Improvement and Determination of the Degree of Deacetylation of Chitosan via Potentiometric Titration Method and Infrared Spectroscopy

Document Type : Research Article


1 School of Chemical, Petroleum and Gas Engineering, Shiraz University, Shiraz I.R. IRAN

2 Department of Chemical and Engineering, University of Sistan and Baluchestan, P.O. Box 98164-161 Zahedan, I.R. IRAN


The Degree of Deacetylation (DD) of chitosan plays a main role in its physical, chemical and biological properties. Hence, in this study, low-viscous, medium, and high (impure and improved) molecular weight chitosan were used to determine DD, using a simple and exact method, The DDs of chitosan were determined by the fourier transform infrared spectroscopy (Baseline-a and b ) and linear potentiometric titration. Thie concluded results were compared using Root-Mean-Square Deviation (sRMSD) whereby an agreement between the linear potentiometric titration and fourier transform infrared spectroscopy (Baseline-a) were shown. In presented method, for purifying impurities and improving DD of the high molecular chitosan, DD was noticeably increased from 60.1 to 92.7 %. The analysis of chitosan's DD represented the raise of DD in the presence of the increase of viscosity and molecular weight of chitosan.


Main Subjects

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