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Research Subject: One of the important methods in the treatment of skin wounds is the use of wound dressings. Recently, the use of polymer-based wound dressings has become increasingly common. The use of natural polymers is very important in wound dressings. The aim of the present study is to design and manufacture a polyvinyl alcohol/aloe vera wound dressing with the capability of healing skin wounds.
Research Approach: The electrospinning method was applied to prepare the samples. Aloe vera gel was first extracted, purified, and powdered by freeze-drying. In all samples, the amount of polyvinyl alcohol and aloe vera powder was fixed at 8 wt.%. This value was selected empirically based on the quality of the produced fibers. Different samples including different amounts of polyvinyl alcohol and aloe vera were produced and their properties including morphology, tensile strength, swelling, degradability, and antimicrobial properties were investigated.
Main Results: The results showed that the dropless random oriented fibers with uniform diameter were produced. The diameter increased with increasing aloe vera contribution, which was attributed to an increase in viscosity due to the presence of aloe vera. With increasing aloe vera contribution in the samples, tensile strength decreased and the elongation percentage increased. The swelling behavior of the specimens was evaluated by measuring the weight of the specimens in a simulated skin environment and the results showed that the presence of aloe vera increased the hydrophilic properties of the specimens. Antimicrobial activity of the samples against two gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa was investigated using the disk diffusion method and it was found that the presence of Aloe vera in the samples brought antimicrobial activity against Pseudomonas aeruginosa. Finally, the findings of this study confirm the feasibility of using polyvinyl alcohol /aloe vera for the production of the electrospun wound dressing.

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In recent years, significant efforts have been focused on advancements of novel biomaterials based on natural polymers and utilization of efficient methods such as skin tissue engineering for wound treatment. In this study, a 3D printed polycaprolactone (PCL) scaffold coated via immersion in a 1:4 blend of 40% silk fibroin from Bombyx mori cocoons and TEMPO-oxidized was developed. The pore size and the porosity were 180 µm and 85%, respectively. The results demonstrated an enhancement in exudate absorption (swelling and water uptake of 1342% and 80%, respectively), improvement in storage modulus (G’) from 500 to 4000 Pa, as well as viscoelasticity up to 60%, which all are favorable for wound dressing applications. Moreover, the wettability and biodegradability studies revealed an overall increase in contact angle and degradation rate of 19.9°±3, and 95%, respectively. Cell viability and migration studies on fibroblastic cells (L929) using MTT assay, DAPI/ Phalloidin staining, and scratch test showed over 90% viability up to 7 days and complete scratch repair within 24 hours. These findings show that 3D printed PCL scaffolds coated with silk fibroin and oxidized nanocellulose are promising for wound healing applications and might pave the way to natural polymer-based wound dressings.
 

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It is inevitable to replace the tissues and organs that were disrupted due to trauma or various diseases. One of the methods that can help to speed up the regeneration of wounds is to improve the technology of wound dressings. In the current research, by using the properties of polyurethane nanofibers and improving their properties with additives including graphene oxide, selenium nanoparticles, and henna plant extract, it was aimed to improve the performance of wound dressings. After finding the optimal concentration for the electrospinning machine, DMSO solution containing 12 wt.% polyurethane was used to produce wound dressing nanofibers. The images from scanning electron microscope (SEM) confirmed the production of uniform scaffolds composed of polyurethane nanofibers. Antibacterial properties and mechanical properties of the fabric were studied to check the performance of the manufactured fabric as a wound dressing. For the PU-GO-Se-Henna composite sample, the antibacterial activity against two bacteria, S.aureus and E.coli, was 3.26 and 2.85, respectively, which indicates the very attractive antibacterial properties. This sample reached a tensile strength of 92 MPa in the tensile test, which showed a 104% increase in strength compared to the pure polyurethane sample.