Emulsion-coaxial electrospinning: The role of zein as a shell layer in multicore-shell structured nanofibers for bioactive delivery

Multicore-shell nanofibers were fabricated by integrating emulsion electrospinning and coaxial electrospinning technologies, in which the multicore section of the nanofibers was prepared by electrospinning of gelatin- stabilized emulsions, and the shell layer was coaxially electrospun from zein solution. Coaxial electrospinning of zein helped form emulsion-based electrospun fibers with bead-in-string, spindle-like, and straight morphologies. The hydrogen bonding between gelatin and zein contributed to the enhanced thermal properties of coaxially electrospun nanofibers. The coating of zein as shell greatly improved fiber surface wettability and mechanical strength. The release behavior of curcumin from the nanofibers was dominated by Fickian diffusion, and the zein shell as a physical barrier favored the prolonged release of curcumin and then the long-lasting antibacterial activity towards Escherichia coli. This work thus gives an insight into the development of the nanofibers by emulsion-coaxial electrospinning as encapsulation matrices for the application in food products.