PREPARATION METHOD OF WATER-SOLUBLE FREE AMINE CHITOSAN

摘要

PURPOSE: A method for preparing a water-soluble free amine chitosan is provided, to obtain a pure water-soluble free amine chitosan with a molecular weight of 1,000-100,000 Dalton. CONSTITUTION: The method comprises the steps of treating a solution of salts of an organic acid or an inorganic acid of chitosan oligosaccharide with a trialkylamine; adding an organic solvent to the solution to recover the chitosan oligosaccharide by removing an organic acid or an inorganic acid in the form of a trialkylamine salt; and treating the chitosan oligosaccharide solution with an inorganic acid and purifying the solution with an activated carbon/ion exchange resin column. Preferably the organic acid is selected from the group consisting of lactic acid, acetic acid, propionic acid, formic acid, ascorbic acid and tartaric acid; and the inorganic acid is selected from the group consisting of HCl, HNO3 and H2SO4.