Sugars polarography

In practice, polarography has been most frequently used for detection of carbohydrates in the sugar industry and in sugar products. ... 

The development of electrochemical procedures for industrial synthesis of alditols was initiated in the 1920 s and the literature on electrochemistry of carbohydrates, from both synthetic and analytical viewpoints, is extensive. However, it is probably true to state that the average carbohydrate chemist has scant knowledge of the literature on preparative aspects of electrochemistry, or on polarography of sugars. The Chapter by Fedoronko (Bratislava) should, therefore, fill an important need by integrating the work on the electrochemistry of carbohydrates that has matured during several decades. 

In short, polarography can be used for the analysis of C—N, C—O, N—O, O—O, S—S, and C—S groups and for the analysis of heterocyclic compounds. Also, many important biochemical species are electroactive, such as vitamin C (ascorbic acid), fumaric acid, vitamin B factors (riboflavin, thiamine, niacin), antioxidants such as tocopherols (vitamin E), A-nitrosamines, ketose sugars (fructose and sorbose), and the steroid aldosterone. 

When manganese(III) ions are used to induce reaction between hypo-bromous acid and sugars, oscillations appear in the potential of a platinum electrode in the solution. Nine common mono- and di-sacccharides were studied by such polarography and sustained oscillations of the Belousov-Zhabotinsky type were noted when a nitrogen 38 13... 

Differential pulse polarography cleaves the glycosldlc bond of daunorubicin and several derivatives as Illustrated in Scheme 6, the reaction rate depending on the orientation of the sugar to the TC-system. ... 

The studies on the adsorption of model compounds, synthetic polynucleotides and degradation products of nucleic acids with the aid of a.c. polarography [98-101] indicate that all three basic constituents of nucleic acids, i.e., bases, sugars and phoshoric acid participate in the adsorption of nucleic acids at mercury electrodes. The extent of their participation in the adsorption of nucleic acids depends on their secondary structure in the bulk of solution, ionic strength and pH of the medium and the magnitude and sign of the surface charge [99, 102]. 

Several examples of the applications of polarography in these fields have been already mentioned in Chapters VI and VII, viz. determinations of benzene, toluene, naphthalene and phenols in the atmosphere, breath, blood or urine, of amino acids (with particular interest to tyrosine, tryptophane, phenylalanine, histidine and histamine), of ketoacids, ketosteroids, carbon disulphide in air and blood, ethanol, acetoin, sugars and morphine in blood, of lactic acid, mandelic acid in bile and urine, adrenaline and thyroxine in iodinated proteins and last, but not least, of thiol compounds, both soluble and bound in biological materials. A few further examples will be given here. 

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