Electrospun nanofibers comprising of silk fibroin/gelatin for drug delivery applications: Thyme essential oil and doxycycline monohydrate release study.

In this study, a nanofibrous electrospun substrate based on the silk fibroin (SF) and gelatin (GT) polymers were prepared and evaluated. The SF/GT blended solutions were prepared with various ratios of GT in formic acid and electrospun to obtain bead-free fibers. Results showed that addition of GT to SF increased nanofiber's diameter, bulk hydrophilicity, surface wettability, mass loss percentage, but decreased Young's modulus, tensile strength, and porosity of the SF/GT mats. According to the obtained results, the mat containing 10% of GT was selected as the optimized mat for further studies and loaded with thyme essential oil (TEO) and doxycycline monohydrate (DCMH) as the antibacterial agents. Release studies showed a burst release of TEO from the mat within the first 3 h, while the DCMH had a sustained release during 48 h. In comparison to the TEO-loaded mat, the DCMH-loaded one showed larger inhibition zones against Staphylococcus aureus and Klebsiella pneumoniae bacteria. Meanwhile, cellular studies using mouse fibroblast L929 cells showed excellent cell-compatibility of TEO- and DCMH-loaded mats.