New Synthetic Routes, Wound Healing and Hemostatic Properties of N-Guanidinium Chitosan
Аннотация
The development of novel multifunctional biomaterials remains one of the most pressing challenges in modern materials science. Polymer derivatives of guanidine are in high demand due to their broad spectrum of pharmacological activities. In recent years, various methods have been developed to introduce guanidine groups into the chitosan structure. However, most of the known guanidination methods are carried out in the presence of acids, which leads to the formation of side reactions in the reaction medium. In this study, we present a method for guanidination of chitosan in an aprotic solvent medium - acetonitrile. It has been demonstrated that by varying the molar ratio of the guanidinating reagent, it is possible to obtain N-guanidinium chitosan derivatives with a degree of substitution ranging from 0.16 to 0.45. Notably, the use of acetonitrile prevents hydrolysis of the chitosan macromolecular backbone, and an increase in the number of guanidine groups leads to an increase in the molecular weight of the synthesized N-guanidinium chitosan derivatives. The structure and properties of the obtained chitosan derivatives were confirmed by physico-chemical methods (elemental analysis, FTIR, NMR, XRD, SEM, DLS, etc.). The presence of guanidine groups in the chitosan structure conferred broad pH-range solubility to the synthesized compounds. Results from a comparative in vivo analysis demonstrated that 0.5% solutions of N-guanidinium chitosan exhibited excellent wound healing properties, attributed to the synergistic interaction between the polysaccharide backbone and the guanidine moieties. Pharmacological evaluations confirmed that the introduction of guanidine groups into the chitosan structure enhances its hemostatic efficacy compared to native chitosan. HIGHLIGHTS This study chitosan was subjected to guanylation in an aprotic solvent medium. Guanylated chitosan derivatives with diverse physico-chemical properties and solubility across a broad pH range were synthesized. The N-guanidinium chitosan samples demonstrated effective wound-healing and hemostatic properties. Findings suggest indicate the potential for developing new multifunctional polymeric materials based on chitosan. GRAPHICAL ABSTRACT