Development of eudragit electrospun fibers functionalized by cinnamon leaf oil complexation with cyclodextrins for wound healing application

Essential oils are powerful agents which have natural antimicrobial activity. However, its poor water solubility and high volatility make its usage limited. There are different methods to overcome this challenge. Among the most interesting of them is their encapsulation inside nanomaterials which not only could improve their water solubility but also extend the shelf life of essential oils. The aim of this thesis was to reach to a high-performance encapsulated oil via utilizing inclusion complexes and electrospinning methods, simultaneously, to benefit from the advantages of both methods. To reach this aim, Eudragit electrospun fibers were functionalized by cinnamon leaf oil complexation with cyclodextrins. For this, firstly, cinnamon leaf oil was molecularly encapsulated within β-cyclodextrin and sulfobutyl ether β-cyclodextrin sodium via freeze-drying method. Solubilizing and complexing ability of β-CD and SBE-β-CD were confirmed via phase solubility assay. Encapsulated amount of CEO was determined using UV-Vis spectrometry. The formation of inclusion complexes was characterized by several analyses includes DLS, SEM, FTIR, TGA, DSC, and 1H-NMR spectroscopy. Then, the antibacterial activity of CEO/β-CD-IC and CEO/SBE-β-CD-IC were assessed against both gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus). In the second part, CEO/βCD-IC loaded Eudragit S100 fiber and CEO/SBE-βCD-IC loaded Eudragit S100 fiber were produced using the electrospinning method, and the physicochemical properties, wetting ability, and water uptake capacity of the electrospun fibers were characterized. The antibacterial activity of these fibers was determined against E. coli and S. aureus by the colony counting method. Also, the cytotoxic effect of these fibers was tested on the L929 fibroblast cell line. The amount of oil inside the fibers and their release profile at different pH were determined by UV-Vis spectrometry. According to the results of this study, CEO/βCD-IC loaded Eudragit S100 fiber was found to be a good candidate for wound healing applications especially for treatment of diabetic ulcer because of its high-water uptake, a balanced hydrophilic outer surface, non-toxic property, high antibacterial activity, and controlled drug release ability at pH 5.5.