In situ UV-crosslinking gelatin electrospun fibers for tissue engineering applications

Electrospun fibers of natural polymers are desirable for biomedical applications such as tissue engineering. Crosslinking of electrospun fibers of natural polymers is needed to prevent dissolution in water and to enhance mechanical strength. In this study, an in situ UV-crosslinking method was developed for crosslinking of gelatin electrospun fibers (GESFs) and water-soluble synthetic polymers. A mixture of gelatin and phenylazide-conjugated poly(acrylic acids) was electrospun under UV irradiation. The UV-crosslinked GESFs were not dissolved in water with improved mechanical strength. Compared to traditional crosslinking by glutaraldehyde vapor, the GESFs crosslinked by our method are superior in terms of retention of GESF morphology, uniform crosslinking throughout the fibers, low cytotoxic and retention of biofunctionality. L929 cells grew better on the UV-crosslinked GESF scaffolds compared to glutaraldehyde-crosslinked ones. Furthermore, bioactive nanoparticles, e.g. hydroxyapatite, could be incorporated into GESFs for enhancing osteoconductivity, which possess a great potential in bone tissue engineering.