Preparation and characterization of wound healing hydrogel based on fish skin collagen and chitosan cross-linked by dialdehyde starch

Hydrogels due to high water absorption capacity, flexibility, biodegradability properties and also the ability to provide a moist environment, same as native extracellular, are widely used for wound healing applications. Developing multifunctional hydrogels using biomaterial is an emerging approach in this area. Collagen and chitosan are known as excellent biomaterials due to their properties, functionality, and sustainable sources. They also have good biocompatibility and biodegradability, suitable for wound healing hydrogels. In this study, the physicochemical characterization, morphology, and biocompatibility of collagen/chitosan/ dialdehyde starch hydrogel (Col/Ch/DAS) were evaluated. Type I collagen was extracted from silver carp skin by-product. DAS was synthesized by a one-step method of acid hydrolysis and oxidation. Hydrogels were made from collagen (4 % w/v) and chitosan mix (2 % w/v) and added DAS (2 % w/v) (0.5, 1.0 and 1.5 ml) as a cross-linker to enhance the physicochemical behaviors of the hydrogels. Swelling ratio, biodegradation, water vapor transmission rate (WVTR), surface morphology and the interactions between functional groups of polymers used in the hydrogel were evaluated. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test of extracted collagen indicated the presence of two different α-chains in collagen and confirmed type I collagen. The results showed that DAS content significantly affected the swelling ratio and biodegradability of hydrogels (P < 0.05). Col/Ch/Das0.5 hydrogel showed the highest swelling and biodegradability compared to other hydrogels (P < 0.05). Col/Cs/DAS hydrogels showed suitable water vapor transmission for wound dressing. The Fourier transform infrared spectroscopy (FTIR) results showed that covalent bonds formed via acetalization and Schiff base reaction. The results suggested that the prepared hydrogel from silver carp fish skin collagen has excellent potential as a new wound dressing for medical and biomedical applications such as wound healing.