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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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Starch dialdehyde. IV. Changes during storage and methods of determination
K. Tihlárik, Š. Batáryová, K. Babor, and V. Kaláč
Institute of Chemistry, Slovak Academy of Sciences,
809 33 Bratislava
Abstract: The routine methods currently used for determination of percentage of oxidized
glucose units in starch dialdehyde (i.e. the method based on oxime formation, determination of rapid alkali consumption, formation of corresponding /?-nitrophenylhydrazone,
and the method of additional periodate oxidation) were compared and a new method
based on the oxidation of starch dialdehyde sample by iodine in alkaline solution has
been developed.
It has been observed that depending upon the length of storage the starch dialdehyde
undergoes changes resulting in a decreasing percentage of oxidized glucose units in the
product. The relative value of this decrease depends on the method used for determination of the degree of oxidation.
The only method giving adequate information on the number of actually effective
aldehyde groups in aged samples of starch dialdehyde is the oximation method.
The decrease in the number of determinable aldehyde groups denoted as "aging" is
reversible. The conditions have been found at which practically the original values can be
restored.
Full paper in Portable Document Format: 305a682.pdf
Chemical Papers 30 (5) 682–692 (1976)
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