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Sergei V. Dzyadevych - One of the best experts on this subject based on the ideXlab platform.
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Application of ammonium-selective zeolite for enhancement of conductometric bi-enzyme Biosensor for L-arginine detection
Sensorna elektronìka ì mìkrosistemnì tehnologìï = Sensor Electronics and Microsystem Technologies, 2014Co-Authors: O Y Saiapina, Oleksandr O. Soldatkin, V M Pyeshkova, V G Melnik, Alai Walcarius, Nicole Jaffrezic-renault, N. J. Matsishin, Sergei V. DzyadevychAbstract:L-arginine conductometric Biosensors were developed on the basis of arginase and ure¬ase cross-linked by glutaraldehyde in a single bioselective membrane and modified with clinoptilo¬lite. The clinoptilolite intrinsic properties helpful for conductometric detection of L-arginine were investigated using three approaches to the creation of zeolite-containing enzymatic membranes. The developed Biosensors were compared with the L-arginine Biosensor, not modified with clinoptilolite, for the sensitivity, linear and dynamic range, detection limit, response time, operational and storage stability in L-arginine analysis. It was shown that the incorporation of ammonium-selective zeolite to the bioselective membrane of L-arginine Biosensor allows increasing the Biosensor sensitivity when applying all proposed approaches to the formation of zeolite-containing biomembranes. In addition, excellent values of both detection limit and linear range (1.0×10-5 M and 0.01–6 mM, respectively) were achieved for the Biosensor based on arginase, urease and zeolite distributed in a single bioselec-tive layer. The clinoptilolite-based Biosensors for L-arginine demonstrated short response time, high operational stability (a coefficient of variations reached 0.74%), their lifetime exceeded four months
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Effect of different modifications of BEA-zeolites on operational characteristics of conductometric Biosensor
Materials Science and Engineering: C, 2012Co-Authors: I. S. Kucherenko, Esin Soy, Oleksandr O. Soldatkin, Burcu Akata, Alexey P. Soldatkin, Nicole Jaffrezic-renault, K. Kirdeciler, S. Ozturk, Sergei V. DzyadevychAbstract:Effect of different modifications of zeolite Na+-BEA on working characteristics of urease-based conductometric Biosensor was studied. As the Biosensor sensitive elements were used bioselective membranes based on urease and various zeolites immobilised with bovine serum albumin on the surface of conductometric transducers. Influence of zeolites on sensitivity of urea Biosensor was investigated as well as reproducibility of Biosensor signal and reproducibility of activity of the bioselective element after different variants of urease immobilisation on the surface of conductometric transducer. The Biosensors based on zeolites (NH4+-BEA 30 and H+-BEA 30) were shown to be the most sensitive. Concentration of these zeolites in the bioselective membrane was optimized. Use of zeolites modified with methyl viologen and silver was ascertained to be of no prospect for urea conductometric Biosensors. It was demonstrated that characteristics of urea Biosensors can be regulated, varying zeolites modifications and their concentrations in bioselective membranes.
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Influence of composition of zeolite/enzyme nanobiocomposites on analytical characteristics of urea Biosensor based on ion-selective field-effect transistors
Sensor Letters, 2011Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Burcu Akata, Alexey P. Soldatkin, Abdelhamid Errachid, Nicole Jaffrezic-renault, Sergei V. DzyadevychAbstract:Zeolite/enzyme nanobiocomposites of different compositions were tested in this work for the improvement of Biosensor analytical characteristics. The bioselective element based on urease immobilized by cross-linking with glutaraldehyde was used as a model. The working characteristics of Biosensors based on various zeolite/enzyme nanocomposites were examined and compared with those of urease-based Biosensors. An optimal concentration of zeolytes beta (BEA) in bioselective elements is determined to be 1.5%. It ensures as wide linear range of measurement without remarkable loss in Biosensor sensitivity to urea. The BEA zeolite-based Biosensors were shown to have better working parameters in comparison with those based on zeolites A (LTA). A decrease in Biosensor sensitivity to heavy metal ions was demonstrated for all zeolites used, which testifies to probable increase in stability of urea measurement in real environmental samples.
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conductometric enzyme Biosensors based on natural zeolite clinoptilolite for urea determination
Materials Science and Engineering: C, 2011Co-Authors: O Y Saiapina, V M Pyeshkova, O O Soldatki, V G Melnik, Akata Kurc, Alai Walcarius, Sergei V. Dzyadevych, Nicole JaffrezicrenaulAbstract:Abstract Highly sensitive conductometric urea Biosensors were developed by exploiting the successful combination of ammonium-sieving and ion exchange properties of clinoptilolite, with a unique biorecognition capacity of urease. To optimize the performance of urea Biosensors based on clinoptilolite, the dependences of their analytical signals on pH, buffer capacity and ionic strength of phosphate buffer solution (PBS) were studied. Optimum pH for urea Biosensors was found within the range of pH 6.0–7.0. The dependences of Biosensors responses on buffer capacity and ionic strength of PBS were of the same profile as those obtained for the urea Biosensor which was not modified with clinoptilolite. Analytical characteristics of urea Biosensors based on clinoptilolite were evaluated by determination of the sensitivity, linear and dynamic ranges, detection limit, the apparent Michaelis–Menten constant and the response time. The optimum features in terms of sensitivity, dynamic range, and detection limit (20.36 μS/mM, 0–64 mM, and 10 −6 M, respectively) were found for the urea Biosensor, based on a primary layer of clinoptilolite followed by a secondary layer of urease and clinoptilolite in a single bioselective membrane. The apparent Michaelis–Menten constants K m for the developed urea Biosensors based on clinoptilolite varied from 2.73 to 5.67 mM. These values differed significantly from the value of K m for the urea Biosensor which was not modified with zeolite (1.89 mM). All types of zeolite-modified Biosensors showed high operational and storage stability.
Junwei Di - One of the best experts on this subject based on the ideXlab platform.
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fabrication of reagentless glucose Biosensors a comparison of mono enzyme god and bienzyme god hrp systems
Sensors and Actuators B-chemical, 2010Co-Authors: Ming Gu, Yifeng Tu, Jianwen Wang, Junwei DiAbstract:Abstract Glucose oxidase (GOD) and horseradish peroxidase (HRP), entrapped alone and simultaneously in silica sol–gel (SG) network on gold nanoparticles (GNPs) modified indium tin oxide (ITO) electrode, were used to fabricate mono-enzyme GOD and bienzyme GOD–HRP glucose Biosensors. The optimal conditions for the construction and the analytical performances of the Biosensors were studied and compared. The optimal GOD concentration in mixed solution for the mono-enzyme and bienzyme glucose Biosensors was about 250 U/mL, and the optimal GOD/HRP ratio was approximately 2 for the bienzyme glucose Biosensors. Amperometric response of glucose was evaluated by holding the Biosensors at 0.1 V (versus SCE). The linear ranges of detection for glucose were between 0.05–4.0 mmol/L and 0.02–3.2 mmol/L, respectively. The sensitivity of the bienzyme glucose Biosensor was approximately 2.4-fold higher than that of mono-enzyme glucose Biosensor. Both glucose Biosensors showed rapid response, high selectivity and long-term stability.
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Fabrication of reagentless glucose Biosensors: A comparison of mono-enzyme GOD and bienzyme GOD–HRP systems
Sensors and Actuators B-chemical, 2010Co-Authors: Ming Gu, Yifeng Tu, Jianwen Wang, Junwei DiAbstract:Abstract Glucose oxidase (GOD) and horseradish peroxidase (HRP), entrapped alone and simultaneously in silica sol–gel (SG) network on gold nanoparticles (GNPs) modified indium tin oxide (ITO) electrode, were used to fabricate mono-enzyme GOD and bienzyme GOD–HRP glucose Biosensors. The optimal conditions for the construction and the analytical performances of the Biosensors were studied and compared. The optimal GOD concentration in mixed solution for the mono-enzyme and bienzyme glucose Biosensors was about 250 U/mL, and the optimal GOD/HRP ratio was approximately 2 for the bienzyme glucose Biosensors. Amperometric response of glucose was evaluated by holding the Biosensors at 0.1 V (versus SCE). The linear ranges of detection for glucose were between 0.05–4.0 mmol/L and 0.02–3.2 mmol/L, respectively. The sensitivity of the bienzyme glucose Biosensor was approximately 2.4-fold higher than that of mono-enzyme glucose Biosensor. Both glucose Biosensors showed rapid response, high selectivity and long-term stability.
Alexey P. Soldatkin - One of the best experts on this subject based on the ideXlab platform.
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Nano- and microsized zeolites as a perspective material for potentiometric Biosensors creation
Nanoscale Research Letters, 2015Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Nicole Jaffrezic-renault, Florence Lagarde, Margaryta K. Shelyakina, Valentyna Arkhypova, Salih Kaan Kirdeciler, Berna Ozansoy Kasap, Burcu Akata Kurc, Alexey P. SoldatkinAbstract:A number of potentiometric Biosensors based on coimmobilization of enzymes with different types of zeolite on pH-ion-sensitive field-effect transistor (ISFET) have been developed. Their working characteristics have been determined and compared. It was shown that clinoptilolite and zeolite Beta polymorph A (BEA) are more promising for creating Biosensors than zeolite A. Changing the concentration of zeolite BEA in membranes, it is possible to extend the Biosensor linear measurement range. The two-layer method of deposition of the enzyme with clinoptilolite was found to provide a significant increase in the Biosensor sensitivity to substrates, whereas thermal modification of the zeolite BEA crystals can improve analytical characteristics of potentiometric Biosensors for detection of toxic substances. These results show that it is possible to regulate the ISFET characteristics for different enzyme-based Biosensors by tailoring the electrode surfaces via different zeolites. This makes zeolites strong candidates for integration into Biosensors as ISFET modifiers.
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Effect of different modifications of BEA-zeolites on operational characteristics of conductometric Biosensor
Materials Science and Engineering: C, 2012Co-Authors: I. S. Kucherenko, Esin Soy, Oleksandr O. Soldatkin, Burcu Akata, Alexey P. Soldatkin, Nicole Jaffrezic-renault, K. Kirdeciler, S. Ozturk, Sergei V. DzyadevychAbstract:Effect of different modifications of zeolite Na+-BEA on working characteristics of urease-based conductometric Biosensor was studied. As the Biosensor sensitive elements were used bioselective membranes based on urease and various zeolites immobilised with bovine serum albumin on the surface of conductometric transducers. Influence of zeolites on sensitivity of urea Biosensor was investigated as well as reproducibility of Biosensor signal and reproducibility of activity of the bioselective element after different variants of urease immobilisation on the surface of conductometric transducer. The Biosensors based on zeolites (NH4+-BEA 30 and H+-BEA 30) were shown to be the most sensitive. Concentration of these zeolites in the bioselective membrane was optimized. Use of zeolites modified with methyl viologen and silver was ascertained to be of no prospect for urea conductometric Biosensors. It was demonstrated that characteristics of urea Biosensors can be regulated, varying zeolites modifications and their concentrations in bioselective membranes.
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Influence of composition of zeolite/enzyme nanobiocomposites on analytical characteristics of urea Biosensor based on ion-selective field-effect transistors
Sensor Letters, 2011Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Burcu Akata, Alexey P. Soldatkin, Abdelhamid Errachid, Nicole Jaffrezic-renault, Sergei V. DzyadevychAbstract:Zeolite/enzyme nanobiocomposites of different compositions were tested in this work for the improvement of Biosensor analytical characteristics. The bioselective element based on urease immobilized by cross-linking with glutaraldehyde was used as a model. The working characteristics of Biosensors based on various zeolite/enzyme nanocomposites were examined and compared with those of urease-based Biosensors. An optimal concentration of zeolytes beta (BEA) in bioselective elements is determined to be 1.5%. It ensures as wide linear range of measurement without remarkable loss in Biosensor sensitivity to urea. The BEA zeolite-based Biosensors were shown to have better working parameters in comparison with those based on zeolites A (LTA). A decrease in Biosensor sensitivity to heavy metal ions was demonstrated for all zeolites used, which testifies to probable increase in stability of urea measurement in real environmental samples.
Oleksandr O. Soldatkin - One of the best experts on this subject based on the ideXlab platform.
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Nano- and microsized zeolites as a perspective material for potentiometric Biosensors creation
Nanoscale Research Letters, 2015Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Nicole Jaffrezic-renault, Florence Lagarde, Margaryta K. Shelyakina, Valentyna Arkhypova, Salih Kaan Kirdeciler, Berna Ozansoy Kasap, Burcu Akata Kurc, Alexey P. SoldatkinAbstract:A number of potentiometric Biosensors based on coimmobilization of enzymes with different types of zeolite on pH-ion-sensitive field-effect transistor (ISFET) have been developed. Their working characteristics have been determined and compared. It was shown that clinoptilolite and zeolite Beta polymorph A (BEA) are more promising for creating Biosensors than zeolite A. Changing the concentration of zeolite BEA in membranes, it is possible to extend the Biosensor linear measurement range. The two-layer method of deposition of the enzyme with clinoptilolite was found to provide a significant increase in the Biosensor sensitivity to substrates, whereas thermal modification of the zeolite BEA crystals can improve analytical characteristics of potentiometric Biosensors for detection of toxic substances. These results show that it is possible to regulate the ISFET characteristics for different enzyme-based Biosensors by tailoring the electrode surfaces via different zeolites. This makes zeolites strong candidates for integration into Biosensors as ISFET modifiers.
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Application of ammonium-selective zeolite for enhancement of conductometric bi-enzyme Biosensor for L-arginine detection
Sensorna elektronìka ì mìkrosistemnì tehnologìï = Sensor Electronics and Microsystem Technologies, 2014Co-Authors: O Y Saiapina, Oleksandr O. Soldatkin, V M Pyeshkova, V G Melnik, Alai Walcarius, Nicole Jaffrezic-renault, N. J. Matsishin, Sergei V. DzyadevychAbstract:L-arginine conductometric Biosensors were developed on the basis of arginase and ure¬ase cross-linked by glutaraldehyde in a single bioselective membrane and modified with clinoptilo¬lite. The clinoptilolite intrinsic properties helpful for conductometric detection of L-arginine were investigated using three approaches to the creation of zeolite-containing enzymatic membranes. The developed Biosensors were compared with the L-arginine Biosensor, not modified with clinoptilolite, for the sensitivity, linear and dynamic range, detection limit, response time, operational and storage stability in L-arginine analysis. It was shown that the incorporation of ammonium-selective zeolite to the bioselective membrane of L-arginine Biosensor allows increasing the Biosensor sensitivity when applying all proposed approaches to the formation of zeolite-containing biomembranes. In addition, excellent values of both detection limit and linear range (1.0×10-5 M and 0.01–6 mM, respectively) were achieved for the Biosensor based on arginase, urease and zeolite distributed in a single bioselec-tive layer. The clinoptilolite-based Biosensors for L-arginine demonstrated short response time, high operational stability (a coefficient of variations reached 0.74%), their lifetime exceeded four months
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Effect of different modifications of BEA-zeolites on operational characteristics of conductometric Biosensor
Materials Science and Engineering: C, 2012Co-Authors: I. S. Kucherenko, Esin Soy, Oleksandr O. Soldatkin, Burcu Akata, Alexey P. Soldatkin, Nicole Jaffrezic-renault, K. Kirdeciler, S. Ozturk, Sergei V. DzyadevychAbstract:Effect of different modifications of zeolite Na+-BEA on working characteristics of urease-based conductometric Biosensor was studied. As the Biosensor sensitive elements were used bioselective membranes based on urease and various zeolites immobilised with bovine serum albumin on the surface of conductometric transducers. Influence of zeolites on sensitivity of urea Biosensor was investigated as well as reproducibility of Biosensor signal and reproducibility of activity of the bioselective element after different variants of urease immobilisation on the surface of conductometric transducer. The Biosensors based on zeolites (NH4+-BEA 30 and H+-BEA 30) were shown to be the most sensitive. Concentration of these zeolites in the bioselective membrane was optimized. Use of zeolites modified with methyl viologen and silver was ascertained to be of no prospect for urea conductometric Biosensors. It was demonstrated that characteristics of urea Biosensors can be regulated, varying zeolites modifications and their concentrations in bioselective membranes.
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Influence of composition of zeolite/enzyme nanobiocomposites on analytical characteristics of urea Biosensor based on ion-selective field-effect transistors
Sensor Letters, 2011Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Burcu Akata, Alexey P. Soldatkin, Abdelhamid Errachid, Nicole Jaffrezic-renault, Sergei V. DzyadevychAbstract:Zeolite/enzyme nanobiocomposites of different compositions were tested in this work for the improvement of Biosensor analytical characteristics. The bioselective element based on urease immobilized by cross-linking with glutaraldehyde was used as a model. The working characteristics of Biosensors based on various zeolite/enzyme nanocomposites were examined and compared with those of urease-based Biosensors. An optimal concentration of zeolytes beta (BEA) in bioselective elements is determined to be 1.5%. It ensures as wide linear range of measurement without remarkable loss in Biosensor sensitivity to urea. The BEA zeolite-based Biosensors were shown to have better working parameters in comparison with those based on zeolites A (LTA). A decrease in Biosensor sensitivity to heavy metal ions was demonstrated for all zeolites used, which testifies to probable increase in stability of urea measurement in real environmental samples.
Nicole Jaffrezic-renault - One of the best experts on this subject based on the ideXlab platform.
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Nano- and microsized zeolites as a perspective material for potentiometric Biosensors creation
Nanoscale Research Letters, 2015Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Nicole Jaffrezic-renault, Florence Lagarde, Margaryta K. Shelyakina, Valentyna Arkhypova, Salih Kaan Kirdeciler, Berna Ozansoy Kasap, Burcu Akata Kurc, Alexey P. SoldatkinAbstract:A number of potentiometric Biosensors based on coimmobilization of enzymes with different types of zeolite on pH-ion-sensitive field-effect transistor (ISFET) have been developed. Their working characteristics have been determined and compared. It was shown that clinoptilolite and zeolite Beta polymorph A (BEA) are more promising for creating Biosensors than zeolite A. Changing the concentration of zeolite BEA in membranes, it is possible to extend the Biosensor linear measurement range. The two-layer method of deposition of the enzyme with clinoptilolite was found to provide a significant increase in the Biosensor sensitivity to substrates, whereas thermal modification of the zeolite BEA crystals can improve analytical characteristics of potentiometric Biosensors for detection of toxic substances. These results show that it is possible to regulate the ISFET characteristics for different enzyme-based Biosensors by tailoring the electrode surfaces via different zeolites. This makes zeolites strong candidates for integration into Biosensors as ISFET modifiers.
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Comparison of carboxypeptidase Y and thermolysin for ochratoxin A electrochemical biosensing
Analytical Methods, 2015Co-Authors: Fatma Dridi, Nicole Jaffrezic-renault, Mouna Marrakchi, Mohamed Gargouri, Joelle Saulnier, Florence LagardeAbstract:Herein, carboxypeptidase Y (CPY) and thermolysin (TLN) were compared as sensing elements to develop an original Biosensor for the direct detection of ochratoxin A (OTA) in olive oil. Electrochemical detection of OTA was performed using Biosensors containing either CPY or TLN immobilized through glutaraldehyde vapor cross-linking onto gold interdigitated microelectrodes. Different parameters affecting Biosensor sensitivity towards OTA were first optimized. TLN and CPY exhibited an optimal activity under the same conditions: 35 min cross-linking time, working pH of 7 and temperature of 25 degrees C. TLN and CPY Biosensors exhibited comparable analytical performances. The conductometric response of both modified electrodes was linear up to 75 mu M. The limits of detection were also very similar (1 mu M for the CPY Biosensor and 0.7 mu M for the TLN Biosensor). For both enzymes, initial rate vs. OTA concentration plots could be described by hyperbolic curves consistent with the Michaelis-Menten model. K-M(app) and V-max(app), deduced from these curves, were 26 mu M and 3.3 mu S min(-1) respectively for the TLN Biosensor. The Biosensors signal was reproducible, relative standard deviations calculated from three consecutive measurements of standards in the 1-75 mu M range, being lower than 5%. The signals were also very stable over a 30 days period when Biosensors were stored at 4 degrees C in 20 mM phosphate buffer between two measurements. The TLN Biosensor was further evaluated for OTA determination in spiked olive oil samples. Recovery values were close to 100% demonstrating the suitability of this method for OTA screening in olive oil. Interestingly, OTA concentrations could be determined without pretreatment of the sample and no matrix effect was observed.
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Application of ammonium-selective zeolite for enhancement of conductometric bi-enzyme Biosensor for L-arginine detection
Sensorna elektronìka ì mìkrosistemnì tehnologìï = Sensor Electronics and Microsystem Technologies, 2014Co-Authors: O Y Saiapina, Oleksandr O. Soldatkin, V M Pyeshkova, V G Melnik, Alai Walcarius, Nicole Jaffrezic-renault, N. J. Matsishin, Sergei V. DzyadevychAbstract:L-arginine conductometric Biosensors were developed on the basis of arginase and ure¬ase cross-linked by glutaraldehyde in a single bioselective membrane and modified with clinoptilo¬lite. The clinoptilolite intrinsic properties helpful for conductometric detection of L-arginine were investigated using three approaches to the creation of zeolite-containing enzymatic membranes. The developed Biosensors were compared with the L-arginine Biosensor, not modified with clinoptilolite, for the sensitivity, linear and dynamic range, detection limit, response time, operational and storage stability in L-arginine analysis. It was shown that the incorporation of ammonium-selective zeolite to the bioselective membrane of L-arginine Biosensor allows increasing the Biosensor sensitivity when applying all proposed approaches to the formation of zeolite-containing biomembranes. In addition, excellent values of both detection limit and linear range (1.0×10-5 M and 0.01–6 mM, respectively) were achieved for the Biosensor based on arginase, urease and zeolite distributed in a single bioselec-tive layer. The clinoptilolite-based Biosensors for L-arginine demonstrated short response time, high operational stability (a coefficient of variations reached 0.74%), their lifetime exceeded four months
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Effect of different modifications of BEA-zeolites on operational characteristics of conductometric Biosensor
Materials Science and Engineering: C, 2012Co-Authors: I. S. Kucherenko, Esin Soy, Oleksandr O. Soldatkin, Burcu Akata, Alexey P. Soldatkin, Nicole Jaffrezic-renault, K. Kirdeciler, S. Ozturk, Sergei V. DzyadevychAbstract:Effect of different modifications of zeolite Na+-BEA on working characteristics of urease-based conductometric Biosensor was studied. As the Biosensor sensitive elements were used bioselective membranes based on urease and various zeolites immobilised with bovine serum albumin on the surface of conductometric transducers. Influence of zeolites on sensitivity of urea Biosensor was investigated as well as reproducibility of Biosensor signal and reproducibility of activity of the bioselective element after different variants of urease immobilisation on the surface of conductometric transducer. The Biosensors based on zeolites (NH4+-BEA 30 and H+-BEA 30) were shown to be the most sensitive. Concentration of these zeolites in the bioselective membrane was optimized. Use of zeolites modified with methyl viologen and silver was ascertained to be of no prospect for urea conductometric Biosensors. It was demonstrated that characteristics of urea Biosensors can be regulated, varying zeolites modifications and their concentrations in bioselective membranes.
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Influence of composition of zeolite/enzyme nanobiocomposites on analytical characteristics of urea Biosensor based on ion-selective field-effect transistors
Sensor Letters, 2011Co-Authors: Oleksandr O. Soldatkin, Esin Soy, Burcu Akata, Alexey P. Soldatkin, Abdelhamid Errachid, Nicole Jaffrezic-renault, Sergei V. DzyadevychAbstract:Zeolite/enzyme nanobiocomposites of different compositions were tested in this work for the improvement of Biosensor analytical characteristics. The bioselective element based on urease immobilized by cross-linking with glutaraldehyde was used as a model. The working characteristics of Biosensors based on various zeolite/enzyme nanocomposites were examined and compared with those of urease-based Biosensors. An optimal concentration of zeolytes beta (BEA) in bioselective elements is determined to be 1.5%. It ensures as wide linear range of measurement without remarkable loss in Biosensor sensitivity to urea. The BEA zeolite-based Biosensors were shown to have better working parameters in comparison with those based on zeolites A (LTA). A decrease in Biosensor sensitivity to heavy metal ions was demonstrated for all zeolites used, which testifies to probable increase in stability of urea measurement in real environmental samples.