Comparative Analysis of Analytical Methods for Quantifying the Deacetylation Degree in Chitosan Polymer Chains

Chitosan has gained considerable attention in recent years as a versatile material with applications in many fields, including food, pharmaceuticals, tissue engineering, and agriculture. The degree of deacetylation (DD) is a critical parameter of the properties and functionality of chitosan, influencing its solubility, bioactivity and suitability for various applications. Accurate determination of DD is crucial as it directly affects the behavior of the material in different environments. However, high-precision methods for DD measurement are often costly and difficult to access, posing a challenge for both academic research and industrial applications. In this study, we evaluated the DD of commercial chitosan using a variety of widely available techniques, including potentiometric titration (PT), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, UV-Vis spectroscopy, and X-ray diffraction (XRD). Despite observed differences between methods, all techniques effectively quantified DD, shedding light on factors such as sample solubility, moisture content, baseline correction, and instrument accuracy that contribute to these differences. By demonstrating the feasibility and reliability of simple and accessible techniques for DD determination, this study provides valuable insights for improving the use of chitosan in both research and industry, making these materials more accessible for a wide range of applications.