Qunantitative Determination of the Uronic Acid Composition of Alginates.

Abstract

A method for quantitative determination of the uronic acid composition of alginates is described. The method is based on hydrolysis of the alginate with 80% sulphuric acid at 20[degree]C, followed by treatment with 2 N acid at 100[degree]C, and separation of the uronic acids in the hydrolysate by chromatography on an anion exchange column. The amounts of the different uronic acids are determined by the orcinol reaction. The loss of uronic acids in the different steps in the procedure has been investigated and a factor correcting for the different rate of breakdown of guluronic and mannuronic acid is introduced.