Fabrication of gelatin nanofibrous scaffolds using ethanol/phosphate buffer saline as a benign solvent

Electrospinning of natural polymer nanofibers useful for biomedical applications often requires the use of cytotoxic organic solvents. In this study, gelatin nanofibers are electrospun from phosphate buffer saline/ethanol binary mixtures as a benign solvent at ambient temperature. The influences of ionic strength, ethanol concentration, and gelatin concentration on the electrospinnability of gelatin solutions and the fiber microarchitectures are analyzed. The electrospun scaffolds retain their morphologies during vapor-phase crosslinking with glutaraldehyde in ethanol and the subsequent removal of salts contained in the nanofibers via water rinsing. When fully hydrated, the mechanically preconditioned scaffolds display a Young's modulus of 25.5 ± 5.3 kPa, tensile strength of 55.5 ± 13.9 kPa, deformability of 160 ± 15%, and resilience of 89.9 ± 1.8%. When cultured on the gelatin scaffolds, 3T3 fibroblasts displayed spindle-like morphology, similar to the cell's normal morphology in a 3D extracellular matrix.