ElectrospunPGS/PCLnanofibers: From straight to sponge andspring-likemorphology

Poly(glycerol sebacate) (PGS) is an attractive polymer that has many applications in medical fields, especially in tissue engineering. In this study, the influence of solvent system on electrospinnability, forming of bead-free nanofibers and the morphology of PGS nanofibers was investigated and discussed. Among different solvents, the acidic solvent as a benign solvent was used for electrospinning. The steps were as follows: (a) Synthesis the PGS pre-polymer and analysis its chemical structure by Fourier-transform infrared spectroscopy (FTIR); (b) Electrospinning of the PGS by mixing PCL in eight different solvent systems; (c) evaluation the morphology of produced nanofibers using the scanning electron microscope (SEM); (d) the study of biocompatibility of produced nanofibers by MTT assay. The average diameter of nanofibers in different solvent systems turned out to vary from 260 +/- 63 to 4588 +/- 970 nm and nanofibers with different morphologies were produced by changing the solvent system. Among the produced straight nanofibers, the best samples were FA(30,15)(formic acid), FA/AC(30,15)(formic acid/Acetone), FA/AA(30,15)(formic acid/acetic acid), CF/DMF20,15(chloroform/N,N-dimethylformamide), FA/AA(35,15), and CF/DMF23,15, respectively (based on size and morphology). Also, the produced nanofibers in CF/ET (chloroform/ethanol) had a rough surface. When AA was used as solvent and polymer concentration was kept 35% w/v, sponge-like scaffold was produced. Moreover, spring-like nanofibers were fabricated by using DMF, (at 30% w/v) and AC (in all polymer concentrations). MTT results also demonstrated that CF/DMF(20,15)as produced sample via hazardous solvents (class 3) is biocompatible. These scaffolds can be used in different tissue engineering applications according to their morphology.