Crosslinking of the electrospun gelatin nanofibers

Gelatin (Gt) nanofibers have been prepared by using an electrospinning process in a previous study. In order to improve their water-resistant ability and thermomechnical performance for potential biomedical applications, in this article, the electrospun gelatin nanofibers were crosslinked with saturated glutaraldehyde (GTA) vapor at room temperature. An exposure of this nanofibrous material in the GTA vapor for 3 days generated a crosslinking extent sufficient to preserve the fibrous morphology tested by soaking in 37 °C warm water. On the other hand, the crosslinking also led to improved thermostability and substantial enhancement in mechanical properties. The denaturation temperature corresponding to the helix to coil transition of the air-dried samples increased by about 11 °C and the tensile strength and modulus were nearly 10 times higher than those of the as-electrospun gelatin fibers. Furthermore, cytotoxicity was evaluated based on a cell proliferation study by culturing human dermal fibroblasts (HDFs) on the crosslinked gelatin fibrous scaffolds for 1, 3, 5 and 7 days. It was found cell expansion took place and almost linearly increased during the course of whole period of the cell culture. The initial inhibition of cell expansion on the crosslinked gelatin fibrous substrate suggested some cytotoxic effect of the residual GTA on the cells.