title: Separation of chitosan by degree of acetylation using simple free solution capillary electrophoresis.
abstract: Chitosan is a biopolymer of increasing significance, as well as a renewable and sustainable material. Its main molecular characteristics are molar mass and degree of acetylation (composition). Precise average degrees of acetylation were measured by quantitative (1)H solution-state NMR spectroscopy. While number-average degrees of acetylation had already been determined by (1)H NMR spectroscopy, weight-average degrees of acetylation are also determined and may be more relevant for some properties, such as mechanical properties. We report the first separation of chitosan according to its degree of acetylation using free solution capillary electrophoresis. Capillary electrophoresis separates chitosan in the 'critical conditions': the molar mass plays little role and the separation is by the degree of acetylation. It characterises the heterogeneity of chitosan samples in terms of composition (dispersity of the distribution of degrees of acetylation). This heterogeneity (broad distribution of degrees of acetylation) cannot be neglected contrary to a common assumption found in the literature. This fast and easy separation will allow establishing a structure-property relationships.
authors.affiliation: Australian Centre for Research on Separation Science (ACROSS), School of Science and Health, University of Western Sydney, Parramatta, Locked Bag 1797, Penrith, NSW, 2751, Australia.
authors.forename: Mariam
authors.initials: M
authors.lastname: Mnatsakanyan
authors.forename: Joel J
authors.initials: JJ
authors.lastname: Thevarajah
authors.forename: Rozet Sallom
authors.initials: RS
authors.lastname: Roi
authors.forename: Antonio
authors.initials: A
authors.lastname: Lauto
authors.forename: Marianne
authors.initials: M
authors.lastname: Gaborieau
authors.forename: Patrice
authors.initials: P
authors.lastname: Castignolles
mesh_terms: D000107:Acetylation; D048271:Chitosan / Q000737:chemistry* / Q000302:isolation & purification*; D019075:Electrophoresis, Capillary / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011522:Protons
chemical_list: D011522:Protons; D048271:Chitosan