Diclofenac sodium loaded multi-layered wound dressing for diabetic foot ulcer

Abstract

Diabetic foot ulcer (DFU) is the most important complication of diabetes that is caused by neuropathic and/or peripheral artery disease. New generation wound dressings not only protect wounds from external disturbance but also accelerate wound healing by improving cell proliferation and mimicking the natural extracellular matrix (ECM) of the skin. Electrospinning is one of the most common techniques used in tissue engineering applications to produce nano/micro-scaled fibers, with a high surface to volume ratio, and high drug-loading capacity. In this study, our aim is to fabricate multi-layered Diclofenac Sodium (DS) loaded electrospun Polyvinyl alcohol (PVA) and Poly-e-caprolactone (PCL) fibers, which would provide an effective and prolonged release of DS for the treatment of DFU. DS-loaded multi-layered fibers were fabricated efficiently and characterized by contact angle measurements, FT-IR, mechanical properties, AFM, SEM, and degradation studies. In vitro, drug release tests were also performed at two different temperatures (25°C and 37°C) and pH (5 and 7.4) conditions. The results of contact angle measurement showed that PVA has successfully provided a hydrophilic property to the multi-layered fiber scaffold. According to the SEM images, the multi-layered fibers have a bead-free and uniform structure with a fiber diameter of 1.272 ± 761.04 ìm. The obtained AFM results showed that the multi-layered electrospun fibers have a rough surface area of 1.29 µm, which has a strong correlation for a hydrophilic scaffold for tissue engineering. The data collected from in vitro degradation studies showed that the multi-layered fibers only lost 13.4% of their mass during a 2-week period, proving that the dressing can be applied for more than two weeks without a need for replacement. According to in vitro drug release studies, it was found that the release of DS from electrospun fibers was pH-dependent and a higher amount of drug release was observed at pH 7.4 than at pH 5, which would be an advantageous property for DFU treatment. The results obtained from the characterization studies implied that the fabricated DS-loaded multi-layered electrospun scaffold could be an excellent candidate for wound dressing applications in DFU due to its ability to absorb exudates and high amounts of drug release during the inflammation phase of the wound healing process. In conclusion, the results of this study suggest a promising novel approach for the treatment of DFU. © (2021) Society for Biomaterials & Artificial Organs.