ساخت و ارزيابي خواص فيزيكي- شيميايي غشاي دولايه نانو الياف تهيه‌شده به روش پرينت سه‌بعدي و الكتروريسي، پلي‌كاپرولاكتون- پروپوليس و پلي وينيل الكل/ كيتوزان - دفروكسامين به‌منظور استفاده در التيام زخم

Fabrication and eva‎luation of Physico-Chemical Properties of Bilayer Nanofiber Membrane Polycaprolactone-Propolis and Polycaprolactone / Polyvinylalcohol -Deferoxamine Prepared by 3D Printing and Electrospinning for use in Wound Healing

مهندسي پزشكي

The skin is always exposed to all kinds of damage. Severe skin damage can be life-threatening. An ideal wound dressing should protect the wound from external contamination and facilitate the healing process. However, single-layer wound dressings cannot meet all clinical needs due to their characteristics and shortcomings. Therefore, double-layer wound dressings, which are composed of two layers with different properties, have attracted much attention. In this study, the PCL/PVA solution with the ratio of 12% PCL and 8% PVA was successfully electrospun into a continuous, uniform, beadless nanofibrous scaffold containing 0.2% deferoxamine on a 3D printed layer of PCL containing propolis to form a bilayer wound dressing. The morphology of both components played an important role in the construction of an efficient scaffold used as a wound dressing, due to the high porosity, interconnected pores of the 3D printed PCL, and the suitable specific surface area of the nanofiber membrane, which resulted in the structural similarity of bilayer scaffolds to the ECM while ensuring optimal conditions for cell adhesion, proliferation and differentiation. The preservation of the architectural features of the electrospun and 3D-printed two-component scaffold was confirmed by SEM micrographs, which well highlighted the continuous nanofibrous structure of the electrospun component with diameter of 564±97 nm and the highly porous morphology of the 3D-printed PCL with diameter of 475±154 μm and porosity of 609±97 μm. The studies of the release profiles of the loaded drugs showed that, on the one hand, propolis loading on the 3D printed sample led to a release of the antibacterial drug creating a non-growth halo with a diameter of 12 mm on staphylococcus aureus. On the other hand, the incorporation of defroxamine as a drug in the nanofibrous membrane led to a controlled and sustained release profile of DFO explosively in the first 4 hours (75.31%) and 86.15% cumulatively in 44 hours and increased its bioavailability and therapeutic efficacy. According to quantitative in vitro biological eva‎luation (MTT assay), the two-component 3D-Nanofiber scaffold presented good cytotoxic compatibility and no cytotoxic potential in L929 cell line. The highest level of cell viability and proliferation was observed in the presence of this two-component scaffold after 72 hours of incubation with viability of 145%. The results of the cellular response eva‎luation proved the potential of the two-component scaffold to enhance the adhesion and proliferation of L929 cells and to sustain the regeneration of damaged skin tissue. This wound dressing showed biocompatibility, biodegradability and good mechanical properties. By adding the 3D structure to the nanofibers, the tensile strength increased to 4.3±0.55 and the elastic modulus increased to 31.33±6.79 MPa. In summary, bilayer wound dressing can be a potential candidate for biomedical applications due to its high biocompatibility and significant antibacterial and wound healing activities.

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