Application of Paper Partition Chromatography to the Separation of the Polyhydric Alcohols

Abstract

BAKER¹ has described the isolation of dulcitol, a non-reducing sugar alcohol, from the exudate of the leaves of Euonymus japonica. An investigation of this exudate by partition chromatography on strips of filter paper, employing the usual solvents for sugar analysis, revealed that dulcitol gives rise to a discrete dark brown spot on the paper chromatogram when it is sprayed with an ammoniacal solution of silver nitrate and heated. Other polyhydric alcohols, such as mannitol, sorbitol, glycerol and ethylene glycol, also reduce ammoniacal silver nitrate under these conditions, a most surprising and unpredictable result. In view of the importance of partition chromatography for the analysis of intimate mixtures of the reducing sugars², an examination of the properties of the polyhydric alcohols on the paper chromatogram was necessary in order to avoid any confusion between these closely related substances. It is of interest to note that Partridge³ has encountered inositol, a cyclic hexitol, along with glucose and fructose in an extract of the fœtal blood of sheep, since he found that it also gives rise to a discrete brown spot on the paper chromatogram with the ammoniacal silver nitrate reagent.