Effects of deacetylation variables of chitin on characteris of chitosan products in relation to tablets-disintegrating properties

Abstract

Chi tin was deacetylated by different conditions to produce chitosans having different degree of deacetylation and their physical properties in relation to tablet-disintegrating properties (hydration capacity, swelling capacity, and rate of water uptake) were investigated. The variables in the deacetylation process included : reaction time, temperature, and atmospheric condition. Chitosans obtained had the degree of deacetylation ranged from 67 to 80%. To produce high molecular weight chitosan, the deacetylation should be carried out at low temperature under nitrogen atmosphere. When the reaction time increased, the degree of deacetylation of chitosan products increased but the molecular weight decreased. Both degree of deacetylation and molecular weight of chitosans did not apparently affect their physical properties observed. The reaction time and atmospheric condition were not also influencing-factors on these physical properties. Only the reaction temperature affected the characteristics of chitosan products. Chitosan deacetylated at low temperature (room temperature) exhibited higher hydration and swelling capacity, and the slower rate of water uptake than those prepared at high temperature (110℃). Paracetamoltalbets containing chitin or chitosan were produced. Their disintegration time were determined both in water and in 0.1 N.HCl. No significant difference was observed when disintegration time was evaluated in water. Disintegration times of tablets containing chitin in water and in 0.1N. HCl were not different, whereas disintegration times of tablets containing chitosan in 0.1 N. HCl were longer than those in water. Moreover, the higher the degree of deacetylation, the longer the disintegration time.