The characterization of thin films based on chitosan and tannic acid mixture for potential applications as wound dressings

Natural polymers can be used to produce materials for biomedical application. In this study, polymeric blends based on chitosan and tannic acid in the form of thin films were obtained. They were characterized for the potential application as wound dressings. Thereby, the thermal stability, maximum tensile strength and water vapor permeability were measured. Moreover, the blood compatibility was determined as the erythrocytes hemolysis rate. The results showed that the addition of tannic acid to chitosan improves the physicochemical properties of the film. The maximum tensile strength and water vapor permeation rate were improved. The hemolysis rate was higher for films with a higher amount of tannic acid than for those containing pure chitosan, however, the value was below 5%, which allows for the medical application of the proposed materials as wound dressings.