Electrooxidation glucose

For the oxidation of glucose to Ca gluconate, an indirect electrooxidation via the intermediate formation of sodium hypobromite is effective [12] ... 

Thin-layer Studies. The thin-layer electrochemical system was developed to address the lack of sensitivity of a preliminary bulk amperometric activity assay (77). The first set of thin-layer studies was taken to characterize the thin-layer cells in soluble enzyme solutions and to determine if there were any interferences to the detection of hydrogen peroxide. Preliminary thin-layer studies (23) indicated that the oxidation of hydrogen peroxide could be detected at approximately 1080 mV with only minimal interference from the oxidation of glucose by gold. The addition of chloride ion to the solution further suppressed the glucose electrooxidation interference. 

As shown in different works,41 65-71 the mechanism of glucose electrooxidation on platinum is similar to that on gold electrode. The primary and main reaction product remains 8-gluconolactone that is transformed into gluconate by hydrolysis. 

The main aim of these studies is how to enhance the oxidation of glucose therefore, upd studies are also involved. As in the previous cases, the role of the crystalline surface structure of platinum electrodes in the electrooxidation is also studied. A series of studies was carried out by Wilde and Zhang using EQCM technique, in the presence and absence of adatoms in both acid and alkaline media. Unfortunately, owing to the very nature of the technique used, only phenomenological conclusions can be drawn from these latter studies and no information is furnished about the nature of the adsorbed species. The same refers to some other studies. ... 

Among the first systematic studies on the electrolytic oxidation of n-glucose and certain other carbohydrates may be mentioned work by Loeb and Neuberg and coworkers. In experiments on the electrooxidation of D-glucose in solution in 5 aqueous sulfuric acid, using a lead anode, a temperature of <16°, and a platinum cathode, Loeb obtained, on the one hand, oxidation products (n-arabinonic acid and D-glucaric acid), and, on the other hand, fragmentation products (d-arabinose and formaldehyde) which were further oxidized to o-arab-inonic acid and n-arabinaric acid, and formic acid, respectively. 

The mediatorless electrooxidation of glucose has been realized in the presence of glucose oxidase adsorbed on an electrode made of organic metal. Oxidation occurs at E, > 0.5 V and the electrode preserved its activity for more than 100 days. 

I. Becerik, S. Suzer, and F. Kadirgan, Platinum-palladium loaded pol)fpyrrole film electrodes for the electrooxidation of D-glucose in neutral media, J. Electroanal. Chem., 476,171-176 (1999). 

Gutierrez, F.A., Rubianes, M.D., and Rivas, G.A. (2013) Adsorption and electrooxidation of DNA at glassy carbon electrodes modified with multiwall carbon nanotubes dispersed in glucose oxidase. Electroanalysis, 25, 1135—1142. 

The direct electrooxidation of aqueous E>-g]uconic acid to l>arabinose on graphite has been performed in a very simple apparatus which may be suitable for practical application. The electrocatalytic oxidation of sucrose on smooth, lead-modified platinum electrodes has been examined with a view to finding experimental conditions for the selective electrosynthesis of value-added compounds. A paper in Bulgarian on the electrooxidation of diacetone-L-sorbose at low current densities in a nickel oxide electrolizer has been publi ed. The influence of the rize of palladium particles and their location on the support on their activity in the oxidation of glucose has been examined. An investigation of the effect of tonperature and pH on the platinum-catalysed oxidation of sucrose showed that changes in temperature affect mainly the reaction rate, where changes in pH alter the selectivity. ... 

Villagra E, Bedioui E, Nyokong T, Carlos Canales J, Sancy M, Paez MA, Costamagna J, Zagal JH (2008) Tuning the redox properties of C0-N4 macrocyclic complexes for the catalytic electrooxidation of glucose. Electrochim Acta 53 4883-4888... 

Miniaturization requires a high current density, which in turn requires rapid electrooxidation of glucose and efficient collection of the current. The electrode kinetics is fast when the redox polymer conducts electrons and is highly permeable to both glucose and gluconolactone [5-8]. Cross-linked poly[(N-vinyl-imi-dazole) Os(bipyridine)2Cl]+ + [9] and poly[(4-vinyl-pyridine)Os (bipyridme)2 C11+/2+ [10] are examples of GOX-wiring redox polymers. 

Serum contains electrooxidizable ascorbate, urate, and acetaminophen. These may contribute to the measured current, and thereby prevent one-point calibration of the implanted electrodes. To reduce the rate of the electrooxidation of these compounds, their flux to the wired enzyme layer is reduced by a special micromembrane [11]. The same membrane also reduces, to a lesser extent, the flux of glucose, thereby extending, at least to 30 mM, the linear part of the curve representing the dependence of the electrooxidation current on glucose concentration [11]. The required micromembranes of 5 x 10 cm area are synthesized in situ on the wired GOX layers by sequentially adsorbing polyanions and polycations. The micromembrane allows the simultaneous adjustment of the linear... 

The role of the crystalline surface structure, and in particular long range surface order, of platinum electrodes in the electrooxidation of D-glucose in acidic media has been discussed. Papers have been published on the effects of adsorbed anions on the oxidation of D-glucose on gold single crystal electrodes, and on the oxidation of D-sorbose and 2,3 4,6-di-0-isopropylidene-a-L-sorbose by air over supported platinum and palladium catalysts. ... 

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