Impact of polyampholyte macromolecular structure on the conformation of chitosan derivatives
Abstract
Chitosan is a biocompatible and bioresorbable polymer family whose primary amine groups allow easy chemical modification through re-acetylation or functionalization, producing derivatives with tailored properties. While many chitosan derivatives have been characterized, detailed studies of ampholytic chitosan derivatives remain limited. This study investigates how the macromolecular structure of modified chitosans influences their physicochemical properties. The work focuses on chitosan functionalized with chelating ligands: polycarboxylates (DOTAGA, DTPA, EDTA) and the octadentate ligand DFO. Using several analytical techniques, the study examines the relationship between these structural modifications and resulting physicochemical behavior. A key contribution is a charge-based classification derived from two parameters: the mean charge of the repeat unit (c̅) and the charge fluctuation between adjacent units (δc 2 ). Based on charge fluctuation, chitosan derivatives are categorized into three groups: cationic derivatives (δc 2 < 0.5), weak polyampholytes (0.5 < δc 2 < 1.5), and strong polyampholytes (δc 2 > 1.5). This classification correlates strongly with measured properties such as isoelectric point, Newtonian viscosity, and polymer conformation in solution, including gyration and hydrodynamic radii at high ionic strength and polyelectrolyte peak behavior at low ionic strength. The results demonstrate that charge distribution is a key determinant of the solution behavior and physicochemical properties of chitosan derivatives.
Related
- Towards tunable mechanical properties of in situ gelling chitosan hydrogels: impact of macromolecular structure including pattern of acetylation
- The stage-wise macromolecular assembly and structure evolution of silk along the silk gland
- Toward a New Paradigm for Renewable Biopolymer Selection: A Structure–Processing–Architecture–Property–Scalability Framework (Alginate, Cellulose, Lignin, Chitosan, and Starch)
- Structure–property relationships in a graphene oxide-reinforced chitosan–carboxymethylcellulose–alginate composite for wound dressing applications
- Effect of ChCl:Glycolic Acid Molar Ratio and Plant Extract Incorporation on the Structure–Property Relationships of Chitosan Active Packaging Films
BibTeX
@article{howard2026impact,
title = {{Impact of polyampholyte macromolecular structure on the conformation of chitosan derivatives}},
author = {Jordyn Ann Howard and Juan Felipe Salazar Ariza and Agnès Crépet and Alexander Zaderko and Catherine Ladavière and Fernande da Cruz-Boisson and François Lux and Olivier Tillement and Laurent David},
journal = {Carbohydrate Polymers},
year = {2026},
month = nov,
doi = {10.1016/j.carbpol.2026.125229},
url = {https://hal.science/hal-05852611v1},
note = {CC BY},
}
RIS
TY - JOUR
TI - Impact of polyampholyte macromolecular structure on the conformation of chitosan derivatives
AU - Jordyn Ann Howard
AU - Juan Felipe Salazar Ariza
AU - Agnès Crépet
AU - Alexander Zaderko
AU - Catherine Ladavière
AU - Fernande da Cruz-Boisson
AU - François Lux
AU - Olivier Tillement
AU - Laurent David
PY - 2026
DA - 2026/11/04
JO - Carbohydrate Polymers
DO - 10.1016/j.carbpol.2026.125229
UR - https://hal.science/hal-05852611v1
AB - Chitosan is a biocompatible and bioresorbable polymer family whose primary amine groups allow easy chemical modification through re-acetylation or functionalization, producing derivatives with tailored properties. While many chitosan derivatives have been characterized, detailed studies of ampholytic chitosan derivatives remain limited. This study investigates how the macromolecular structure of modified chitosans influences their physicochemical properties. The work focuses on chitosan functionalized with chelating ligands: polycarboxylates (DOTAGA, DTPA, EDTA) and the octadentate ligand DFO. Using several analytical techniques, the study examines the relationship between these structural modifications and resulting physicochemical behavior. A key contribution is a charge-based classification derived from two parameters: the mean charge of the repeat unit (c̅) and the charge fluctuation between adjacent units (δc 2 ). Based on charge fluctuation, chitosan derivatives are categorized into three groups: cationic derivatives (δc 2 < 0.5), weak polyampholytes (0.5 < δc 2 < 1.5), and strong polyampholytes (δc 2 > 1.5). This classification correlates strongly with measured properties such as isoelectric point, Newtonian viscosity, and polymer conformation in solution, including gyration and hydrodynamic radii at high ionic strength and polyelectrolyte peak behavior at low ionic strength. The results demonstrate that charge distribution is a key determinant of the solution behavior and physicochemical properties of chitosan derivatives.
SN - 0144-8617
SN - 1879-1344
ER -