Abstract:
The paper aimed to prepare imino-chitosan fibers by the imination reaction in a heterogenous system, targeting the
improvement of anti-pathogenic activity. To this end, porous neat chitosan fibers were prepared by electrospinning of
the polyethylene glycol/chitosan blend, followed by polyethylene glycol removal. Imination of the neat chitosan fibers
was carried out in three liquid phase systems using solvents of different polarity and, consequently, different ability to
swell the solid phase chitosan fibers. The successful imination was qualitatively and quantitatively assessed by FTIR
and 1H-NMR spectroscopy, and the impact of the liquid phase on the fibers’ morphology was evaluated by SEM, POM
and AFM microscopy. Further, the antimicrobial activity of the imino-chitosan fibers was investigated on relevant
bacterial and fungal strains. It was concluded that the prior swelling in water of the fibers improved the imination
degree, while the use of a less polar solvent, such as toluene, favored the preservation of the fibrous morphology. The
imination with an antimicrobial aldehyde endowed the chitosan fibers with the ability to create a physical barrier
against pathogens.
