New Solvent System for the Fabrication of Polyvinyl Alcohol – Gelatin Nanofibers via Electrospinning

Polyvinyl Alcohol (PVA) is a biocompatible polymer with high mechanical strength used in the biomedical industry. While its features have biological properties, it lacks cell recognition sites that affect the entirety of cell proliferation and movement. To address this issue, gelatin (GEL) is added to the system to increase biomimetic properties. PVA and GEL nanofibers, produced from electrospinning, could provide new characteristics for tissue engineering applications. At present, aqueous solution of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and many other hazardous organic solutions are used in fabricating both PVA, GEL and PVA-GEL nanofibers, but it poses a great threat on sites that the solvent was unable to evaporate, affecting cell viability and motility. In this study, a new solvent system of deionized water, formic acid and glacial acetic acid was used to replace the current toxic solvent system utilized in electrospinning such polymers. Increasing amounts of formic acid and deionized water decreased further the fiber diameter of the PVA-GEL nanofibers. Further refinement in solution (PVA:GEL ratio) and process parameters (tip-to-collector distance and flow rate) produced much finer nanofibers, leading to a decrease in fiber diameter distribution. It is conclusive that a new alternative solvent system can be used in electrospinning PVA-GEL nanofibers that are non-toxic and exhibits much lower fiber diameter (≈20 nm) than the conventional solvents used before.