STUDIES ON THE GLYCOPROTEINS OF THE DOMESTIC FOWL: I. A MODIFICATION OF THE METHOD OF ELSON AND MORGAN FOR THE DETERMINATION OF HEXOSAMINE, AND ITS APPLICABILITY TO TISSUE HYDROLYZATES

Abstract

The method of Elson and Morgan for the determination of hexosamine has been studied spectrophotometrically with the object of applying the method to the analysis of tissue hydrolyzates. It has been shown that it is possible by appropriate blanks to correct for interference due to humin. It has been found necessary (a) to increase the strength of the buffer solution in order to stablize the pH and, in extreme cases, first to neutralize the dried hydrolyzate; and (b) to increase the amount of acetylacetone. These modifications also reduce interference by hydroxyproline to a minimum. The use of an appropriate excess of acetylacetone was found to depress the formation of the secondary chromogen during acetylation. A procedure based on these findings is proposed for the direct determination of hexosamine in acid hydrolyzates of tissues.