Composite membranes of alginate and chitosan reinforced with cotton or linen fibers incorporating epidermal growth factor.

Suture threads of cotton or linen, in crossed and random orientation, were added to alginate-chitosan membranes intended to wound coatings application to improve the mechanical properties. The elongation at break increased to about 5 and 8 times for membranes with linen and cotton, respectively, both in the crossed orientation. The addition of the threads increased roughness and opacity of the membranes and reduced the liquid absorption capacity and water vapor transmission rate. The lowest toxicity to human fibroblasts was observed for extracts of membranes produced with linen, and incorporation in them of epidermal growth factor was able to slightly increase cell proliferation.

Comparison of the properties of membranes produced with alginate and chitosan from mushroom and from shrimp.

Dense and porous chitosan-alginate membranes (1:1 in mass) useful as coverages of skin wounds treated through cell therapy were produced using chitosan of different chain sizes from fungal (white mushrooms) and animal (shrimp shells) sources. Porous materials were obtained by adding the surfactant Poloxamer 188 to the formulations. The influence of chitosan type on membranes physicochemical properties and toxicity to fibroblasts was evaluated. Porosity was noticed to be more pronounced in membranes obtained with fungal chitosan and increased with its molecular mass. These formulations showed the highest values of thickness, roughness, opacity, liquid uptake and water vapor permeability. The membranes were not toxic to fibroblasts, but the lowest cytotoxicity values (0.16-0.21%) were observed for membranes prepared with fungal chitosan in the presence of surfactant. In conclusion, it is possible to replace chitosan from animal sources by chitosan of fungal origin to produce membranes with negligible cytotoxicity while maintaining appropriate physicochemical properties.