A new assay of chitosan in the presence of protein by hydrolysis with commercial alpha-amylase.

摘要

A simple and rapid method for the assay of chitosan concentration was developed employing hydrolysis of chitosan by alpha-amylase. The hydrolyzed products were mainly glucosamine, N-acetylated glucosamine, and chitooligosaccharides and were determined colorimetrically using 3,5-dimethylsalicylic acid. The result observed that the absorbance at 540 nm was linear (regression coefficient: 0.9967) with respect to the concentration of chitosan. The content of chitosan determined by this method was comparable with that determined by either colorimetrical method or HPLC method. The new method is specific for estimation of chitosan, particularly in the sample containing protein with high accuracy, and can assay chitosan content up to 3.2 mg/mL.