Papers by Gennady Evtugyn
Talanta, Sep 1, 2014
New acetylcholinesterase (AChE) sensor based on Ag nanoparticles decorated with macrocyclic ligan... more New acetylcholinesterase (AChE) sensor based on Ag nanoparticles decorated with macrocyclic ligand has been developed and successfully used for highly sensitive detection of organophosphate and carbamate pesticides. AChE was immobilized by carbodiimide binding on carbon black (CB) layer deposited on a glassy carbon electrode. The addition of Ag nanoparticles decreased the working potential of the biosensor from 350 to 50 mV. The AChE sensor made it possible to detect 0.4 nM-0.2 μM of malaoxon, 0.2 nM-0.2 μM of paraoxon, 0.2 nM-2.0 μM of carbofuran and 10 nM-0.20 μM of aldicarb (limits of detection 0.1, 0.05, 0.1 and 10 nM, respectively) with 10 min incubation. The AChE sensor was tested for the detection of residual amounts of pesticides in spiked samples of peanut and grape juice. The protecting effect of new macrocyclic compounds bearing quaternary ammonia fragments was shown on the example of malaoxon inhibition.
Аналитика и контроль, 2022
Определение содержания галогенид-ионов в лекарственных препаратах и водах различного назначения п... more Определение содержания галогенид-ионов в лекарственных препаратах и водах различного назначения представляет собой актуальную задачу современной аналитической химии. В работе представлен твердоконтактный потенциометрический сенсор на основе стеклоуглеродного электрода, покрытого слоем электрополимеризованного анилина и суспензией наночастиц серебра в матрице производного тиакаликс[4]арена с концевыми пирокатехиновыми группами. Суспензию получали, химически восстанавливая ионы серебра тиакаликс[4]ареном и капельно наносили на слой полианилина. Сенсор демонстрировал потенциометрический отклик на хлорид-, бромид и йодид-ионы. Для одновременного определения йодид-и бромид ионов предложено использовать мультисенсорную систему из четырех электродов, отличающихся составом и объемом суспензии, наносимой на полимерную подложку полианилина. На выборке смесей йодид-и бромид-ионов показана возможность предсказания отклика на основе простой аддитивной модели. Аналогичным образом проводили одновременное определение обоих ионов в смесях произвольного состава. Мультисенсорная система была апробирована на определении йодид-ионов в йодсодержащих медицинских препаратов, а также йодид-и бромид-ионов в искусственных образцах минеральной воды. Методом сравнения выступала ионная хроматография. Сенсоры позволяют проводить определение от 0.1 мкМ до 10 мМ йодид-и бромид-ионов в смесях. Предложенный подход и твердоконтактные потенциометрические сенсоры могут найти применение в анализе ионного состава вод и контроля производства и хранения лекарственных препаратов.
Electroanalysis, Jul 16, 2015
Langmuir, Nov 9, 2009
Here we report the three-dimensional assembly of carbon nanotubes on the polyelectrolyte-coated l... more Here we report the three-dimensional assembly of carbon nanotubes on the polyelectrolyte-coated living Saccharomyces cerevisiae cells using the polyelectrolyte-mediated layer-by-layer approach. Synthetic polyelectrolytes poly(allylamine hydrochloride) and poly(sodium 4-styrenesulfonate) were layer-by-layer deposited on the surfaces of the yeast cells followed by the deposition of water-soluble oxidized multiwalled carbon nanotubes (MWNTs) and an additional outermost polyelectrolyte bilayer. This resulted in the fabrication of polyelectrolyte/nanotubes composite coatings on the cell walls of the yeast cells, which could be clearly seen using the conventional optical microscopy. Transmission and scanning electron microscopy was applied to further investigate the composite coatings. Viability of the encapsulated cells was confirmed using the intercellular esterase activity test. Finally, electrochemical studies using voltammetry and electrochemical impedance measurements were performed, indicating that the composite polyelectrolytes/MWNTs coatings sufficiently affect the electron mediation between the encapsulated yeast cells and the artificial electron acceptor, making it possible to distinguish between living and dead cells. The technique described here may find potential application in the development of microelectronic devices, core-shell and hollow composite microparticles, and electrochemical cell-based biosensors.
Journal of The Electrochemical Society, Dec 1, 2022
For the first time, the cumulative effect of changes in the concentration of methylene blue (MB),... more For the first time, the cumulative effect of changes in the concentration of methylene blue (MB), pillar[6]arene (P6), and DNA in MB electropolymerization performed by repeated cycling of the potential of a glassy carbon electrode modified with carbon black was described by construction of generalized linear models within the full factor experiment design. The proposed models of the currents and potentials of the peaks attributed to the monomeric and polymeric MB forms fully describe synergistic effect of the reaction mixture components and their contribution to the efficiency of electropolymerization and accumulation of the redox active layer on the electrode. The MB concentration exerted the biggest effect on the redox peak currents of the coating. DNA addition decreased the redox peak currents to a degree mostly pronounced for the high MB concentrations. The P6 addition significantly improved the conditions of the electron exchange and increased the redox peak currents, especially at low MB concentrations. The results obtained can find application for the optimization of the assembling conditions in the DNA sensors design.
CRC Press eBooks, Jan 6, 2023
Analytical Sciences/Supplements Proceedings of the Sixth Asian Conference on Analytical Sciences (ASIANALYSIS VI), 2001
Analytical Letters, Dec 8, 2021
Abstract A flow-through biosensor has been developed and manufactured by 3D printing from poly(la... more Abstract A flow-through biosensor has been developed and manufactured by 3D printing from poly(lactic acid). Uricase or tyrosinase were immobilized on the inner walls of the reactor cell and the concentrations of the reaction products, i.e., hydrogen peroxide in the case of uricase and quinone product of the tyrosine oxidation in the case of tyrosinase, were monitored in the amperometric mode. The screen-printed electrode modified with carbon black, pillar[5]arene and electropolymerized thionine and methylene blue was separated from the enzyme layer by 0.1 mm gap and used as a biosensor transducer. The components of the modifier layer exerted a synergetic effect and increased the cathodic current up to seven times compared to electrodes modified with individual components, increasing the sensitivity of the analysis. In the optimal conditions, biosensor allowed the determination of 1 × 10−7 to 1 × 10−5 M uric acid and 2 × 10−7 to 1 × 10−5 M tyrosine. The biosensors analyzed spiked samples of blood serum and urine and provided recoveries from 95 to 110%. Easy mounting of the flow-through cell and low cost of the replaceable parts make promising future application of the biosensor for routine clinical assays.
Frontiers in Chemistry, Nov 27, 2018
New solid-contact potentiometric sensors have been developed for hydrogen phosphate recognition o... more New solid-contact potentiometric sensors have been developed for hydrogen phosphate recognition on the basis of ionic liquids containing tetrasubstituted derivatives of thiacalix[4]arene in cone and 1,3-alternate conformations with trimethyl-and triethylammonium fragments at the lower rim substituents. The recognition of selected anions including carbonate, hydrogen phosphate, perchlorate, oxalate, picrate, and EDTA was conducted using electrochemical impedance spectroscopy with ferricyanide redox probe. For the potentiometric sensor assembling, the ionic liquids were stabilized by multiwalled carbon nanotubes and carbon black deposited on the glassy carbon electrode. The influence of support, steric factors and modification conditions on the sensor performance has been investigated. As was shown, potentiometric sensors developed make it possible to selectively determine hydrogen phosphate anion within the concentration range from 1 × 10 −2 to 1 × 10 −6 M and limit of detection of 2 × 10 −7 −1 × 10 −6 M with unbiased selectivity coefficients varied from 1.2 × 10 −1 to 1.0 × 10 −8 (carbonate, acetate, oxalate, succinate, glutharate, glycolate, and malonate anions).
Electroanalysis, Jun 28, 2013
An electrochemical aptasensor for ochratoxin A (OTA) detection has been developed on the base of ... more An electrochemical aptasensor for ochratoxin A (OTA) detection has been developed on the base of a gold electrode covered with electropolymerized neutral red and silver nanoparticles obtained by chemical reduction with macrocyclic ligands bearing catechol fragments. Thiolated aptamers against OTA were covalently attached to silver nanoparticles via AgÀS bonding. The interaction with OTA induced the conformational switch of the aptamer, which caused increase of the charge transfer resistance measured by EIS in the presence of ferricyanide ions. The LOD achieved (0.05 nM) was comparable to other electrochemical aptasensors employing sophisticated assembling technique and enzyme amplification of the signal. The aptasensor was validated in spiked beer samples. The recovery of the OTA determination was found to be 66.3 AE 14.1 % for light beer and 64.3 AE 1.8 % for dark beer.
De Gruyter eBooks, Mar 19, 2018
The development of electrochemical DNA sensors and aptasensors based on nanoparticles different i... more The development of electrochemical DNA sensors and aptasensors based on nanoparticles different in nature, size, shape, and preparation protocols has been considered with particular emphasis to the mechanism of their influence on signal readout and way of implementation in the biosensor assembly. Most attention is paid to application of Au nanoparticles and carbonaceous nanomaterials though the examples of other applications and hybrid nanomaterials are given. The analytical performance of DNA sensors and aptasensors utilizing nanomaterials is classified in accordance with their targets and role of nanoparticles in sensitivity and selectivity of the response. The trends of future progress in the biochemical applications of nanomaterials are discussed.
Pure and Applied Chemistry, Sep 26, 2017
DNA and aptasensors are widely used for fast and reliable detection of disease biomarkers, pharma... more DNA and aptasensors are widely used for fast and reliable detection of disease biomarkers, pharmaceuticals, toxins, metabolites and other species necessary for biomedical diagnostics. In the overview, the concept of spatially distributed redox mediators is considered with particular emphasis to the signal generation and biospecific layer assembling. The application of non-conductive polymers bearing redox labels, supramolecular carriers with attached DNA aptamers and redox active dyes and E-sensor concept are considered as examples of the approach announced.
Biosensors, May 12, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Talanta, Mar 1, 2019
Reversible inhibitors of acetylcholinesterase are increasingly applied in the Alzheimer's disease... more Reversible inhibitors of acetylcholinesterase are increasingly applied in the Alzheimer's disease therapy. Their determination with biosensors requires special attention to the enzyme immobilization due to importance of electrostatic and steric factors affecting accessibility of the active site to the substrate and inhibitor present simultaneously. In this work, polyelectrolyte complexes have been assembled from electrochemically inactive components with implementation of acetylcholinesterase from electric eel. The influence of the complex components and enzyme position on the assembling efficiency was explored using surface plasmon resonance and kinetic parameters of the enzyme with amperometry with Co phtalocyanine mediator. The biosensor developed showed robust response toward donepezil and berberine with limit of detection of 0.46 and 70 nM, respectively, within 1 minute after inhibitor addition. The sensitivity of determination coincides or is better than characteristics of biosensors based on covalently attached AChE described in the literature. The biosensor was tested on the example of drug determination in spiked samples of artificial urine (recovery 103% for 0.6 nM donepezil and 110% for 0.1 μM berberine).
Electroanalysis, Feb 12, 2016
Electrochemical sensor has been proposed on the base of glassy carbon electrode (GCE) modified wi... more Electrochemical sensor has been proposed on the base of glassy carbon electrode (GCE) modified with carbon black (CB) and pillar[5]arene (P[5]A). The characteristics of the peak currents were found to be sensitive to the incubation of the sensor in organic acid and DNA solution. The detection of n×(10−8–10−5) M of organic acid and down to (1–5)×10−18 g of DNA was attributed to the effect of the analytes on the aggregation and relative stability of oxidized and reduced forms of P[5]A. No signal interference with the alkali and alkali‐earth metal ions was found. The electrochemical sensor was tested in the detection of specific DNA interactions, i.e. reactive oxygen species damage and intercalating pharmaceuticals detection.
Journal of Nanoscience and Nanotechnology, Sep 1, 2014
Polyelectrolyte complexes based on electropolymerized phenothiazine dyes (Methylene Blue and Meth... more Polyelectrolyte complexes based on electropolymerized phenothiazine dyes (Methylene Blue and Methylene Green), poly(allylamine hydrochloride), polystyrene sulfonate and native DNA from salmon sperm have been for the first time obtained by self-assembling on the glassy carbon electrode using the layer-by-layer assembly and characterized using direct current voltammetry and electrochemical impedance spectroscopy. The changes in the charge transfer resistance and capacitance are attributed to the charge separation and the regularity of the layers depending on the number of layers and the position of DNA within the complex. Fenton reagent increases the resistance of the outer interface of the modifier with the maximal effect for the coatings including polymeric form of Methylene Green based coatings and direct contact of the DNA and polyphenothiazines. Meanwhile the selectivity of the response was found higher for the coatings based on poly(Methylene Blue). The difference in the behavior of the polyelectrolyte complex including different components makes it possible to distinguish the response related to the DNA damage and changes in the redox status of polyphenothiazines.
Sensors and Actuators B-chemical, Mar 1, 2016
Abstract Novel electrochemical aptasensor toward cytochrome c (Cyt c ) has been developed on the ... more Abstract Novel electrochemical aptasensor toward cytochrome c (Cyt c ) has been developed on the base of glassy carbon electrode (GCE) modified with electropolymerized neutral red (Poly-NR) and decacarboxylated pillar[5]arene (P[5]A-COOH) bearing terminal neutral red (NR) and aminated aptamer specific to Cyt c . Addition of Cyt c resulted in decrease of the cathodic peak current of NR on cyclic voltammogram due to suppression of the electron exchange between reduced and oxidized NR forms in the surface layer. The implementation of Cyt c in the surface layer was confirmed by scanning electron microscopy (SEM), atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS). Depending on the content of the surface layer and assembling protocol, the limits of detection (LODs) varied from 0.02 to 1.0 nM and linear range of concentrations was within three orders of magnitude. Interfering influence of some proteins and polyethylene glycol was characterized. The aptasensors developed can find application in detection of Cyt c as apoptosis agent in blood serum. This has been partially validated in model blood serum mimicking the ionic composition of the plasma.
Biosensors, Apr 30, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Series in sensors, Sep 25, 2013
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Papers by Gennady Evtugyn