A review of several reported procedures to determine the degree of N-acetylation for chitin and chitosan using infrared spectroscopy

Several methods have been already developed to determine the degree of N-acetylation, DA, for chitin and chitosan. In this article, determination of the DA for chitin and chitosan by various procedures using infrared spectroscopy technique (IR) has been reviewed. The information provided in this article describes various parameters affecting the accuracy of the DA values and allows one to choose an appropriate procedure to determine the DA for chitin/chitosan samples. IR technique was used for a qualitative or quantitative evaluation of DA. Determination of several absorption ratios using only one spectrum and their evaluation by a statistical method was the best procedure for a quantitative analysis, but the procedure is relatively long and time-consuming. (c) 2007 Published by Elsevier Ltd.