PURPOSE: To prepare chitosan powder having uniform particle diameters by simple procedures, by dissolving chitosan in an acid, preparing a chitosan suspension by adding an alkali to the soln., submitting the suspension to freezing and thawing so as to make chitosan into particles, desalting the resulting suspension and drying it.
CONSTITUTION: Chitosan is dissolved in an acid and the soln. is mixed with an alkali to prepare a chitosan suspension, which is submitted to freezing and thawing so as to make chitosan into particles. The suspension after the freezing and thawing is desalted with deionized water and then dried. The acid soln. used for dissolving chitosan should pref. be freed of insol. matters by filtration or other means prior to the addition of the alkali. The drying should be made pref. by means of freeze-drying or drying under reduced pressure after replacement with an org. solvent.
Adachi, Tsuneyasu
Enomoto, Mikiji
