Core-sheath gelatin based electrospun nanofibers for dual delivery release of biomolecules and therapeutics.

Coaxial electrospinning with the ability to use simultaneously two separate solvents provides a promising strategy for drug delivery. Nevertheless, controlled release of hydrophilic and sensitive therapeutics from slow biodegradable polymers is still challenging. To address this gap, we fabricated core-sheath fibers for dual delivery of lysozyme, as a model protein, and phenytoin sodium as a small therapeutic molecule. The sheath was processed by a gelatin solution while the core fibers were fabricated from an aqueous gelatin/PVA solution. Microstructural studies by transmission and scanning electron microscopy reveal the formation of homogeneous core-sheath nanofibers with an outer and inner diameter of 180 ± 48 nm and 106 ± 30 nm, respectively. Thermal gravimetric analysis determines that the mass loss of the core-sheath fibers fall between the mass loss values of individual sheath and core fibers. Swelling studies indicate higher water absorption of the core-sheath mat compared to the separate sheath and core membranes. In vitro drug release studies in Phosphate Buffered Saline (PBS) determine sustained release of the therapeutics from the core-sheath structure. The release trails three stages including non-Fickian diffusion at the early stage followed by the Fickian diffusion mechanism. The present study shows a useful approach to design core-sheath nanofibrous membranes with controlled and programmable drug release profiles.