Статті в журналах: "Glucose oxidase/glucose reaction"

1

Nováková, A., L. Schreiberová, and I. Schreiber. "Study of dynamics of glucose-glucose oxidase-ferricyanide reaction." Russian Journal of Physical Chemistry A 85, no. 13 (December 2011): 2305–9. http://dx.doi.org/10.1134/s003602441113019x.

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2

Číp, M., L. Schreiberová, and I. Schreiber. "Dynamics of the reaction glucose-catalase-glucose oxidase-hydrogen peroxide." Russian Journal of Physical Chemistry A 85, no. 13 (December 2011): 2322–26. http://dx.doi.org/10.1134/s0036024411130061.

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3

Murthy, A. Surya N., and Anita. "Benzoquinone-mediated glucose/glucose oxidase reaction at pyrolytic graphite electrode." Electroanalysis 5, no. 3 (April 1993): 265–68. http://dx.doi.org/10.1002/elan.1140050313.

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4

Johnson, Kristin A., Beth A. Kroa, and Tony Yourey. "Factors affecting reaction kinetics of glucose oxidase." Journal of Chemical Education 79, no. 1 (January 2002): 74. http://dx.doi.org/10.1021/ed079p74.

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5

Zeng, Ke, Minghui Yang, You-Nian Liu, and Avraham Rasooly. "Dual function hollow structured mesoporous Prussian blue mesocrystals for glucose biosensors." Analytical Methods 10, no. 32 (2018): 3951–57. http://dx.doi.org/10.1039/c8ay01456f.

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Dual function hollow structured mesoporous Prussian blue mesocrystals (HMPB) serve both as a scaffold carrier matrix to load the enzyme glucose oxidase and as a redox mediator of H₂O₂, the by-product of glucose oxidase catalyzed glucose reaction. The red and blue symbols represent glucose oxidase and HMPB, respectively.

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6

Hiraishi, H., A. Terano, S. Ota, H. Mutoh, M. Razandi, T. Sugimoto, and K. J. Ivey. "Role for iron in reactive oxygen species-mediated cytotoxicity to cultured rat gastric mucosal cells." American Journal of Physiology-Gastrointestinal and Liver Physiology 260, no. 4 (April 1, 1991): G556—G563. http://dx.doi.org/10.1152/ajpgi.1991.260.4.g556.

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The gastric epithelium is exposed to oxygen species that are generated within the lumen. Reactive oxygen species, enzymatically generated, cause injury to cultured rat gastric mucosal cells. Much interest has been focused on the role of iron in producing oxidant-mediated injury to the gastric mucosa, because iron is a catalyst that promotes the production of .OH possibly from O2-. and H2O2 (Haber-Weiss reaction) or from H2O2 alone (Fenton reaction). With the use of an iron chelator and an iron binding protein, we examined the role of iron in producing oxidant-mediated injury to cultured gastric mucosal cells. Reactive oxygen species and H2O2 were generated by hypoxanthine-xanthine oxidase and glucose-glucose oxidase, respectively, in buffer without iron. Pretreatment with deferoxamine diminished hypoxanthine-xanthine oxidase-induced 51Cr release from prelabeled cells, dose dependently. Furthermore, addition of deferoxamine to the reactive oxygen species-generating system also protected against the injury. However, apotransferrin (which binds extracellular iron) failed to protect cells. Pretreatment with .OH scavengers was partially protective. Depletion of glutathione with diethyl maleate enhanced reactive oxygen species-mediated cytolysis; such cytolysis was inhibited by deferoxamine. Deferoxamine also decreased 51Cr release induced by glucose-glucose oxidase. We conclude that intracellular iron plays a crucial role in mediating oxygen radical damage to gastric mucosal cells. The .OH, produced from H2O2 by the iron-catalyzed Fenton reaction, seems to be the main mediator of oxidant-induced cytotoxicity to gastric mucosal cells in vitro.

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7

Michael, John R., Boaz A. Markewitz, and Donald E. Kohan. "Oxidant stress regulates basal endothelin-1 production by cultured rat pulmonary endothelial cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 273, no. 4 (October 1, 1997): L768—L774. http://dx.doi.org/10.1152/ajplung.1997.273.4.l768.

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Endothelin-1 (ET-1) is a pluripotent mediator that modulates vascular tone and influences the inflammatory response. Patients with inflammatory lung disorders frequently have elevated circulating ET-1 levels. Because these pathophysiological conditions generate reactive oxygen species that can regulate gene expression, we investigated whether the level of oxidant stress influences ET-1 production in cultured rat pulmonary arterial endothelial cells (RPAEC). Treatment with the antioxidant 1,3-dimethyl-2-thiourea (10 mM) or the iron chelator deferoxamine (1.8 μM) doubles basal ET-1 release. Conversely, exposing cells to H2O2generated by glucose and glucose oxidase (0.1–10 mU/ml) for 4 h causes a concentration-dependent decrease in ET-1 release. This effect occurs at concentrations of glucose oxidase that do not affect [3H]leucine incorporation or specific 51Cr release from RPAEC. Catalase prevents the decrease in ET-1 synthesis caused by glucose and glucose oxidase. Glucose and glucose oxidase decrease not only ET-1 generation but also ET-1 mRNA as assessed by semiquantitative polymerase chain reaction. Our results indicate that changes in oxidative stress can either up- or downregulate basal ET-1 generation by cultured pulmonary endothelial cells.

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8

Yee, Ying Chuin, Rokiah Hashim, Ahmad Ramli Mohd Yahya, and Yazmin Bustami. "Colorimetric Analysis of Glucose Oxidase-Magnetic Cellulose Nanocrystals (CNCs) for Glucose Detection." Sensors 19, no. 11 (May 31, 2019): 2511. http://dx.doi.org/10.3390/s19112511.

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Glucose oxidase (EC 1.1.3.4) sensors that have been developed and widely used for glucose monitoring have generally relied on electrochemical principle. In this study, the potential use of colorimetric method for glucose detection utilizing glucose oxidase-magnetic cellulose nanocrystals (CNCs) is explored. Magnetic cellulose nanocrystals (magnetic CNCs) were fabricated using iron oxide nanoparticles (IONPs) and cellulose nanocrystals (CNCs) via electrostatic self-assembly technique. Glucose oxidase was successfully immobilized on magnetic CNCs using carbodiimide-coupling reaction. About 33% of GOx was successfully attached on magnetic CNCs, and the affinity of GOx-magnetic CNCs to glucose molecules was slightly higher than free enzymes. Furthermore, immobilization does not affect the specificity of GOx-magnetic CNCs towards glucose and can detect glucose from 0.25 mM to 2.5 mM. Apart from that, GOx-magnetic CNCs stored at 4 °C for 4 weeks retained 70% of its initial activity and can be recycled for at least ten consecutive cycles.

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9

Wang, Hong, Yang Yang Liu, Xiao Jing Yao, Yan Li, Ji Yu Wu, and Jian Guo Cui. "Research on Glucose Oxidase Biosensor Based on Reverse Iontophoresis." Advanced Materials Research 641-642 (January 2013): 785–88. http://dx.doi.org/10.4028/www.scientific.net/amr.641-642.785.

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Objective: Making a glucose sensor to detect the glucose which is extracted from the tissue fluid on reverse iontophoresis. Method: In the role of the catalysis of glucose oxidase which was fixed in polyethylene oxide gel, the glucose and potassium ferricyanide were change into gluconic acid and potassium ferrocyanide. Then we could get the concentration of glucose by detecting the current which was created by the redox reaction. Results: The glucose sensors could detect the concentration of glucose in the range of 2.2~22mmol/l and have a good linear too. The conformance test results show that the deviation of multiple measurements of the same sensor is less than 2% and the reaction time is less than 1s. Conclusion: The sensors could detect the blood glucose.

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10

Zou, Quan, Gong Cheng, and Yu Zhang. "Study on electrochemical biosensor based on screen-printed electrode." Modern Physics Letters B 32, no. 34n36 (December 30, 2018): 1840061. http://dx.doi.org/10.1142/s0217984918400614.

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It is known that redox reaction can take place among the solutions of potassium ferrocyanide (K4[Fe(CN)6]), glucose (C6H[Formula: see text]O6) and glucose oxidase (Glucose Oxidase, GOD). In this work, the method of electrochemical biosensor detection based on screen printed electrode was used to observe the redox reaction among these solutions. The relationship between redox reaction and parameters was studied by examining the effects of concentration and scanning speed of three solutions.

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11

Leskovac, Vladimir, Jasmina Svirčević, and Mirjana Radulović. "The oxidative part of the glucose-oxidase reaction." International Journal of Biochemistry 21, no. 10 (January 1989): 1083–88. http://dx.doi.org/10.1016/0020-711x(89)90047-5.

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12

Wang, Chen, Zhen-Huan Sheng, Jun Ouyang, Jing-Juan Xu, Hong-Yuan Chen, and Xing-Hua Xia. "Nanoconfinement Effects: Glucose Oxidase Reaction Kinetics in Nanofluidics." ChemPhysChem 13, no. 3 (February 2012): 762–68. http://dx.doi.org/10.1002/cphc.201100842.

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13

Cho, Myung D., and Yoshiyuki Okamoto. "Enzymatical chain scission of water soluble polymers by the glucose-glucose oxidase reaction." Macromolecular Rapid Communications 15, no. 8 (August 1994): 629–31. http://dx.doi.org/10.1002/marc.1994.030150802.

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14

DONG, Shaojun. "(Keynote, Digital Presentation) Why Au Nanoparticles Could Behave As a Glucose Oxidase Mimic." ECS Meeting Abstracts MA2022-01, no. 53 (July 7, 2022): 2194. http://dx.doi.org/10.1149/ma2022-01532194mtgabs.

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The Au nanoparticle has been found to be the excellent glucose oxidase mimic, while the catalytic process has rarely been studied. Here, we revealed that the process of glucose oxidation catalyzed by Au nanoparticles is the same as that of natural glucose oxidase, namely, a two-step reaction including the dehydrogenation of glucose and the subsequent reduction of O2 to H2O2 by two electrons. Pt, Pd, Ru, Rh, and Ir nanoparticles can also catalyze the dehydrogenation of glucose, except that O2 is preferably reduced to H2O. Using the electron transfer property of noble metal nanoparticles, we overcame the limitation that H2O2 must be produced in the traditional two-step glucose assay and realized the rapid colorimetric detection of glucose. Noble metal nanoparticles have also been found to mimic various enzymatic electron transfer reactions including cytochrome c, coenzymes as well as nitrobenzene reductions.

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15

Chang, J., N. V. Rao, B. A. Markewitz, J. R. Hoidal, and J. R. Michael. "Nitric oxide donor prevents hydrogen peroxide-mediated endothelial cell injury." American Journal of Physiology-Lung Cellular and Molecular Physiology 270, no. 6 (June 1, 1996): L931—L940. http://dx.doi.org/10.1152/ajplung.1996.270.6.l931.

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Because nitric oxide is being used to treat acute lung injury and because it may either reduce or potentiate oxidant-mediated vascular injury, we studied the effect of the nitric oxide donor S-nitroso-N-acetyl-D-penicillamine (SNAP) on hydrogen peroxide (H2O2)-induced injury to cultured rat lung microvascular endothelial cells (RLMVC). Cells were exposed to H2O2 through its enzymatic generation by glucose and glucose oxidase or by its direct application. Glucose oxidase exposure causes a concentration- and time-dependent increase in 51chromium (51Cr) release from RLMVC. Catalase, dimethylthiourea or deferoxamine protects against this oxidant injury. SNAP (100 microM) prevents the increase in 51Cr release resulting from glucose oxidase or direct application of H2O2. N-acetyl-D-penicillamine is ineffective. Photo-decayed SNAP slightly decreases the 51Cr release caused by glucose oxidase but not the injury produced by directly adding H2O2. Treatment with the guanosine 3',5'-cyclic monophosphate (cGMP) analogue 8-BrcGMP (1-10 mM) provides no protection. SNAP decreases in vitro the net oxidation of ferrous to fcrric iron by H2O2, the iron-catalyzed consumption of H2O2 in Fenton's reaction, the iron-mediated generation of hydroxyl radicals, and the Fe(2+)-H2O2-catalyzed peroxidation of lipid membranes. Providing exogenous nitric oxide dramatically prevents H2O2-mediated endothelial injury, likely by reducing iron-mediated oxidant generation and subsequent lipid peroxidation.

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16

Fischer, Y., J. Thomas, J. Kamp, E. Jüngling, H. Rose, C. Carpéné, and H. Kammermeier. "5-hydroxytryptamine stimulates glucose transport in cardiomyocytes via a monoamine oxidase-dependent reaction." Biochemical Journal 311, no. 2 (October 15, 1995): 575–83. http://dx.doi.org/10.1042/bj3110575.

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This study deals with the effect of 5-hydroxytryptamine (5-HT; serotonin) on glucose transport in isolated rat cardiac myocytes. In these cells, 5-HT (10-300 microns), as well as tryptamine, 5-methoxytryptamine and dopamine, elicited a 3-5 fold increase in glucose transport, as compared with control. This effect was maximal after 90 min, and was concomitant with a 1.8- and 1.5-fold increase in the amounts of glucose transporters GLUT1 and GLUT4 at the cell surface of the cardiomyocytes, as determined by using the photoaffinity label 3H-2-N-[4-(1-azi-2,2,2-trifluoroethyl)benzoyl]-1,3-bis-(D-manno s-4-yl) propyl-2-amine (3H-ATB-BMPA). In contrast, 3-3000 microM of the selective 5-HT receptor agonists 5-carboxyamido-tryptamine, alpha-methyl-serotonin, 2-methyl-serotonin or renzapride failed to stimulate glucose transport. The effect of 5-HT was not affected by (i) the 5-HT receptor antagonists methysergide (1 microM), ketanserin (1 microM), cyproheptadine (1 microM), MDL 72222 (1 microM) or ICS 205-930 (3 microM), nor by (ii) the adrenergic receptor antagonists prazosin (1 microM), yohimbine (1 microM) or propranolol (5 microM), nor by (iii) the dopaminergic antagonists SCH 23390 (1 microM) or haloperidol (1 microM). The monoamine oxidase inhibitors clorgyline (1 microM) and tranylcypromine (1 microM) completely suppressed the effect of 5-HT, whereas the control and insulin-stimulated rates of glucose transport were unaffected. Addition of catalase or glutathione diminished the 5-HT-dependent stimulation of glucose transport by 50%; these two factors are known to favour the degradation of H2O2 (which can be formed during the deamination of amines by monoamine oxidases). Glutathione also depressed the stimulatory action of exogenously added H2O2 (20 microM) by 30%. Furthermore, in cells treated with 5_HT, a time-dependent accumulation of 5-hydroxy-1H-indol-3-ylacetic acid (a product of 5-HT metabolism via monoamine oxidases) was observed, which paralleled the changes in glucose transport. In conclusion, the stimulation of glucose transport by 5-HT in cardiomyocytes is not mediated by a 5-HT1, 5-HT2, 5-HT3 or 5-HT4 receptor, nor by an adrenergic or dopaminergic receptor, but is likely to occur through the degradation of by a monoamine oxidase and concomitant formation of H2O2.

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17

Anuar, N. F. S., Halina Misran, Abreeza Manap, and S. Z. Othman. "Review on Immobilization of Nanoparticles for Fabrication of Glucose Biosensor." Applied Mechanics and Materials 773-774 (July 2015): 720–24. http://dx.doi.org/10.4028/www.scientific.net/amm.773-774.720.

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Glucose biosensor has been improvised from time to time in order to provide fast and accurate detection of glucose concentration especially for diabetic patients. Recently, nanoparticles have rising attention engaging with biosensor application. Nanoparticles serve as the carrier of enzyme immobilization whereas; enzyme is a biological catalyst that reacts with specific substrate in metabolic reaction. Glucose oxidase (GOx) in particular, is the most common enzyme used for fabrication of biosensor. Glucose measurement was done by using amperometric measurement that converted corresponding biochemical reaction between glucose and GOx into electrical output. Response behavior studies were conducted in order to compare the successfulness of GOx immobilization onto GOx-biosensor. Immobilization of glucose oxidase onto nanoparticles can lead towards tremendous impacts especially in new, high sensitivity biosensor.

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18

Mladenoska, Irina, Verica Petkova, and Tatjana Kadifkova Panovska. "Pre-fermentative treatment of a model wine with aim to serve as a functional food with decreased alcohol content." Macedonian Pharmaceutical Bulletin 63, no. 01 (2017): 47–53. http://dx.doi.org/10.33320/maced.pharm.bull.2017.63.01.005.

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The effect of substrate concentration on the enzyme activity in the reaction of glucose conversion into gluconic acid was investigated by using three different enzyme preparations in media with two different glucose concentrations. The media were simulating the conditions in the must, thus named as minimal model must, and were composed form combination of several organic acids and glucose. Those media were having initial pH of 3.5 that is a very unfavorable for glucose oxidase activity having a pH optimum at the pH value of 5.5. Among the three preparations used, the bakery additive, Alphamalt Gloxy 5080, was the most active in the medium with glucose concentration of 10 g/L, showing conversion of more than 70% for the period of 24 h, while the same enzyme preparation in the medium with 100 g/L glucose converted only about 7% of glucose. The pH value of the medium at the beginning and at the end of the enzymatic reaction was a good indicator of the enzyme activity. It seems that for the conversion of glucose in higher concentration, enzymatic preparation in high concentration should also be used. The preliminary attempt of immobilization of two preparations of glucose oxidases in alginate beads was also performed and a successful immobilization procedure for utilization in food industry was preliminarily developed. Keywords: glucose oxidases, enzymatic pretreatment, glucose, gluconic acid, model wine, functional food

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19

Тихонов, Борис Борисович, Полина Юрьевна Стадольникова, Александр Иванович Сидоров, and Михаил Геннадьевич Сульман. "DETERMINATION OF GLUCOSE OXIDASE ACTIVITY BY SPECTROPHOTOMETRIC METHOD." Вестник Тверского государственного университета. Серия: Химия, no. 2(44) (June 25, 2021): 18–25. http://dx.doi.org/10.26456/vtchem2021.2.2.

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В статье рассматривается универсальная, чувствительная, быстрая и воспроизводимая методика определения активности глюкозооксидазы, основанная на окислении пероксидом водорода йодида калия в присутствии молибдата аммония и фотометрировании образующегося синего комплекса «йод-крахмал». Построен калибровочный график для определения концентрации пероксида водорода в реакционной смеси. Проведен анализ образования пероксида водорода в реакции окисления глюкозы глюкозооксидазой при варьировании начальной концентрации глюкозы. The article developed a universal, sensitive, fast and reproducible method for determining glucose oxidase activity, based on the oxidation of potassium iodide by hydrogen peroxide in the presence of ammonium molybdate and photometry of the resulting blue iodine-starch complex. A calibration graph is constructed to determine the concentration of hydrogen peroxide in the reaction mixture. Analysis of hydrogen peroxide formation in glucose oxidation reaction with glucose oxidase at variation of initial glucose concentration was performed.

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20

Schmidt, Peter M., R. Stephen Brown, and John H. T. Luong. "Inclusion complexation of tetrathiafulvalene in cyclodextrins and bioelectroanalysis of the glucose-glucose oxidase reaction." Chemical Engineering Science 50, no. 12 (June 1995): 1867–76. http://dx.doi.org/10.1016/0009-2509(95)00046-8.

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21

Kwon, Jung-Yeon, Mashooq Khan, and Soo-Young Park. "pH-Responsive liquid crystal double emulsion droplets prepared using microfluidics." RSC Advances 6, no. 61 (2016): 55976–83. http://dx.doi.org/10.1039/c6ra03951k.

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22

Shen, Bowen, Molan Qing, Liying Zhu, Yuxian Wang, and Ling Jiang. "Dual-Enzyme Cascade Composed of Chitosan Coated FeS2 Nanozyme and Glucose Oxidase for Sensitive Glucose Detection." Molecules 28, no. 3 (January 31, 2023): 1357. http://dx.doi.org/10.3390/molecules28031357.

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Immobilizing enzymes with nanozymes to catalyze cascade reactions overcomes many of the shortcomings of biological enzymes in industrial manufacturing. In the study, glucose oxidases were covalently bound to FeS2 nanozymes as immobilization carriers while chitosan encapsulation increased the activity and stability of the immobilized enzymes. The immobilized enzymes exhibited a 10% greater increase in catalytic efficiency than the free enzymes while also being more stable and catalytically active in environments with an alkaline pH of 9.0 and a high temperature of 100 °C. Additionally, the FeS2 nanozyme-driven double-enzyme cascade reaction showed high glucose selectivity, even in the presence of lactose, dopamine, and uric acid, with a limit of detection (LOD) (S/N = 3) as low as 1.9 × 10−6 M. This research demonstrates that nanozymes may be employed as ideal carriers for biological enzymes and that the nanozymes can catalyze cascade reactions together with natural enzymes, offering new insights into interactions between natural and synthetic biosystems.

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23

Smalley, D. L., and M. E. Bradley. "New test for urinary glucose (BM33071) evaluated." Clinical Chemistry 31, no. 1 (January 1, 1985): 90–92. http://dx.doi.org/10.1093/clinchem/31.1.90.

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Abstract Results for urinary glucose by the Boehringer Mannheim BM33071 test pad and a hexokinase-based method agree well. The new test, which involves the glucose oxidase/peroxidase reaction, measures as little as 260 mg of glucose per liter. Acetoacetate, beta-hydroxybutyrate, and human hemoglobin do not interfere.

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24

Siyal, Lovnish, Benu Kumar, Arpita Bhattacharya, and Rachana Sahney. "Entrapment of Glucose Oxidase in Reverse Micelle Microemulsion Systems for Glucose Detection in Lipid Based Food Products." Asian Journal of Chemistry 31, no. 11 (September 28, 2019): 2635–41. http://dx.doi.org/10.14233/ajchem.2019.22260.

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Entrapment of glucose oxidase (GOx) enzyme in a new reverse micelle emulsion system was studied. The microemulsion consists of aqueous phase (buffered enzyme)/SPAN 85/n-decane. Critical micelle concentration (CMC) of surfactant-SPAN 85 in n-decane was determined using dynamic light scattering study and it was used to develop microemulsion system. Most stable and optically transparent microemulsion with entrapped glucose oxidase showed higher values of specific enzyme activity, maximum reaction rate (Vmax) and turn over number and low value of Michaelis-constant (Km) in comparison to homogeneous GOx (enzyme-glucose oxidase) system. The microemulsion system was successfully used to quantify D-glucose in lipid based food products without any sample preparation. Comparison of these results with chemical method (phenol-sulfuric acid method) and commercial kit method used in food industry validate the efficiency of the new proposed system. The study provides new information about the glucose content of some commonly consumed milk based products where nutritional labels do not accurately show true glucose content. These findings provide support for comprehensive glucose labeling to food products commonly used by the children.

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25

MATSU-URA, Shinya, Yuji YAMAUCHI, Hidenobu OHMORI, and Hatsuo MAEDA. "Blood glucose determination with an acetyl resorufin-glucose oxidase system as a fluorometric indicator reaction." BUNSEKI KAGAKU 50, no. 7 (2001): 475–79. http://dx.doi.org/10.2116/bunsekikagaku.50.475.

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26

Baker, Warren L. "GLUCOSE OXIDASE REACTION FOR ESTIMATION OF GLUCOSE WITHOUT HORSERADISH PEROXIDASE. SOME MICROBIOLOGICAL AND FERMENTATION APPLICATIONS." Journal of the Institute of Brewing 97, no. 6 (November 12, 1991): 457–62. http://dx.doi.org/10.1002/j.2050-0416.1991.tb01086.x.

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27

Chrisnasari, Ruth, Zerlina Gabriela Wuisan, Arief Budhyantoro, and Restu Kartiko Widi. "Glucose Oxidase Immobilization on TMAH-Modified Bentonite." Indonesian Journal of Chemistry 15, no. 1 (March 30, 2015): 22–28. http://dx.doi.org/10.22146/ijc.21219.

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The influence of bentonite modification by tetramethyl ammonium hydroxide (TMAH) on its capability to immobilize glucose oxidase (GOX) was studied. Modification of bentonite was conducted by the adding of 0-5% (v/v) TMAH. The observed results show that the different concentrations of TMAH affect the percentage of immobilized enzyme. The results of this study show that the best concentration of TMAH is 5% (v/v) which can immobilize up to 84.71% of GOX. X-ray diffraction (XRD) and Fourier Transforms Infrared Spectroscopy (FTIR) studies have been carried out to observe the structural changes in bentonite due to TMAH modification. The obtained immobilized GOX show the optimum catalytic activity on reaction temperature of 40-50 °C and pH of 7. The immobilized GOX kinetics at the optimum conditions determined the Km and Vmax value to be 4.96x10-2 mM and 4.99x10-3 mM.min-1 respectively. In addition, the immobilized GOX on TMAH-modified bentonite is stable enough so it could be re-used six times before its activity decreased by 39.44%.

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28

Kim, Kun-Yong, Ho Chang, Win-Der Lee, Yi-Fan Cai, and You-Jia Chen. "The Influence of Blood Glucose Meter Resistance Variation on the Performance of a Biosensor with a Gold-Coated Circuit Board." Journal of Sensors 2019 (February 11, 2019): 1–8. http://dx.doi.org/10.1155/2019/5948182.

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In this study, a novel gold-coated test strip for blood glucose measurement has been designed. Such gold-coated test strip is feasible for mass production to achieve economies of scale. Cyclic voltammetry was applied to test strips to undergo electrochemical reaction under a potential range of ±0.4 V. Glucose oxidase (GOD) was added into K3[Fe(CN)6]. When glucose oxidase undergoes electrochemical reaction, the medium, K3[Fe(CN)6], will act as an electron acceptor, causing the electrodes on the test strip to generate a pair of clear anodic and reductive peaks. The maximum of the anodic and reductive peaks can be used as reference to adjust the resistance of the blood glucose meter. The experimental results show that by adjusting the resistance of the blood glucose meter, the accuracy of blood glucose meter reading can be tuned and blood glucose reading can be stabilized. Therefore, when the resistance of the blood glucose meter is at 2.4 KΩ, the standard deviation (STD) and coefficient of variation (CV) of the test strip are lower than those of the test strips measured at resistances of 2.2 KΩ and 2.6 KΩ. It has been proved in this study that adjusting the resistance of the blood glucose meter can optimize the chemical reaction on gold-coated test strips as well as its reading. This method can also be applied to tune the accuracy of readings for test strips coated with other materials.

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29

UEMATSU, Kohei, Akihito SHINOZAKI, and Hajime KATANO. "Determination of Polyhexamethylene Biguanide Utilizing a Glucose Oxidase Enzymatic Reaction." Analytical Sciences 35, no. 9 (September 10, 2019): 1021–25. http://dx.doi.org/10.2116/analsci.19p095.

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30

Zook, Christine M., and William R. LaCourse. "Pulsed Amperometric Detection of Microdialysates from the Glucose Oxidase Reaction." Analytical Chemistry 70, no. 4 (February 1998): 801–6. http://dx.doi.org/10.1021/ac971106o.

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31

Jug, Karl, and Heiko Gerwens. "QCMEE study of the reductive half-reaction of glucose oxidase." International Journal of Quantum Chemistry 77, no. 1 (2000): 71–81. http://dx.doi.org/10.1002/(sici)1097-461x(2000)77:1<71::aid-qua8>3.0.co;2-a.

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32

German, Natalija, Almira Ramanaviciene, and Arunas Ramanavicius. "Formation of Polyaniline and Polypyrrole Nanocomposites with Embedded Glucose Oxidase and Gold Nanoparticles." Polymers 11, no. 2 (February 20, 2019): 377. http://dx.doi.org/10.3390/polym11020377.

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Анотація:

Several types of polyaniline (PANI) and polypyrrole (Ppy) nanocomposites with embedded glucose oxidase (GOx) and gold nanoparticles (AuNPs) were formed by enzymatic polymerization of corresponding monomers (aniline and pyrrole) in the presence of 6 and 13 nm diameter colloidal gold nanoparticles (AuNPs(6nm) or AuNPs(13nm), respectively) or chloroaurate ions (AuCl4−). Glucose oxidase in the presence of glucose generated H2O2, which acted as initiator of polymerization reaction. The influence of polymerization bulk composition and pH on the formation of PANI- and Ppy-based nanocomposites was investigated spectrophotometrically. The highest formation rate of PANI- and Ppy-based nanocomposites with embedded glucose oxidase and gold nanoparticles (PANI/AuNPs-GOx and Ppy/AuNPs-GOx, respectively) was observed in the solution of sodium acetate buffer, pH 6.0. It was determined that the presence of AuNPs or AuCl4− ions facilitate enzymatic polymerization of aniline and pyrrole.

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33

Xia, Fang Quan, and Wen Rui Jin. "Measurement of Glucose Concentration in Cancer Cell by Catalyzed-Enzyme Reaction." Advanced Materials Research 306-307 (August 2011): 20–24. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.20.

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In this work, glucose concentration in gastric cancer cell was determinaed based on a coupled enzyme catalyzed reaction. glucose oxidase (GOD) reacted with glucose to form gluconic acid and H2O2. In the presence of horseradish peroxidase (HRP), the H2O2 then reacted with 10-acetyl-3,7- dihydroxyphenoxazine (ADHP) in a 1:1 stoichiometry to generated the fluorescent products, resorufin. So that, the glucose concentration assay could be performed by fluorometric analysis resorufin. Glucose solution or Gastric cancer cells lysate were catalyzed and detected by epi-fluorescence microscopy in a quartz capillary fluorometer cell. The fluorescence intensity were analysis by the MetaMorph Software. The linear relationship of the glucose concentrations covered a range of 1.00×10-8-1.00×10-5 mol/L with a correlation coefficient of 0.9994. LOD was 5.30×10-9 mol/L(cL = ksB/b). The glucose concentration in cancer cells lysate was 8.03×10-6 mol/L (n =4).

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34

Saito, Koshi. "Potential Competency of Glucose Oxidase for Modification of Flower Colour in Carthamus tinctorius." Zeitschrift für Naturforschung C 47, no. 3-4 (April 1, 1992): 205–8. http://dx.doi.org/10.1515/znc-1992-3-407.

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Abstract Glucose was found to be a potential stimulator of carthamin formation in triturated florets of C. tinctorius. At a 10 mM glucose level, carthamin-producing activity was raised from 3.2- fold (upper) to 2.0-fold (lower) level compared with the control having no sugar. Glucose oxidase (β-D-glucose: oxygen 1-oxidoreductase, EC 1.1.3.4) from Aspergillus niger could catalyze the conversion of precarthamin to carthamin, indicative of flower colour modification in C. tinctorius. For optimum reaction, precarthamin, β-D-glucose, and oxygen were required. No manganese enhanced the catalytic enzyme process.

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35

Bhatt, M. P., N. Rai, S. Pokhrel, P. Acharya, S. B. Marhatta, D. P. Khanal, A. Nagila, and P. D. Chataut. "Standardization of Visible Kinetic Assay for the Estimation of Plasma Glucose by Glucose Oxidase and Peroxidase Method." Journal of Manmohan Memorial Institute of Health Sciences 7, no. 1 (December 1, 2021): 49–59. http://dx.doi.org/10.3126/jmmihs.v7i1.43150.

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Objective: In the clinical laboratory, glucose is the most frequently analyzed test in blood which plays a vital role in the diagnosis and management of patients suffering from diabetes mellitus and metabolic disorders. The glucose oxidase and peroxidase (GOD-POD) method is an end point reaction method for glucose estimation, which is cheap and readily available in routine laboratories with significant time consumption. However, Glucose estimation by hexokinase is available for rapid estimation that may cost comparatively higher for the routine laboratories. Thus, our study is designed to standardize rapid and convenient method of plasma glucose estimation with modification by kinetic mode based on GOD-POD reaction for the rapid and high through put analysis of glucose estimation using semi-automated or autoanalyzers. Method: Photometric linearity of the kinetic method is compared with that of end point reaction methods. Furthermore, correlation between an endpoint and kinetic method was determined using Pearson correlation using plasma from normal and diabetic patients (n=32) visiting Manmohan Memorial Teaching Hospital, Kathmandu. Result: Our study showed, significant positive correlation between the end point and the kinetic method (r=0.99) The linearity of modified kinetic (GOD-POD) method is up to 400 mg/dl in comparison to that of existing end point method (500 mg/dl), which covers the normoglycemic to pathological hyperglycemic range of glucose estimation in routine laboratories. Conclusion: The significant positive correlation of our visible kinetic method with end point reaction method shows possibilities for the high through put and rapid analysis of the glucose estimation in 3 minute using semi-automated and autoanalizers.

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36

Hsu, Cheng-Chih, Wan-Yu Chung, Chun-Yi Chang, Chyan-Chyi Wu, and Cheng-Ling Lee. "Enzymatic Glucose Fiber Sensor for Glucose Concentration Measurement with a Heterodyne Interferometry." Sensors 23, no. 6 (March 9, 2023): 2990. http://dx.doi.org/10.3390/s23062990.

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Анотація:

In this study, we developed a glucose fiber sensor incorporating heterodyne interferometry to measure the phase difference produced by the chemical reaction between glucose and glucose oxidase (GOx). Both theoretical and experimental results showed that the amount of phase variation is inversely proportional to glucose concentration. The proposed method provided a linear measurement range of the glucose concentration from 10 mg/dL to 550 mg/dL. The experimental results indicated that the sensitivity is proportional to the length of the enzymatic glucose sensor, and the optimum resolution can be obtained at a sensor length of 3 cm. The optimum resolution of the proposed method is better than 0.6 mg/dL. Moreover, the proposed sensor demonstrates good repeatability and reliability. The average relative standard deviation (RSD) is better than 10% and satisfied the minimum requirement for point-of-care devices.

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37

Vrbová, Eva, and Miroslav Marek. "Preparation of enzyme electrode for D-glucose determination by immobilization of glucose oxidase on collagen membrane." Collection of Czechoslovak Chemical Communications 55, no. 10 (1990): 2568–74. http://dx.doi.org/10.1135/cccc19902568.

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An enzyme electrode for the determination of D-glucose was prepared by immobilization of glucose oxidase (EC 1.1.3.4.) on an activated collagen membrane using glutaraldehyde and the Ugi reaction resp. and by subsequent fixation of the membrane to an oxygen sensor of the Clark type. Two different procedures for the modification of the support, the composition of the reaction mixture and the immobilization time were examined. The electrode prepared was tested as regards the effect of pH and temperature on the magnitude of the response. The range of the linear dependence of the sensor response on substrate concentration (1.7 . 10-5 - 2.0 . 10-3), the apparent Michaelis constant of the immobilized enzyme (KM(app.) = 4.16 . 10-3 mol dm-3) and the stability of the biosensor as function of storage mode and number of assays performed with one electrode were determined. In view of the high stability and linear range of the concentration dependence the enzyme electrode is suitable for the determination of D-glucose in samples analyzed in agricultural and food laboratories.

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38

Fatoni, Amin, Vonia Febriana Hidayah, Suyata Suyata, Hartiwi Diastuti, and Mekar Dwi Anggraeni. "Chitosan–Fe3O4 Nanoparticles Cryogel for Glucose Biosensor Development." Science and Technology Indonesia 8, no. 1 (January 19, 2023): 52–58. http://dx.doi.org/10.26554/sti.2023.8.1.52-58.

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Chitosan was widely used as a supporting material for enzyme immobilization. However, the non-conductive properties of chitosan could be a severe problem in the application of biosensors with electrochemical detection. This research aimed to modify the chitosan cryogel with Fe3O4 nanoparticles for glucose biosensor application. The glucose biosensor used glucose oxidase enzyme as biological sensing element which was immobilized on the working electrode of electrochemical detection. Chitosan-Fe3O4 composite cryogel was used as supporting material for glucose oxidase immobilization. The detection optimization was also performed by varying the operating conditions such as buffer pH and reaction temperature. The result showed the optimum conditions were the addition of Fe3O4 nanoparticles for 4% (w/v), phosphate buffer solution of 100 mM with pH of 7.0, and reaction temperature at 25°C. The glucose determination showed linearity for increasing oxidation peak and decreasing reduction peak with the glucose concentration, with regression equation of y = -6.804x – 104.32 and y = 4.5872x + 133.37 respectively. Furthermore, the limit of detection and limit of quantification for oxidation peaks were 0.38 mM and 1.25 mM respectively. The reduction peak showed a limit of detection of 0.32 mM and a limit of quantification of 1.07 mM.

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39

Гребенникова, Ольга Валентиновна. "HETEROGENEOUS BIOCATALYSTS BASED ON PEROXIDASE AND GLUCOSE OXIDASE." Вестник Тверского государственного университета. Серия: Химия, no. 2(48) (July 7, 2022): 16–22. http://dx.doi.org/10.26456/vtchem2022.2.2.

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В работе описывается способ получения биферментых систем на основе глюкозооксидазы и пероксидазы корня хрена. Выбранные ферменты были ковалентно иммобилизованы на магнитные наночастиц, синтезированные методом со-осаждения, и неорганический носитель SiO. Образцы носителей были предварительно модифицированы и активированы. Полученные биокатализаторы тестировались в каскадной реакции окисления D-глюкозы и 2,2'-азино-бис-(3-этилбензтиозолин-6сульфокислоты) диаммониевой соли. Подобраны оптимальные условия работы биферментынх систем (температура 45 С, рН 6.0). The paper describes a method for obtaining bienzymatic systems based on glucose oxidase and horseradish root peroxidase. The selected enzymes were covalently immobilized on magnetic nanoparticles synthesized by the coprecipitation method and an inorganic SiO support. The carrier samples were pre-modified and activated. The resulting biocatalysts were tested in a cascade oxidation reaction of D-glucose and 2,2'-azino-bis-(3ethylbenzthiozolin-6-sulfonic acid) diammonium salt. Optimum conditions for the operation of bienzymatic systems (temperature 45 C, pH 6.0) were selected.

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40

Dou, Xiaoming, and Yukihiro Ozaki. "Raman Study of Enzyme Reactions Using Potassium Ferricyanide as a Reaction Mediator: Quantitative Analysis of Substrates and Measurement of Enzyme Activity for Glucose Oxidase and Lactate Oxidase." Applied Spectroscopy 52, no. 6 (June 1998): 815–19. http://dx.doi.org/10.1366/0003702981944544.

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This paper describes a Raman study of enzyme reactions that use potassium ferricyanide as a reaction mediator. The enzyme reaction systems investigated consisted of glucose oxidase (GOD), glucose, and potassium ferricyanide, and of lactate oxidase (LOD), lactate, and potassium ferricyanide. Raman spectra were measured for the above enzyme systems every 2 s to monitor the progress of the enzyme reactions at real time. The observed Raman spectra showed only three peaks at 2186, 2095, and 2022 cm−1 due to C N stretching modes of potassium ferricyanide (2186 cm−1) and potassium ferrocyanide (2095 and 2022 cm−1); with the progress of the enzyme reactions, the band at 2186 cm−1 decreases while those at 2095 and 2022 cm−1 increase. From the differentiation of the Raman intensity at 2022 cm−1, we could calculate the velocity ( V′) of the intensity change that directly reflects the rate ( V) of the enzyme reactions. By plotting the velocity thus obtained ( V′) vs. the concentration of the enzyme substrate ([ S]), we were able to develop a calibration curve to predict the concentration of the enzyme substrate. For GOD, the correlation coefficient ( R) and the detection limit of this calibration curve were 0.99 and 20 mg/dL, respectively. This detection limit was better than that obtained from conventional glucose sensors. For LOD, we were able to determine Michaelis constant ( Km) from the maximum velocity ( Vmax). The method proposed here is applicable to various kinds of enzymes that use potassium ferricyanide as a reaction mediator.

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41

GULOTTA, Florencia A., Ladislao DIAZ VERGARA, Mariana MONTENEGRO, Nancy F. FERREYRA, and Verónica I. PAZ ZANINI. "SELF-ASSEMBLED MULTILAYERS OF WATER GLUCOSE MODIFIED-CHITOSAN AND GLUCOSE OXIDASE FOR DETECTION OF GLUCOSE IN MILK SAMPLES." SOUTHERN JOURNAL OF SCIENCES 30, no. 34 (December 20, 2022): 1–7. http://dx.doi.org/10.48141/sjs.v30.n34.2022.01_ferreyra_pgs_01_07.pdf.

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Background: A crucial aspect of electrochemical enzymatic biosensor development is the immobilization of the enzymes, as it directly influences the sensitivity of the bioelectrode. Among the different methods used to incorporate enzymes on the surface of the transducers, layer-by-layer (LbL) self-assembly based on electrostatic interaction with polyelectrolytes of opposite charge stands out due to its simplicity and reproducibility. Aims: The aim of the work was to develop an electrochemical glucose biosensor by LbL assembly of a new functionalized chitosan polycation and the enzyme glucose oxidase (GOx). Methods: Chitosan was chemically functionalized with glucose by the Maillard reaction. The resulting polycation, named G-Chit, is soluble in the medium compatible with the enzyme. The bioelectrode was obtained by alternating adsorption of G-Chit and GOx onto carbon paste electrodes. By selecting the number of bilayer of G-Chit/GOX, the enzyme concentration, and the pH, the electroanalytical performance of the biosensor was optimized. The electrochemical responses were characterized by cyclic voltammetry and chronoamperometry. Results: Under optimized experimental conditions, the biosensor exhibited a sensitivity of (0.81 ± 0.03) µA mM-1 in a glucose concentration range of (0.18 to 1.75) mM. Discussion: Results indicated that catalytic response increases both with the number of G-Chit/GOx bilayers and the enzyme concentration, obtaining the best responses for 3 bilayers and 2 mg mL-1, respectively, while the optimum working pH value was 7.0. Conclusions: The analytical response of the biosensor was tested in milk samples with negligible matrix effects, suggesting a potential application in other dairy products. Results show that G-Chit appears promising for the immobilization of enzymes.

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42

Ren, Xiangzhong, Qi Zhao, Jianhong Liu, Xun Liang, Qianling Zhang, Peixin Zhang, Zhongkuan Luo, and Yi Gu. "Preparation of Polypyrrole Nanoparticles in Reverse Micelle and Its Application to Glucose Biosensor." Journal of Nanoscience and Nanotechnology 8, no. 5 (May 1, 2008): 2643–46. http://dx.doi.org/10.1166/jnn.2008.18297.

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Polypyrrole nanoparticles were successfully synthesized in cetyltrimethyl ammonium bromide (CTAB)/hexanol/water reverse micelle. The morphology and particle size of the obtained nanoparticles were characterized with transmission electron microscope (TEM) and scanning electron microscopy (SEM). Glucose biosensors were formed with glucose oxidase (GOx) immobilized in conducting composite material consisting of polypyrrole nanoparticles and ethyl cellulose. The effects of reaction conditions such as molar ratio of polypyrrole nanoparticles to ethyl cellulose, working voltage, glucose concentration, temperature and solution pH on the electrochemical response of the GOx electrode were studied. Experimental results showed that the linear range of GOx electrode was 1.0 × 10−6∼6 × 10−3 mol/L and the detection limit was 1.0 × 10−7 mol/L. The electrode exhibited fine repeatability and selectability, and its lifetime was greater than one month. AFM showed that the surface of conducting composite material-glucose oxidase electrode's presents uniform granular after washing paraffin wax with cyclohexane, which was favorable for enzyme-catalyzed reaction.

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43

Yoshida, Kentaro, Yu Kashimura, Toshio Kamijo, Tetsuya Ono, Takenori Dairaku, Takaya Sato, Yoshitomo Kashiwagi, and Katsuhiko Sato. "Decomposition of Glucose-Sensitive Layer-by-Layer Films Using Hemin, DNA, and Glucose Oxidase." Polymers 12, no. 2 (February 4, 2020): 319. http://dx.doi.org/10.3390/polym12020319.

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Glucose-sensitive films were prepared through the layer-by-layer (LbL) deposition of hemin-modified poly(ethyleneimine) (H-PEI) solution and DNA solution (containing glucose oxidase (GOx)). H-PEI/DNA + GOx multilayer films were constructed using electrostatic interactions. The (H-PEI/DNA + GOx)5 film was then partially decomposed by hydrogen peroxide (H2O2). The mechanism for the decomposition of the LbL film was considered to involve more reactive oxygen species (ROS) that were formed by the reaction of hemin and H2O2, which then caused nonspecific DNA cleavage. In addition, GOx present in the LbL films reacts with glucose to generate hydrogen peroxide. Therefore, decomposition of the (H-PEI/DNA + GOx)5 film was observed when the thin film was immersed in a glucose solution. (H-PEI/DNA + GOx)5 films exposed to a glucose solution for periods of 24, 48 72, and 96 h indicated that the decomposition of the film increased with the time to 9.97%, 16.3%, 23.1%, and 30.5%, respectively. The rate of LbL film decomposition increased with the glucose concentration. At pH and ionic strengths close to physiological conditions, it was possible to slowly decompose the LbL film at low glucose concentrations of 1–10 mM.

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44

Salusjärvi, Tuomas, Nisse Kalkkinen, and Andrei N. Miasnikov. "Cloning and Characterization of Gluconolactone Oxidase of Penicillium cyaneo-fulvum ATCC 10431 and Evaluation of Its Use for Production of d-Erythorbic Acid in Recombinant Pichia pastoris." Applied and Environmental Microbiology 70, no. 9 (September 2004): 5503–10. http://dx.doi.org/10.1128/aem.70.9.5503-5510.2004.

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ABSTRACT A d-erythorbic acid-forming soluble flavoprotein, gluconolactone oxidase (GLO), was purified from Penicillium cyaneo-fulvum strain ATCC 10431 and partially sequenced. Peptide sequences were used to isolate a cDNA clone encoding the enzyme. The cloned gene (accession no. AY576053 ) exhibits high levels of similarity with the genes encoding other known eukaryotic lactone oxidases and also with the genes encoding some putative prokaryotic lactone oxidases. Analysis of the coding sequence of the GLO gene indicated the presence of a typical secretion signal sequence at the N terminus of GLO. No other targeting or anchoring signals were found, suggesting that GLO is the first known lactone oxidase that is secreted rather than targeted to the membranes of the endoplasmic reticulum or mitochondria. Experimental evidence, including the N-terminal sequence of mature GLO and data on glycosylation and localization of the enzyme in native and recombinant hosts, supports this analysis. The GLO gene was expressed in Pichia pastoris, and recombinant GLO was produced by using the strong methanol-induced AOX1 promoter. In order to evaluate the suitability of purified GLO for production of d-erythorbic acid, we immobilized it on N-hydroxysuccinimide-activated Sepharose and found that the immobilized GLO retained full activity during immobilization but was rather unstable under reaction conditions. Our results show that both soluble and immobilized forms of GLO can, in principle, be used for production of d-erythorbic acid from d-glucono-δ-lactone or (in combination with glucose oxidase and catalase) from glucose. We also demonstrated the feasibility of glucose-d-erythorbic acid fermentation with recombinant strains coexpressing GLO and glucose oxidase genes, and we analyzed problems associated with construction of efficient d-erythorbic acid-producing hosts.

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45

Golikova, E. P., N. V. Lakina, O. V. Grebennikova, V. G. Matveeva, and E. M. Sulman. "A study of biocatalysts based on glucose oxidase." Faraday Discussions 202 (2017): 303–14. http://dx.doi.org/10.1039/c7fd00042a.

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Анотація:

During this work, we studied the possibility of glucose oxidase (GOx) covalent immobilization on a modified inorganic support. A series of GOx-based biocatalysts was synthesized by crosslinking the enzyme to a surface of modified silica or alumina. Polyelectrolyte layers were used as modifiers for the silica and alumina surfaces. These layers promote tight binding of the GOx to the support. The biocatalyst’s activity and stability were studied using an oxidation reaction of d-glucose to d-gluconic acid. It was found that GOx immobilized on the modified SiO₂ using glutardialdehyde as a crosslinking agent was the most active and stable catalytic system, showing an 85% yield of gluconic acid. A study of the synthesized biocatalyst structure using FTIR spectroscopy showed that the enzyme was covalently crosslinked to the surface of an inorganic support modified with chitosan and glutardialdehyde. In the case of SiO₂, the quantity of the immobilized enzyme was higher than in the case of Al₂O₃.

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Лакина, Наталия Валерьевна, Валентин Юрьевич Долуда, Михаил Геннадьевич Сульман, Маргарита Евгеньевна Лакина, and Артем Михайлович Сивенок. "STUDY OF THE ACTIVITY OF A COMPLEX OF REDOX ENZYMES TO IMPROVE THE PERFORMANCE OF BIOFUEL CELL ELECTRODES." Вестник Тверского государственного университета. Серия: Химия, no. 4(42) (December 21, 2020): 37–44. http://dx.doi.org/10.26456/vtchem2020.4.4.

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Анотація:

В работе представлен обзор способов получения биоэлектродов на основе ферментных комплексов глюкоокидазы и пероксидазы в реакциях по окислению глюкозы. Показано, что пероксидаза, нанесенная на поверхность биокатода, увеличивает энергетическую эффективность биотопливных элементов за счет превращения пероксида водорода, образующегося при окислении D-глюкозы, - ингибитора электродной реакции. Экспериментальная часть работы содержит данные по измерению ферментативной активности окислительно-восстановительного комплекса глюкооксидазы и пероксидазы при хранении. Показано, что активность такого комплекса остается стабильной в течение длительного времени. Полученные данные сопоставимы с зарубежными исследованиями и даже немного превышают представленные величины активностей. Высокую ферментативную активность можно объяснить оптимальным соотношением количеств применяемых окислительно-восстановительных ферментов. В дальнейшем, полученные модифицированные комплексы ферментов могут быть рекомендованы для повышения эффективности биотопливных элементов. This paper presents an overview of methods for producing bioelectrodes based on the enzyme complexes of glucose oxidase and peroxidase for glucose oxidation reactions used in biofuel cells. It is shown that while using peroxidase in biocatode construction the working potential of the reaction increases due to the conversion of main reaction inhibitor - hydrogen peroxide formed during the D-glucose oxidation. The experimental part of the work contains data on changes in the enzymatic activity of the redox complex of glucose oxidase and peroxidase in long-time period. It is shown that the activity of such complex remains stable for a long time. The data obtained are comparable with foreign studies and even slightly exceed the presented values of activities. High enzymatic activity can be explained by the optimal ratio of the amounts of oxidant-reducing enzymes used. In the future, the resulting modified enzyme complexes can be recommended for increasing the efficiency of biofuel cells.

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47

Ji, Jungyeon, Han-Ik Joh, Yongjin Chung, and Yongchai Kwon. "Glucose oxidase and polyacrylic acid based water swellable enzyme–polymer conjugates for promoting glucose detection." Nanoscale 9, no. 41 (2017): 15998–6004. http://dx.doi.org/10.1039/c7nr05545e.

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Анотація:

Glucose oxidase and polyacrylic acid based conjugate shows superior catalytic activity due to its high water swellability. The conjugate absorbs many glucose molecules with rapid transfer rate. Desirable reactions are accordingly promoted.

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48

Elakkiya, Rajasekaran, and Govindhan Maduraiveeran. "A three-dimensional nickel–cobalt oxide nanomaterial as an enzyme-mimetic electrocatalyst for the glucose and lactic acid oxidation reaction." New Journal of Chemistry 43, no. 37 (2019): 14756–62. http://dx.doi.org/10.1039/c9nj01291e.

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Анотація:

Here we demonstrate a highly porous three-dimensional nickel–cobalt oxide (NiCo₂O₄) nanomaterial as a potential glucose oxidase (GOx) enzyme-mimicking catalyst for the electrochemical oxidation of glucose and lactic acid in alkaline medium.

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49

Nothling, Mitchell D., Thomas G. McKenzie, Isaac A. Eastland, Hao-Che Chien, Joe Collins, Anne S. Meyer, and Greg G. Qiao. "Self-deoxygenating glassware." Chemical Communications 55, no. 59 (2019): 8544–47. http://dx.doi.org/10.1039/c9cc03477c.

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50

He, Bao Shan, Na Gao, Fang Wei, and Qi Yu Lu. "Study on Determination of Glucose in Amylofermentation Liquid Using Ultraviolet Spectrophotometry." Advanced Materials Research 538-541 (June 2012): 2434–37. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.2434.

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Анотація:

In the presence of glucose oxidase, glucose in samples was oxygenated to hydrogen peroxide, the solution turned from colourless to yellow upon the reaction of potassium titanyl oxalate to the generated hydrogen peroxide. Using ultraviolet spectrophotometry, a new optical method for detecting glucose in amylofermentation liquid has been established. Results demonstrated that glucose concentrations were proportional to absorbance at the maximum absorption wavelength of 380 nm. A favorable linearity was presented in the range of 1 mmol/L to 60 mmol/L. The linear coeffciency was 0.993. This method was simple, reliable, and could be used for determing glucose in samples.

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