Abstract:

Chitosan is the product of chitin deacetylation. Therefore, the degree of deacetylation can be obtained by
determining the content of acetic acid. In this paper, a method was developed to assess the degree of deacetylation of
chitosan by quantitating acetic acid concentration using ion chromatography. The fermented liquid was centrifuged in sterile
centrifuge tubes at 10 000 r/min for 15 min to remove the bacterial cells. Then the supernatant fluid was filtered through a
0.45 μm cellulose acetate membrane and injected into ion chromatography system. Good chromatographic separation was
achieved. This method had good linearity in the range of 0.5–25.0 mg/L and its recoveries ranged from 95.04% to 102.25%,
with relative standard deviation (RSD) lower than 2.99%. It is simple, quick and more accurate as compared with the
traditional titration method and can be used to monitor deacetylation of chitin and optimize deacetylase activity.

Key words: chitosan, chitin, degree of deacetylation, acetic acid, ion chromatography