Sucrose periodate method

No oxidation products of sucrose other than those produced by degradation have been described. Oxidation of sucrose with periodic acid has been carried out, but neither the method nor the products need to be considered for the present purpose. 

Formaldehyde is produced by the periodate oxidation of certain carbohydrates, and, aldiough there has as yet been no report of a gas-liquid chromatographic determination of formaldehyde obtained in this way, formaldehyde has been so determined in other contexts. Mixtures of formaldehyde and medianol have been analyzed, columns of acetyl-ated polyesters or sucrose octaacetates being used. The system formaldehyde-water-methanol in which the concentration of formaldehyde was varied from 0.06 to 46.1% was examined by use of a column of Porapak N, and references to previous methods of determination were given. K. Jones evaluated a wide range of supports and liquid phases for analyzing aqueous formaldehyde. ... 

The above structure is confirmed by the results obtained by periodic acid oxidation 93), Sucrose consumes three moles of periodic acid, and one mole of formic acid is formed. (See earlier discussion in this chapter.) After bromine oxidation of the tetraaldehyde and subsequent hydrolysis, hydroxy-pyruvic, D-glyceric, and glyoxylic acids are obtained. (For a discussion of this method see p. 215.)... 

Hydrolysis and other Reactions and Features.—A. novel method for following the add catafysed hydrolysis of sucrose and lactose involves measurement of the rate of reaction of periodate with quenched aliquot portions of the solutions using a periodate>sensitive electrode. In this way sucrose could be determined in the presence of other carbohydrates in the range 0.01-0.1 M, and the method was applied to food products. The glycosidic hydrolysis of fluorenone ketal (107), which serves as a nucleoside glycosylase enzyme model, has been shown to be intramolecularly catalysed by comparison with analogous compounds. ... 

A fast and reliable HPLC method has been developed to follow the course of the periodate oxidation of sucrose as a function of periodate used. Two intermediate sucrose dialdehydes were formed as well as the final tetra-aldehyde compound. ... 

Add about 25 ml of boiled-out distilled water to about 0.5 g accurately weighed (by difference method) lime sample taken in an iodine titration flask and boil for 5-10 minutes. Cool, add a few clean dry glass beads and about 100 ml of a 10% sucrose solution. Stopper the flask and shake for 1 minute after every 5 minutes for a period of half an hour. Filter, by suction, through a Buchner funnel. Wash the residue 3-4 times with 10-ml portions of a 5% sucrose solution. Collect the filtrate and washings in a 250-ml measuring flask and make up to the mark with boiled-out distilled water. Take 50 ml of this solution in a titration flask. Add 2 drops of phenolphthalein indicator and titrate with N/10 HCI solution until the pink coiour disappears. Take concordant readings. 

The exposure time and sampling period shonld be defined in the protocol. The normal exposure time is 24 h. Longer duration may result in membrane deterioration and requires membrane integrity to be carefully checked. Barrier integrity should be checked using a suitable method. This is achieved by either measuring the penetration of a marker molecule, e.g. tritiated water, caffeine or sucrose, or by physical methods like TEWL or TER measurements. Data obtained should be reported. 

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