx mediated by a new electron shuttling mediator, PTZ, was studied. PTZ delivers superior potential performance among azine-type redox mediators for GOx. PTZ and GOx, LOx and ChOx were successfully co-immobilized in sol-gel membrane on a screen-printed electrode to construct glucose, lactate and cholesterol biosensors, respectively. Second-order rate constants for the reaction between the mediator and variety of oxidases co-immobilised inside a sol-gel membrane were obtained by chronoamperometry.

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“…[12][13][14][15] Among advantages of the PB based biosensors is their applicability for wearable devices, for example, for monitoring of undiluted sweat. 15 We note that the use of noble metals including platinum for analysis of sweat is impossible because this excreted liquid contains various peptides irreversibly inactivating these electrocatalysts.…”

mentioning

confidence: 99%

Communication—Accessing Stability of Oxidase-Based Biosensors via Stabilizing the Advanced H₂O₂Transducer

Карпова

Karyakina

Karyakin

2017

J. Electrochem. Soc.

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Operational stability of biosensors is of particular importance especially for wearable devices. Prussian Blue (PB) based advanced hydrogen peroxide transducer, 1000 times more active and selective than platinum, is deposited onto screen-printed structures and stabilized with nickel hexacyanoferrate (NiHCF), both in open circuit mode. Operational stability of PB-NiHCF bilayer based biosensors and labile lactate oxidase is significantly improved in terms of twice longer half inactivation and ≈3.5 times lower inactivation constant. The dynamic range of PB-NiHCF based biosensors is similar to it for conventional PB based ones, which allows using the former for similar purposes drastically improving their performance characteristics.

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Sol−Gel Immobilization of Lactate Oxidase from Organic Solvent: Toward the Advanced Lactate Biosensor

Cited by 74 publications

References 23 publications

Facilitating electron transfer in bioelectrocatalytic systems

Facilitating electron transfer in bioelectrocatalytic systems

Unsubstituted phenothiazine as a superior water-insoluble mediator for oxidases

Communication—Accessing Stability of Oxidase-Based Biosensors via Stabilizing the Advanced H₂O₂Transducer

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Sol−Gel Immobilization of Lactate Oxidase from Organic Solvent: Toward the Advanced Lactate Biosensor

Cited by 74 publications

References 23 publications

Facilitating electron transfer in bioelectrocatalytic systems

Facilitating electron transfer in bioelectrocatalytic systems

Unsubstituted phenothiazine as a superior water-insoluble mediator for oxidases

Communication—Accessing Stability of Oxidase-Based Biosensors via Stabilizing the Advanced H2O2Transducer

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Product

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Communication—Accessing Stability of Oxidase-Based Biosensors via Stabilizing the Advanced H₂O₂Transducer