High-performance gel-permeation chromatography of chitosan samples

The conformational properties of chitosan, a copolymer of 2-acetamido-2-deoxy- d -glucose and 2-amino-2-deoxy- d -glucose, have been examined both in solution and in the solid state. Little has been reported previously on the determination of molecular weight using high-performance gel-permeation chromatography (HPGPC) and no attempt has been devoted to an examination of molecular weight distribution. An HPGPC method for evaluating the above-mentioned parameters for chitosan samples having different molecular weights and different degrees of acetylation was therefore developed. Calibration using sodium polystyrene sulfonate commercial standards of narrow molecular weight distribution could not be carried out in the solvent system used for chitosan. Calibration was therefore performed by means of chitosan samples obtained by depolymerization.