Wound care, including wound dressings, is a fast evolving field of science. New approaches to wound care strive to non-invasive, effective techniques and materials that assure adequate wound protection and provide a suitable microenvironment that enables fast healing. Dressings based on nanofibers have such properties, moreover, they are similar in structure to the elements of extracellular matrix, which is favourable for materials used for wound healing. In this master thesis, we focused on the production of biocompatible water-stable nanofibers based on alginate or chitosan in combination with polyethylene oxide, which were prepared by the electrospinning. The aim was to determine how the concentration of individual polymers in the solution affects the process parameters in electrospinning and the morphological properties of nanofibers. The latter was evaluated by light and scanning electron microscopy. Results show that solutions of chitosan with the addition of polyethylene oxide are less processable than solutions of sodium alginate with the addition of polyethylene oxide. Nanofibers, morphologically suitable for wound application, were prepared from a more concentrated alginate-based polymer solutions (4.5%) than from solutions with chitosan (3.5%). The processability also depended on the molecular weight of the polyethylene oxide used. Among the investigated ones (400 kDa, 900 kDa and 2000 kDa) polyethylene oxide 2000 kDa was the most appropriate. We have investigated also the impact of nanofiber composition on its stability in water by immersing microscope slides with electrospun samples of nanofibers in water filled petri dishes. The samples were then analysed under a light microscope. Nanofibers from the chitosan-polyethylene oxide mixtures were more stable in aqueous environment than those prepared from the sodium alginate-polyethylene oxide mixtures. The method for determining the stability of nanofibers in water was shown not to be adequate for evaluation of fiber morphology after exposure to aqueous medium and therefore it needs to be modified or further developed.
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