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526-95-4Relevant articles and documents
The reduction of Cr(VI) to Cr(III) by the α and β anomers of D-glucose in dimethyl sulfoxide. A comparative kinetic and mechanistic study
Signorella, Sandra,Lafarga, Rubén,Daier, Verónica,Sala, Luis F.
, p. 127 - 135 (2000)
The reduction of Cr(VI) by α-D-glucose and β-D-glucose was studied in dimethyl sulfoxide in the presence of pyridinium p-toluensulfonate, a medium where mutarotation is slower than the redox reaction. The two anomers reduce Cr(VI) by formation of an intermediate Cr(VI) ester precursor of the slow redox step. The equilibrium constant for the formation of the intermediate chromic ester and the rate of the redox steps are different for each anomer. α-D-Glucose forms the Cr(VI)-Glc ester with a higher equilibrium constant than β-D-glucose, but the electron transfer within this complex is slower than for the β anomer. The difference is attributed to the better chelating ability of the 1,2-cis-diolate moiety of the α anomer. The Cr(V) species, generated in the reaction mixture, reacts with the two anomers at a rate comparable with that of Cr(VI). The EPR spectra show that the α anomer forms several linkage isomers of the five-coordinate Cr(V) bis-chelate, while β-D- glucose affords a mixture of six-coordinate Cr(V) mono-chelate and five- coordinate Cr(V) bis-chelate. The conversion of the Cr(V) mono- to bis- chelate is discussed in terms of the ability of the 1,2-cis- versus 1,2- trans-diolate moieties of the glucose anomers to bind Cr(V). (C) 2000 Elsevier Science Ltd.
Au/Pt-Egg-in-Nest Nanomotor for Glucose-Powered Catalytic Motion and Enhanced Molecular Transport to Living Cells
Kumar, Amit,Kumari, Nitee,Kwon, Taewan,Lee, In Su,Lim, Jongwon,Son, Chang Yun
, p. 17579 - 17586 (2021)
Nanostructures converting chemical energy to mechanical work by using benign metabolic fuels, have huge implications in biomedical science. Here, we introduce Au/Pt-based Janus nanostructures, resembling to “egg-in-nest” morphology (Au/Pt-ENs), showing enhanced motion as a result of dual enzyme-relay-like catalytic cascade in physiological biomedia, and in turn showing molecular-laden transport to living cells. We developed dynamic-casting approach using silica yolk-shell nanoreactors: first, to install a large Au-seed fixing the silica-yolk aside while providing the anisotropically confined concave hollow nanospace to grow curved Pt-dendritic networks. Owing to the intimately interfaced Au and Pt catalytic sites integrated in a unique anisotropic nest-like morphology, Au/Pt-ENs exhibited high diffusion rates and displacements as the result of glucose-converted oxygen concentration gradient. High diffusiophoresis in cell culture media increased the nanomotor-membrane interaction events, in turn facilitated the cell internalization. In addition, the porous network of Au/Pt-ENs facilitated the drug-molecule cargo loading and delivery to the living cells.
Glucose biosensor based on new carbon nanotube-gold-titania nano-composites modified glassy carbon electrode
Wu, Yue-Li,Li, Qi-Wei,Zhang, Xiao-Lu,Chen, Xiao,Wang, Xue-Mei
, p. 1087 - 1090 (2013)
In this paper, a novel biosensor was prepared by immobilizing glucose oxidase (GOx) on carbon nanotube-gold-titania nanocomposites (CNT/Au/TiO 2) modified glassy carbon electrode (GCE). SEM was initially used to investigate the surface morphology of CNT/Au/TiO2 nanocomposites modified GCE, indicating the formation of the nano-porous structure which could readily facilitate the attachment of GOx on the electrode surface. Cyclic voltammogram (CV) and electrochemical impedance spectrum (EIS) were further utilized to explore relevant electrochemical activity on CNT/Au/TiO2 nanocomposites modified GCE. The observations demonstrated that the immobilized GOx could efficiently execute its bioelectrocatalytic activity for the oxidation of glucose. The biosensor exhibited a wider linearity range from 0.1 mmol L-1 to 8 mmol L-1 glucose with a detection limit of 0.077 mmol L-1.
Sol-gel encapsulated glucose oxidase arrays based on a pH sensitive fluorescent dye
Yildirim, Nimet,Odaci, Dilek,Ozturk, Gulsiye,Alp, Serap,Ergun, Yavuz,Dornbusch, Kay,Feller, Karl-Heinz,Timur, Suna
, p. 144 - 148 (2011)
Optical glucose oxidase (GOx) arrays based on pH sensitive fluorescent dye (2-(4-tolyl)-4-[4-(1,4,7,10-tetraoxa-13-azacyclopentadecyl)benzylidene] -5-oxazolone) (CPO) has been constructed. The arrays were prepared by spotting of CPO and GOx together with tetraethoxysilane (TEOS)/Chitosan (CHIT) mixture via a microarrayer. After optimization studies, analytical characterization of enzyme arrays were carried out. The fluorescence intensity of the system was linearly correlated to glucose concentration in the range of 1.0-30.0 mM (in potassium phosphate buffer; 2.5 mM at pH 7.0). Furthermore, the developed arrays were used to analyze glucose in some beverages and HPLC was used as a reference method for independent glucose analysis.
Oxidation of d-Glucose to Glucaric Acid Using Au/C Catalysts
Solmi, Stefania,Morreale, Calogero,Ospitali, Francesca,Agnoli, Stefano,Cavani, Fabrizio
, p. 2797 - 2806 (2017)
The reactivity of Au and AuBi nanoparticles supported on activated carbon AC was investigated in the direct oxidation of glucose to glucaric acid. The catalysts were very active, regardless of the Au nanoparticles size, but the catalyst with the smallest average particle diameter was the least selective to glucaric acid because of the enhanced consecutive oxidative degradation of the intermediately formed gluconic acid. The reaction network included the fast oxidation of glucose to gluconic acid, which was the only primary product, and its consecutive oxidation into either glucaric acid or lighter mono and dicarboxylic acids. The best glucaric acid yield obtained with a AuBi/AC catalyst (Au/Bi 3:1) was 31 %, with 18 % residual gluconic acid. The control of reaction parameters was essential to achieving the best selectivity. Specifically, the glucose concentration turned out to be a critical parameter in relation to O2 pressure and to glucose/metal ratio.
Label-free Si quantum dots as photoluminescence probes for glucose detection
Yi, Yinhui,Deng, Jianhui,Zhang, Youyu,Li, Haitao,Yao, Shouzhuo
, p. 612 - 614 (2013)
Si quantum dots have been demonstrated to be environmentally friendly photoluminescence probes and their fluorescence was quenched by H 2O2 that was produced from the glucose oxidase-catalyzed oxidation of glucose. This strategy could be used to detect glucose with high sensitivity and selectivity.
Diverse applications of TMB-based sensing probes
Huang, Li,Cao, Ying-Juan,Sun, Xiang-Ying,Liu, Bin,Shen, Jiang-Shan
, p. 5667 - 5676 (2018)
Extending the research on 3,3′,5,5′-tetramethylbenzidine (TMB) and its derivatives in analytical chemistry is important, considering that TMB is widely used as an enzyme catalytic substrate. In this work, two TMB derivatives, TMBS and TMBB, were synthesized via a facile and one-step condensation reaction between the -NH2 group of TMB and the -CHO group of salicylaldehyde or benzaldehyde. Because at low pH the two Schiff base compounds can release TMB which can emit strong fluorescence, the probes could show dual-modal signal responses, fluorescence and UV-vis absorption, towards the pH. Practical applications of pH sensing in Chinese rice vinegar and lemon juice samples were successfully demonstrated. On the basis of these findings, a catalytic chromogenic reaction was developed to monitor the pH with the naked eye, too. Furthermore, considering the chemical equilibrium reaction between CO2 and H2O and that glucose oxidase (GOD) can catalyse the dehydrogenation and oxidation reaction of β-d-glucose to produce gluconic acid, both of which can result in lowering the pH values of the two Schiff base systems, highly sensitive and selective dual-modal sensing systems for detecting CO2 and β-d-glucose have also been successfully established. Therefore, the two synthesized TMB derivatives can demonstrate their robust application potential.
Structure sensitivity and kinetics of D-glucose oxidation to D-gluconic acid over carbon-supported gold catalysts
Oenal,Schimpf,Claus
, p. 122 - 133 (2004)
The heterogeneously catalyzed oxidation of D-glucose to D-gluconic acid over Au/C catalysts has been studied. A series of Au/C catalysts were prepared by the gold sol method with different reducing agents and different kinds of carbon support providing Au mean particle diameters in the range 3-6 nm. The activities of these catalysts with respect to D-glucose oxidation were compared, and several aspects influencing activity, especially Au particle size, were discussed. The influence of reaction conditions (T=30-90°C, pH 7.0-9.5) on the kinetics of the D-glucose oxidation has been examined using the most active Au/C catalyst. By a detailed analysis of all reaction products under different reaction conditions, a reaction network of the D-glucose oxidation is presented, and a reaction mechanism for D-glucose oxidation that explains the influence of pH on reaction rate is proposed. Ensuring that D-glucose oxidation takes place in the kinetic regime (sufficient stirring rate and airflow rate), a semiempirical model based on a Langmuir-Hinshelwood-type reaction pathway is assumed. At 50°C and pH 9.5 kinetic parameters were calculated by an optimization routine. The resulting concentration courses of D-glucose and D-gluconic acid were in good agreement with the experimental data. All experiments were carried out in a semibatch reactor under pH control at atmospheric pressure.
Behavior of IrCl3 as a Homogeneous Catalyst on the Oxidation of N-Acetylglucosamine in Acid Medium and Uncatalyzed Reaction in Alkaline Medium with Bromamine-B: Exploration of Kinetic, Mechanistic and Catalytic Chemistry
Shankarlingaiah, Dakshayani,Puttaswamy
, p. 424 - 437 (2018)
Abstract: The experimental rate laws for the oxidation of N-acetylglucosamine with bromamine- B are: ? d[BAB]/dt = k/ [BAB]1 [GlcNAc]0.69 [HClO4]?0.76 [IrCl3]0.48 [BSA]?0.33 in acid medium and –d[BAB]/dt = k/?[BAB]1 [GlcNAc]1 [NaOH]0.79 in alkaline medium. The IrCl3 catalyzed reaction is thirteen fold faster than uncatalyzed reaction. Appropriate mechanisms and rate laws were deduced. Graphical Abstract: The reaction of N-acetylglucosamine with Bromamine-B in acid and alkaline medium is [Figure not available: see fulltext.].
Efficient Oxidation of Glucose into Gluconic Acid Catalyzed by Oxygen-Rich Carbon Supported Pd Under Room Temperature and Atmospheric Pressure
Liu, Anqiu,Huang, Zhong,Wang, Xiaochen
, p. 2019 - 2029 (2018)
Abstract: A new method has been developed for the oxidation of glucose into gluconic acid over Pd/C catalysts under the room temperature and atmospheric pressure. The carbon support was prepared by the hydrothermal treatment of renewable glucose, thus contained abundant active oxygen species. The Pd/C catalyst showed high catalytic activity towards the oxidation of glucose into gluconic acid. A 100% glucose conversion and a 98% gluconic acid yield were attained within 2?h at 0.1?MPa and room temperature. Structural analysis showed that the Pd paricle sizes of the catalysts were in the range of 10.1–16.2?nm influenced by the loading of Pd. The structure/size study showed that the catalyst with optimal particle size of 10.9?nm exhibited the highest TOF (0.2388?molglucose?molPd/s). The catalyst showed no significant loss of activity after recycled for four times. Graphical Abstract: [Figure not available: see fulltext.].
