Book ChapterDOI
Selected methods for the determination of ascorbic acid in animal cells, tissues, and fluids
TLDR
This chapter discusses selected methods for the determination of ascorbic acid in animal cells, tissues, and fluids and suggests that prompt stabilization is especially important in the case of plasma or serum.Abstract:
Publisher Summary This chapter discusses selected methods for the determination of ascorbic acid in animal cells, tissues, and fluids. Methods for determining ascorbic acid are numerous. In general, chemical analyses for the vitamin are divided into two groups; the determination of the reduced form and the determination of the oxidized form. The former group of analyses is usually based upon the oxidation–reduction properties of ascorbic acid. These are widely used as the fundamental reactions in the measurement of vitamin C. The latter group of analyses is usually based upon the oxidation of the ascorbic acid and the subsequent formation of a hydrazone or a fluorophore. Best results are obtained if samples, especially plasma, are quickly stabilized with either trichloroacetic acid or metaphosphoric acid and immediately analyzed. Prompt stabilization is especially important in the case of plasma or serum. The greater stability of ascorbic acid in acid solution is because of the decreased tendency for the hydrolysis of the lactone ring with decreasing pH.read more
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References
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Journal ArticleDOI
The determination of ascorbic acid in whole blood and urine through the 2,4-dinitrophenylhydrazine derivative of dehydroascorbic acid
Joseph H. Roe,Carl A. Kuether +1 more
Journal ArticleDOI
Distribution of ascorbic acid, metabolites and analogues in man and animals.
TL;DR: The availability of labeled AA, metabolites, and analogues has made it possible to follow up the appearance of these compounds or mctabolites thereof in various tissues of animals by means of dissecting the animals with subsequent determination of the radioactive material accumulated by the tissues or by Means of whole-body autoradiography.
Journal ArticleDOI
A rapid micromethod for the determination of ascorbic acid in plasma and tissues.
TL;DR: A rapid simple micromethod for the determination of l -ascorbic acid in plasma and other biological tissues using orthophosphoric acid and ferric iron is presented and can be used to accurately determine 0.1 μg of the vitamin in samples of plasma andOther biological tissues.