Effects of processing parameters on morphology and diameter of electrospun gelatin nanofibers

Abstract

Gelatin is a natural biopolymer which has a potential to apply in biomedical field in the near future. Therefore, this research was focused on the preparation of electrospun gelatin nanofibers. Gelatin solutions were prepared in single (acetic acid) and mixed solvent (acetic acid/dimethylsulfoxide; Ac/DMSO, acetic acid/ethylene glycol; Ac/EG, acetic acid/formamide; Ac/F, and acetic acid/trifluoroethanol; Ac/TFE) systems prior to electrospinning. The effects of solution parameters, including gelatin concentration, solvent system and solution properties (e.g. viscosity, surface tension, and conductivity) on appearance of the electrospun webs and diameter of gelatin fibers were examined. The morphological appearance of the as-spun fibers were carefully investigated using scanning electron microscopy. From the results, based on single solvent system, it was found that the average diameter of the as-spun fibers was increased from about 214 nm to about 840nm upon increasing gelatin concentration from 15%w/v to 29%w/v, respectively. Moreover, it was also found that, for the mixed solvent systems, the morphological appearance of the fibers and the electrospun webs depended very much on the properties of the solvents, and hence of the resulting solutions. Particulary, for the gelatin nanofiber electrospun from Ac/DMSO system at various ratios ranging from 97:3 to 91:9, the obtained fibers were smooth without any beads and their diameter were increased with an increase in the amount of DMSO in the mixed solvent.