Ascorbic acid paper chromatography

Chromatographic methods, notably hplc, are available for the simultaneous deterrnination of ascorbic acid as weU as dehydroascorbic acid. Some of these methods result in the separation of ascorbic acid from its isomers, eg, erythorbic acid and oxidation products such as diketogulonic acid. Detection has been by fluorescence, uv absorption, or electrochemical methods (83—85). Polarographic methods have been used because of their accuracy and their ease of operation. Ion exclusion (86) and ion suppression (87) chromatography methods have recently been reported. Other methods for ascorbic acid deterrnination include enzymatic, spectroscopic, paper, thin layer, and gas chromatographic methods. ExceUent reviews of these methods have been pubHshed (73,88,89). 

Evidence for the production of ascorbic acids is that, after irradiation, the solution was able to decolorize solutions of 2,6-dichlorophenolindophenol and to produce a red color with an alkaline solution of triphenyltetrazolium chloride. The solution also displayed an absorption maximum at 245 m/u similar to that of L-ascorhic acid, and paper chromatography indicated the presence of a product running identically with L-ascorbic acid. The yield of the ascorbic acid was a function of the concentration, rising from G 0.16 at 5 X 10 ilf to G 0.95 at 4 X 10 M for a dose of 2.8 X 10 e.v. ml. of x-rays. The route to the ascorbic acid from the lactone may involve abstraction of a hydrogen atom at C-2 or C-3, followed by enoliza-tion. 

Ascorbate Levels in Tissues. Several tissues were dissected from M. sexta and analyzed for L-ascorbic acid by high performance liquid chromatography (HPLC) (Figure 2), paper chromatography, or the dinitrophenylhydrazine method (5). As anticipated, L-ascorbic acid was... 

The acid is reduced by sugars and by ascorbic acid to a dye, and it can be used for microdetermination of sugar components of polysaccharide hydrolyzates after separation by paper chromatography. ... 

The chemical and physical methods in common use are nonspecific insofar as they determine the stereoisomers of L-ascorbic acid and other closely related enediol compounds. While these compounds are rare in natural products, there is frequently need for exact chemical identification of the substance being measured. One procedure which has been used is isotopic dilution and reisolation (DIO). A more generally useful procedure for the identification is paper chromatography (M9). Subsequent quantitative analyses of the resolved spots can be carried out (C7). 

TLC has been used to determine ascorbic acid in foods, pharmaceutical preparations, and biological fluids. Paper chromatography was used to separate ascorbic and dehydroascorbic acid in plant extracts, and the spots were visualized using 2,5-dichlorophenol indophenol (Bui-Nguyen, 1985). This procedure is probably applicable to TLC on cellulose. 

Paper and thin-layer chromatography (TLC) was applied in early analytical studies to increase selectivity in the analysis of ascorbic acid and other similar chemical compounds. Nowadays these methods have little if any qualitative or quantitative use. However, TLC has proven to have some advantages in the analysis of vitamin C compounds, especially in pharmaceuticals, which often consist of a... 

In addition to these acids, ascorbic acid, dehydroascorbic acid, glucuronic acid and furan-2,5-dicarboxylic acid also occur among the aliphatic acids in urine. Knowledge of the aromatic acids again improved with the introduction of paper chromatography (Armstrong et al.y 1956), and acids reported to occur... 

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