Abstract Disturbance in the structure and normal function of the skin and the underlying tissue of the skin leads to the formation of wounds. In other words, this condition is a kind of damage on the surface of the skin, so skin wounds are caused when the cohesion of the skin layers (epidermis, dermis, and subcutaneous tissue) or subcutaneous tissue breaks down. The wounds are different based on depth and size. Acute and chronic wounds are divided into two groups. Skin ulcers that do not heal, that heal very slowly, or heal but keep coming back, are known as chronic ulcers. Most of these chronic skin wounds are caused by burns, skin cancer, infection or diseases such as diabetes and EB wounds. These types of wounds, which are slow to heal, must be under special care. In the current research, an attempt has been made to speed up skin tissue repair, maintain wound moisture, absorb wound secretions, and prevent wound infection in patients with two different ratios of 30 to 70 and 50 to 50 by making fibroin/flax hydrogel dressings to help EB, diabetic and burn wounds healing. For this purpose, first copper nanoparticles were prepared by chemical reduction method, then fibroin was prepared by thermochemical method from silkworm cocoon and flax emulsion from flax plant by extraction method. Fibroin/flax hydrogel dressings were made with two different ratios of 30 to 70 (30SF/70FL) and 50 to 50 (50SF/50FL). Also, in order to prevent wound infection, hydrogel dressings containing 5%wt of copper nanoparticles were prepared. In addition, hydrogel dressings containing 0.0001g of curcumin were made to accelerate the healing of EB, diabetic and burn wounds. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to confirm the desired phases and to investigate chemical functional groups in hydrogel wound dressings, respectively. Young's modulus and tensile strength of fabricated nanocomposites were eva‎luated as indicators of mechanical properties. Also, biodegradability tests, pH changes, water absorption, curcumin release, antibacterial activity, fibroblast cell survival percentage, cell growth, and proliferation were conducted in order to closely examine the biological properties of hydrogel nanocomposites. The elemental analysis map was used to investigate copper nanoparticles in hydrogel wound dressings, which confirmed the presence of copper nanoparticles. The obtained results showed that the flax has electronegative properties, which is the reason for increasing the strength. Also, the combination of fibroin and flax with each other causes the creation of hydrogen bonds in hydrogel wound dressings, and the increase in the ratio of flax to fibroin has led to an increase in hydroxyl functional groups, which increases the tensile strength of 30SF/70FL hydrogel wound dressing by about 3 times and is equal to 13.1672 MPa. Also, more hydrogen bonds were created between the hydrogel layer and the substrate, and the interface of fibroin/flax hydrogel wound dressings with a ratio of 30 to 70 was not observed. The release of curcumin in fibroin/flax/curcumin wound dressings compared to fibroin/flax/curcumin/copper nanoparticle wound dressings, due to its lower molecular weight, was higher and within 50 minutes. The survival percentage of fibroblast cells on hydrogel wound dressings was more than 80% after 5 days. 30SF/70FL/Cu, 30SF/70FL/Cu/Cur, 50SF/50FL/Cu/Cur and 50SF/50FL/Cur wound dressings had antibacterial properties and prevented infection due to the presence of copper nanoparticles. In addition to preventing infection, hydrogel wound dressings also helped to repair the skin tissue faster.

نرگس جوهري

علي صمدي كوچكسرايي

مرتضي هادي