N-isopropyl chitosan. A pH- and thermo-responsive polysaccharide for gel formation

Michela Cok; Marco Viola; Federica Vecchies; Pasquale Sacco; Franco Furlani; Eleonora Marsich; Ivan Donati

doi:10.1016/j.carbpol.2019.115641

N-isopropyl chitosan. A pH- and thermo-responsive polysaccharide for gel formation

Carbohydr Polym. 2020 Feb 15:230:115641. doi: 10.1016/j.carbpol.2019.115641. Epub 2019 Nov 19.

Authors

Michela Cok¹, Marco Viola¹, Federica Vecchies¹, Pasquale Sacco¹, Franco Furlani¹, Eleonora Marsich², Ivan Donati³

Affiliations

¹ Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, 34127 Trieste, Italy.
² Department of Medical, Surgical and Health Sciences, University of Trieste, Piazza dell'Ospitale, 34127 Trieste, Italy.
³ Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, 34127 Trieste, Italy. Electronic address: idonati@units.it.

PMID: 31887884
DOI: 10.1016/j.carbpol.2019.115641

Abstract

The present contribution deals with the synthesis and characterization of N-isopropyl chitosan in which the introduction of hydrophobic groups leads to an increased flexibility of the polysaccharide backbone. The isopropyl groups extend the solubility of the modified-chitosan samples and render the modified chitosan a pH- and thermo-sensitive system for hydrogel formation. Indeed, upon varying the pH of the system and/or its temperature within a range compatible with biological applications, a non-reversible sol-gel transition occurs, as determined through extended rheological analyses. The modified chitosan samples show a very good biocompatibility as determined through preliminary viability and cell growth experiments.

Keywords: Hydrogel formation; N-isopropyl modified chitosan; Rheology; Thermal stimulus; pH-stimulus.