Thermoinduced aggegation of chitosan systems in perikinetic and orthokinetic regimes

Anna Rył; Piotr Owczarz

doi:10.1016/j.carbpol.2020.117377

Thermoinduced aggegation of chitosan systems in perikinetic and orthokinetic regimes

Carbohydr Polym. 2021 Mar 1:255:117377. doi: 10.1016/j.carbpol.2020.117377. Epub 2020 Nov 5.

Authors

Anna Rył¹, Piotr Owczarz²

Affiliations

¹ Department of Chemical Engineering, Lodz University of Technology, 90-924, Lodz, Poland.
² Department of Chemical Engineering, Lodz University of Technology, 90-924, Lodz, Poland. Electronic address: piotr.owczarz@p.lodz.pl.

PMID: 33436208
DOI: 10.1016/j.carbpol.2020.117377

Abstract

Thermoresponsive colloidal chitosan systems forming the polymer structure in situ are an example of promising solutions in tissue engineering as an injectable scaffolds or drug carriers. Their application method, and thus shearing, may affect the aggregation process in accordance with the colloidal engineering approach. The aim of the study is to compare the kinetics of chitosan aggregation in the perikinetic regime (limited by Brownian motions) with the orthokinetic process carried out under the influence of an external shear field. The research was carried out using static multiple light scattering (S-MLS) and rheometric measurement techniques coupled with small-angle light scattering (Rheo-SALS). It has been found that the introduction of an external shear field (orthokinetic regime) accelerates the aggregation of chitosan systems. Simultaneously, the rotational measurements can even lead to spontaneous gelation, most likely caused by changes in the conformation of chitosan molecules, their deformation and ordering along the shear field.

Keywords: Chitosan hydrogels; Colloid aggregation; Rheo-SALS; Thermoinduced gelation.