Investigation of the wound dressing material potential of cross- linked alginate-based hydrogels obtained from cocoons of bombyx mori (L., 1758)

In the fields of tissue engineering and regenerative medicine, the need for highly biocompatible materials is increasing, and in this context, natural polymer-based hydrogels stand out with their biomimetic and tissue integrity-supporting properties. Silk sericin protein, a natural polymer obtained from the cocoon of Bombyx mori (L., 1758) silkworm, has the potential to be used as a wound dressing material due to its high biocompatibility, antibacterial, moisture-retaining, and elastic properties, and its easy adaptation to the body. In this thesis, alginate (Alg)-based hydrogels, a natural polysaccharide with good biocompatibility, easy biodegradability, and gel-forming ability, were developed by integrating them with silk sericin protein synthesized from Bombyx mori cocoons, and their use as wound dressing materials in skin tissue was aimed. In addition, Alg-Ser-ZnO hydrogels, developed by loading them with zinc oxide (ZnO) nanoparticles to enhance their antimicrobial properties, were investigated for the first time as wound dressing materials. Hydrogels were characterized by morphological, chemical, and biological analyses (in-vitro swelling behavior, antibacterial activity, biocompatibility, and wound healing). Hydrogels modified with glycerol additive to impart elasticity were developed with the potential to be a functional wound dressing material with antibacterial performance and effective wound healing processes. The developed composite hydrogels have a cross-linked porous morphology and a total porosity of 90-95%. While the hydrogels showed swelling of 200%, the addition of ZnO slightly reduced the amount of swelling and increased the stability of the samples. ZnO loaded hydrogels (Alg-Ser-ZnO) formed an inhibitory zone of approximately 8-10 mm against Staphylococcus aureus and Escherichia coli bacteria in the disk diffusion method. It was observed that Alg-Ser hydrogels significantly supported fibroblast viability and migration, while ZnO loading resulted in dose-time dependent cytotoxicity and migration suppression as the concentration increased. Keywords: Bombyx mori cocoon, Biomaterials, Silk, Sericin, Wound dressing.