Electrospinning of chitosan/polyvinyl alcohol Pickering emulsion with tea tree essential oil loaded for anti-infection wound dressings

As a natural antibacterial agent, Tea tree oil (TTO) possesses low aqueous solubility. To load TTO in hydrophilic hydroxyethyl chitosan/polyvinyl alcohol nanofiber matrix, Pickering emulsion electrospinning strategy using ZnO/Ag nano composite (ZA) as stabilizer was proposed for anti-infection dressing development. Under the stabilizing assistance of ZA particles in the size range of 53 and 59 nm, Pickering emulsions with homogenously distributed TTO droplets show good stability, which can be further elctrospun into continuously bead-on-string nanofibers under optimized processing conditions. In spite of the volatilization of TTO during electrospinning, the nanofibers possess good and long-term antibacterial activity against both gram-positive and gram-negative bacteria. In vitro experiments indicated that the nanofibers possess superior hemocompatibility and cytocompatibility. Particularly, it can promote the cell proliferation and migration when its concentration is 800 μg/mL or less. In conclusions, Pickering emulsion electrospinning is a feasible strategy for the fabrication of nanofibers loaded with hydrophobic TTO and the as-obtained nanofibers can be potentially applied in infected wounds.