The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Serge Cosnier - One of the best experts on this subject based on the ideXlab platform.
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polycrystalline bismuth oxide films for development of Amperometric Biosensor for phenolic compounds
Biosensors and Bioelectronics, 2009Co-Authors: Dan Shan, Jing Zhang, Huaiguo Xue, Yongcai Zhang, Serge Cosnier, Shounian DingAbstract:Abstract An attractive biocomposite based on polycrystalline bismuth oxide (BiO x ) film and polyphenol oxidase (PPO) was proposed for the construction of a mediator-free Amperometric Biosensor for phenolic compounds in environmental water samples. The phenolic Biosensor could be easily achieved by casting the biocomposite on the surface of glassy carbon electrode (GCE) via the cross-linking step by glutaraldehyde. The laboratory-prepared bismuth oxide semiconductor was polymorphism. Its hydrophilicity provided a favorable microenvironment for retaining the biological activity of the immobilized protein. The parameters of the fabrication process and the various experimental variables for the enzyme electrode were optimized. The proposed PPO/BiO x Biosensor provided a linear response to catechol over a concentration range of 4 × 10 −9 M to 1.5 × 10 −5 M with a dramatically developed sensitivity of 11.3 A M −1 cm −2 and a detection limit of 1 × 10 −9 M based on S/N = 3. In addition, the PPO/BiO x biocomposite was characterized by scanning electron microscope (SEM), Fourier transform infrared spectra (FTIR) and rotating disk electrode voltammetry.
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development of Amperometric Biosensor for glucose based on a novel attractive enzyme immobilization matrix calcium carbonate nanoparticles
Biosensors and Bioelectronics, 2007Co-Authors: Dan Shan, Huaiguo Xue, Mingjuan Zhu, Serge CosnierAbstract:Abstract Calcium carbonate nanoparticles (nano-CaCO 3 ) may be a promising material for enzyme immobilization owing to their high biocompatibility, large specific surface area and their aggregation properties. This attractive material was exploited for the mild immobilization of glucose oxidase (GOD) in order to develop glucose Amperometric Biosensor. The GOD/nano-CaCO 3 -based sensor exhibited a marked improvement in thermal stability compared to other glucose Biosensors based on inorganic host matrixes. Amperometric detection of glucose was evaluated by holding the modified electrode at 0.60 V (versus SCE) in order to oxidize the hydrogen peroxide generated by the enzymatic reaction. The Biosensor exhibited a rapid response (6 s), a low detection limit (0.1 μM), a wide linear range of 0.001–12 mM, a high sensitivity (58.1 mA cm −2 M −1 ), as well as a good operational and storage stability. In addition, optimization of the Biosensor construction, the effects of the applied potential as well as common interfering compounds on the Amperometric response of the sensor were investigated and discussed herein.
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laccase immobilization in redox active layered double hydroxides a reagentless Amperometric Biosensor
Biosensors and Bioelectronics, 2007Co-Authors: Christine Mousty, Laetitia Vieille, Serge CosnierAbstract:Abstract This paper describes a new system for Amperometric determination of dissolved oxygen and its application for the detection of anionic toxic substances, which are known as enzyme inhibitors. This Biosensor is based on the co-immobilization of laccase from Trametes versicolor and a redox active layered double hydroxide [Zn–Cr–ABTS] on a glassy carbon electrode. The electrochemical transduction step corresponds to the electrocatalytic reduction of O 2 at 0.2 V by laccase as catalyst and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as mediator. Such device provides a fast and a sensitive response for dissolved oxygen determination between 6 × 10 −8 and 4 × 10 −6 M and very low detection limits for azide (5.5 nM), fluoride (6.9 nM) and cyanide (6.2 nM).
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Amperometric phenol Biosensor based on laponite clay chitosan nanocomposite matrix
Biosensors and Bioelectronics, 2007Co-Authors: Quan Fan, Dan Shan, Huaiguo Xue, Serge CosnierAbstract:A novel strategy to fabricate an Amperometric Biosensor for phenol determination based on chitosan/laponite nanocomposite matrix was described. The composite film was used to immobilize PPO on the surface of a glassy carbon electrode. Chitosan was utilized to improve the analytical performance of the pure clay-modified bioelectrode. The Biosensor exhibited a series of properties: good affinity to its substrate (the apparent Michaelis-Menten constant for the sensor was found to be 0.16 mM), high sensitivity (674 mA M(-1)cm(-2) for catechol) and remarkable long-term stability in storage (it retains 88% of the original activity after 60 days). In addition, optimization of the Biosensor construction as well as effects of experimental variables such as pH, operating potential and temperature on the Amperometric response of the sensor were discussed.
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Protease Amperometric sensor.
Analytical chemistry, 2006Co-Authors: Rodica E. Ionescu, Serge Cosnier, Robert S. MarksAbstract:An Amperometric Biosensor for the detection of trypsin was developed. The latter was based on a two-layer configuration, namely, a polymer−glucose oxidase inner layer and a gelatin outer layer. In ...
Christine Mousty - One of the best experts on this subject based on the ideXlab platform.
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galactose oxidase prussian blue based Biosensors
Electroanalysis, 2015Co-Authors: Franck Charmantray, Nadia Touisni, Laurence Hecquet, Thierry Noguer, Christine Mousty, Christine MoustyAbstract:This paper describes the development of an Amperometric Biosensor based on galactose oxidase (GAOx) immobilization within a laponite clay film deposited on Carbon Screen-Printed Electrodes modified by electrodeposited Prussian Blue and coated with poly-(O-phenylenediamine) (PPD/PB/CSPEs). Amperometric performances of GAOx@laponite/PPD/PB/CSPEs bioelectrodes were determined using several GAOx substrates. Using these modified electrodes the reduction of enzymatically generated hydrogen peroxide was performed at −0.2 V vs. Ag-AgCl. In an initial attempt, E.Coli transketolase activity on its immobilized form was followed using a bienzymatic GAOx-TK Biosensor.
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laccase immobilization in redox active layered double hydroxides a reagentless Amperometric Biosensor
Biosensors and Bioelectronics, 2007Co-Authors: Christine Mousty, Laetitia Vieille, Serge CosnierAbstract:Abstract This paper describes a new system for Amperometric determination of dissolved oxygen and its application for the detection of anionic toxic substances, which are known as enzyme inhibitors. This Biosensor is based on the co-immobilization of laccase from Trametes versicolor and a redox active layered double hydroxide [Zn–Cr–ABTS] on a glassy carbon electrode. The electrochemical transduction step corresponds to the electrocatalytic reduction of O 2 at 0.2 V by laccase as catalyst and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as mediator. Such device provides a fast and a sensitive response for dissolved oxygen determination between 6 × 10 −8 and 4 × 10 −6 M and very low detection limits for azide (5.5 nM), fluoride (6.9 nM) and cyanide (6.2 nM).
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specific determination of as v by an acid phosphatase polyphenol oxidase Biosensor
Analytical Chemistry, 2006Co-Authors: Serge Cosnier, Christine Mousty, Xiurong Yang, Serge Cosnier, Christine Mousty, Shaojun DongAbstract:An original Amperometric Biosensor based on the simultaneous entrapment of acid phosphatase (AcP) and polyphenol oxidase (PPO) into anionic clays (layered double hydroxides) was developed for the specific detection of As(V). The functioning principle of the bienzyme electrode consisted of the successive hydrolysis of phenyl phosphate into phenol by AcP, followed by the oxidation of phenol into o-quinone by PPO. The phenyl phosphate concentration was, thus, monitored by potentiostating the Biosensor at −0.2 V vs Ag/AgCl to detect Amperometrically the generated quinone. The detection of As(V) was based on its inhibitory effect on AcP activity toward the hydrolysis of phenyl phosphate into phenol. The As(V) can be specifically determined in pH 6.0 acetate buffer without any interferences of As(III) or phosphate, the detection limit being 2 nM or 0.15 ppb after an incubation step for 20 min.
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subnanomolar cyanide detection at polyphenol oxidase clay Biosensors
Analytical Chemistry, 2004Co-Authors: Dan Shan, Christine Mousty, Serge CosnierAbstract:A novel, inexpensive, and simple Amperometric Biosensor based on immobilization of polyphenol oxidase (PPO) into Zn−Al layered double hydroxides, also called anionic clays, is applied for determination of cyanide. The detection of cyanide was performed via its inhibiting action on the PPO electrode. Measurement was carried out with 3,4-dihydroxyphenylacetic acid as enzyme substrate, the enzymatically generated quinoid products being electroreduced at −0.2 V. An extremely sensitive detection limit (0.1 nM) was obtained for cyanide. Enzyme immobilization into an anionic exchanger clay seems to cause an increase in cyanide inhibition effects because of anion accumulation in the clay matrix.
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a new polyphenol oxidase Biosensor mediated by azure b in laponite clay matrix
Electroanalysis, 2003Co-Authors: Dan Shan, Christine Mousty, Serge Cosnier, Dan Shan, Christine Mousty, Serge CosnierAbstract:Amperometric Biosensor based on the entrapment of polyphenol oxidase within a laponite clay coating and cross-linked by glutaraldehyde is described for catechol detection. Laponite provides a hydrophilic enzyme surrounding increasing the long term stability of the Biosensor compared to the corresponding Biosensors obtained by chemical cross-linking of PPO with glutaraldehyde. Azure B, a cationic dye exchanged within the clay matrix, is used as an electron shuttle allowing the mediated detection of phenol derivatives at −0.05 V. The detection limits obtained with the optimized Biosensor configuration for catechol, p-cresol and phenol are 1, 1 and 17 nM, respectively.
P G Zambonin - One of the best experts on this subject based on the ideXlab platform.
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electrosynthesized poly pyrrole poly 2 naphthol bilayer membrane as an effective anti interference layer for simultaneous determination of acethylcholine and choline by a dual electrode Amperometric Biosensor
Biosensors and Bioelectronics, 2006Co-Authors: Antonio Guerrieri, V Lattanzio, F Palmisano, P G ZamboninAbstract:Abstract Several neural diseases appear related to the neurotransmitter acethylcholine (ACh) and its metabolite choline (Ch) brain levels so that their simultaneous determination is essential. A cross-talk and interference free dual electrode Amperometric Biosensor for the simultaneous determination of both analytes has been developed. Acetylcholinesterase (AChE) and choline oxidase (ChO) were immobilized by glutaraldehyde co-crosslinking with bovine serum albumin. A very efficient rejection of electroactive interferents has been achieved by a novel electrosynthesized polymeric bilayer membrane composed by overoxidised poly(pyrrole) and poly(2-naphthol) films. Sensitivities towards several electroactive interferents ranged from ca. 0.04% (e.g. ascorbate) to ca. 0.3% (e.g. dopamine) of those relevant to ACh and Ch (11 and 15 μA/μM, respectively). Detection limits (at S/N = 3) in flow injection analysis were ca. 100 nM for both ACh and Ch at the ChO–AChE electrode and ca. 40 nM for Ch at the ChO sensor. Biosensor performances appear more than adequate for brain tissue homogenates and cerebrospinal fluids analysis where average levels in the low micromolar range are typically found.
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determination of choline in milk milk powder and soy lecithin hydrolysates by flow injection analysis and Amperometric detection with a choline oxidase based Biosensor
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Sandra Pati, Francesco Palmisano, Maurizio Quinto, P G ZamboninAbstract:A fast-response and interference-free Amperometric Biosensor based on choline oxidase immobilized onto an electropolymerized polypyrrole film for flow injection determination of choline in milk, milk powder, and soy lecithin hydrolysates is described. The sensor displayed an Imax value of 1.9 +/- 0.2 microA and an apparent Michaelis-Menten constant, k'M, equal to 1.75 +/- 0.07 mM. Detection limits of 0.12 microM could be obtained. Because even a slight deterioration of the anti-interference membrane can adversely affect measurement accuracy, a real time monitoring of the Biosensor selectivity has been achieved by a dual Pt electrode flow-through cell where the enzyme modified electrode is coupled to an enzyme-free electrode in a parallel configuration. Finally, bracketing technique (alternate injections of sample and standards) allows a two-point calibration to be performed in real-time, correcting for any drift in sensor response.
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simultaneous monitoring of glucose and lactate by an interference and cross talk free dual electrode Amperometric Biosensor based on electropolymerized thin films
Biosensors and Bioelectronics, 2000Co-Authors: Francesco Palmisano, Diego Centonze, R Rizzi, P G ZamboninAbstract:Abstract An interference and cross-talk free dual electrode Amperometric Biosensor integrated with a microdialysis sampling system is described, for simultaneous monitoring of glucose and lactate by flow injection analysis. The Biosensor is based on a conventional thin layer flow-through cell equipped with a Pt dual electrode (parallel configuration). Each Pt disk was modified by a composite bilayer consisting of an electrosynthesised overoxidized polypyrrole (PPYox) anti-interference membrane covered by an enzyme entrapping gel, obtained by glutaraldehyde co-crosslinking of glucose oxidase or lactate oxidase with bovine serum albumin. The advantages of covalent immobilization techniques were coupled with the excellent interference-rejection capabilities of PPYox. Ascorbate, cysteine, urate and paracetamol produced lactate or glucose bias in the low micromolar range; their responses were, however, completely suppressed when the sample was injected through the microdialysis unit. Under these operational conditions the flow injection responses for glucose and lactate were linear up to 100 and 20 mM with typical sensitivities of 9.9 (±0.1) and 7.2 (±0.1) nA/mM, respectively. The shelf-lifetime of the Biosensor was at least 2 months. The potential of the described Biosensor was demonstrated by the simultaneous determination of lactate and glucose in untreated tomato juice samples; results were in good agreement with those of a reference method.
Francesco Palmisano - One of the best experts on this subject based on the ideXlab platform.
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determination of choline in milk milk powder and soy lecithin hydrolysates by flow injection analysis and Amperometric detection with a choline oxidase based Biosensor
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Sandra Pati, Francesco Palmisano, Maurizio Quinto, P G ZamboninAbstract:A fast-response and interference-free Amperometric Biosensor based on choline oxidase immobilized onto an electropolymerized polypyrrole film for flow injection determination of choline in milk, milk powder, and soy lecithin hydrolysates is described. The sensor displayed an Imax value of 1.9 +/- 0.2 microA and an apparent Michaelis-Menten constant, k'M, equal to 1.75 +/- 0.07 mM. Detection limits of 0.12 microM could be obtained. Because even a slight deterioration of the anti-interference membrane can adversely affect measurement accuracy, a real time monitoring of the Biosensor selectivity has been achieved by a dual Pt electrode flow-through cell where the enzyme modified electrode is coupled to an enzyme-free electrode in a parallel configuration. Finally, bracketing technique (alternate injections of sample and standards) allows a two-point calibration to be performed in real-time, correcting for any drift in sensor response.
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an acetylcholinesterase choline oxidase based Amperometric Biosensor as a liquid chromatography detector for acetylcholine and choline determination in brain tissue homogenates
Analytical Chemistry, 2001Co-Authors: Antonio Guerrieri, Francesco PalmisanoAbstract:A liquid chromatography (LC) detector based on a fast response and sensitive bienzyme Amperometric Biosensor for acetylcholine (ACh) and choline (Ch) is described. The detector fabrication consisted of glutaraldehyde co-cross-linking of acetylcholinesterase and choline oxidase with bovine serum albumin on the Pt working electrode of a conventional thin-layer electrochemical flow cell. The influence of some experimental parameters (e.g., enzyme loading, thickness of the bienzyme layer, flow rate) on the detector characteristics has been studied in order to optimize the analyte response while minimizing band-broadening and distortion. A mobile phase consisting of a phosphate buffer (I, 0.1 M; pH, 6.5) containing 5 mM sodium hexane sulfonate and 10 mM tetramethylammonium phosphate was found to give very satisfactory resolution and peak shape in ion-pair, reversed-phase LC. Linear responses were observed over at least four decades and absolute detection limits (at a signal-to-noise ratio of 3) were 12 and 27 ...
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simultaneous monitoring of glucose and lactate by an interference and cross talk free dual electrode Amperometric Biosensor based on electropolymerized thin films
Biosensors and Bioelectronics, 2000Co-Authors: Francesco Palmisano, Diego Centonze, R Rizzi, P G ZamboninAbstract:Abstract An interference and cross-talk free dual electrode Amperometric Biosensor integrated with a microdialysis sampling system is described, for simultaneous monitoring of glucose and lactate by flow injection analysis. The Biosensor is based on a conventional thin layer flow-through cell equipped with a Pt dual electrode (parallel configuration). Each Pt disk was modified by a composite bilayer consisting of an electrosynthesised overoxidized polypyrrole (PPYox) anti-interference membrane covered by an enzyme entrapping gel, obtained by glutaraldehyde co-crosslinking of glucose oxidase or lactate oxidase with bovine serum albumin. The advantages of covalent immobilization techniques were coupled with the excellent interference-rejection capabilities of PPYox. Ascorbate, cysteine, urate and paracetamol produced lactate or glucose bias in the low micromolar range; their responses were, however, completely suppressed when the sample was injected through the microdialysis unit. Under these operational conditions the flow injection responses for glucose and lactate were linear up to 100 and 20 mM with typical sensitivities of 9.9 (±0.1) and 7.2 (±0.1) nA/mM, respectively. The shelf-lifetime of the Biosensor was at least 2 months. The potential of the described Biosensor was demonstrated by the simultaneous determination of lactate and glucose in untreated tomato juice samples; results were in good agreement with those of a reference method.
Mykhailo Gonchar - One of the best experts on this subject based on the ideXlab platform.
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bi enzyme l arginine selective Amperometric Biosensor based on ammonium sensing polyaniline modified electrode
Biosensors and Bioelectronics, 2012Co-Authors: Nataliya Stasyuk, Mykhailo Gonchar, Oleh Smutok, G Z Gayda, Yevgen KovalchukAbstract:Abstract A novel l -arginine-selective Amperometric bi-enzyme Biosensor based on recombinant human arginase I isolated from the gene-engineered strain of methylotrophic yeast Hansenula polymorpha and commercial urease is described. The biosensing layer was placed onto a polyaniline–Nafion composite platinum electrode and covered with a calcium alginate gel. The developed sensor revealed a good selectivity to l -arginine. The sensitivity of the Biosensor was 110±1.3 nA/(mM mm 2 ) with the apparent Michaelis–Menten constant ( K M app ) derived from an l -arginine ( l -Arg) calibration curve of 1.27±0.29 mM. A linear concentration range was observed from 0.07 to 0.6 mM, a limit of detection being 0.038 mM and a response time — 10 s. The developed Biosensor demonstrated good storage stability. A laboratory prototype of the proposed Amperometric Biosensor was applied to the samples of three commercial pharmaceuticals (“Tivortin”, “Cytrarginine”, “Aminoplazmal 10% E”) for l -Arg testing. The obtained l -Arg-content values correlated well with those declared by producers.
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isolation and characterization of mutated alcohol oxidases from the yeast hansenula polymorpha with decreased affinity toward substrates and their use as selective elements of an Amperometric Biosensor
BMC Biotechnology, 2007Co-Authors: Kostyantyn V Dmytruk, Mykhailo Gonchar, Oleh Smutok, G Z Gayda, Wolfgang Schuhmann, Olena B Ryabova, Volodymyr Sibirny, Andriy A SibirnyAbstract:Accurate, rapid, and economic on-line analysis of ethanol is very desirable. However, available Biosensors achieve saturation at very low ethanol concentrations and thus demand the time and labour consuming procedure of sample dilution. Hansenula polymorpha (Pichia angusta) mutant strains resistant to allyl alcohol in methanol medium were selected. Such strains possessed decreased affinity of alcohol oxidase (AOX) towards methanol: the KM values for AOX of wild type and mutant strains CA2 and CA4 are shown to be 0.62, 2.48 and 1.10 mM, respectively, whereas Vmax values are increased or remain unaffected. The mutant AOX alleles from H. polymorpha mutants CA2 and CA4 were isolated and sequenced. Several point mutations in the AOX gene, mostly different between the two mutant alleles, have been identified. Mutant AOX forms were isolated and purified, and some of their biochemical properties were studied. An Amperometric Biosensor based on the mutated form of AOX from the strain CA2 was constructed and revealed an extended linear response to the target analytes, ethanol and formaldehyde, as compared to the sensor based on the native AOX. The described selection methodology opens up the possibility of isolating modified forms of AOX with further decreased affinity toward substrates without reduction of the maximal velocity of reaction. It can help in creation of improved ethanol Biosensors with a prolonged linear response towards ethanol in real samples of wines, beers or fermentation liquids.
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a novel l lactate selective Biosensor based on flavocytochrome b2 from methylotrophic yeast hansenula polymorpha
Biosensors and Bioelectronics, 2005Co-Authors: Oleh Smutok, Mykhailo Gonchar, G Z Gayda, Wolfgang SchuhmannAbstract:A novel Amperometric Biosensor highly selective to L-lactate has been developed using L-lactate-cytochrome c oxidoreductase (flavocytochrome b2) isolated for the first time from thermotolerant methylotrophic yeast Hansenula polymorpha as biorecognition element. Different immobilization methods and low-molecular free-diffusing redox mediators have been tested for optimising the electrochemical communication between the immobilized enzyme and the electrode surface. Moreover, the possibility of direct electron transfer from the reduced form of FCb2 to carbon electrodes has been evaluated. The bioanalytical properties of FCb2-based Biosensors, such as signal rise time, dynamic range, dependence of the sensor output on the pH value, the temperature and the storage stability were investigated, and the proposed Biosensor demonstrated a very fast response and a high sensitivity and selectivity for L-lactate determination.