Design and fabrication of poly (glycerol sebacate)-based fibers for neural tissue engineering: Synthesis, electrospinning, and characterization

Poly (glycerol sebacate) (PGS) is a thermoset biodegradable elastomer considered as a promising candidate material for nerve applications. However, PGS synthesis is very time and energy consuming. In this study, the PGS pre-polymer (pPGS) was synthesized using three synthesis times of 3, 5, and 7 hours at 170 degrees C. Fourier transform infrared (FTIR), nuclear magnetic resonance spectroscopy, X-ray diffraction analysis, and differential scanning calorimetry thermogram were utilized to study the pPGS behavior. Poly (vinyl alcohol) was used as a carrier to fabricate aligned poly (vinyl alcohol)-poly (glycerol sebacate) (PVA-PGS) fibers with various ratios (60:40, 50:50, and 40:60) using electrospinning and crosslinked through the thermal crosslinking method. Morphology of the fibers was studied before and after crosslinking using scanning electron microscopy (SEM). FTIR, mechanical properties in the dry and wet state, water contact angle, in vitro degradation, and water uptake behavior of crosslinked scaffolds were also investigated. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, SEM analysis, and 4 ', 6-diamidino-2-phenylindole (DAPI) staining were utilized to determine the biocompatibility of scaffolds. The results show the synthesized pPGS in 3 hours at 170 degrees C is the optimized sample in the terms of chemical reaction. All scaffolds have bead-free and a uniform fiber diameter. The Young's modulus of crosslinked PVA-PGS (50:50 and 40:60) fibers is shown to be in the expected range for nerve applications. The cell culture studies reveal PVA-PGS (50:50 and 40:60) fibers could lead to better cell adhesion and proliferation. The results suggest that PVA-PGS (50:50 and 40:60) is a suitable and promising biodegradable material in the fabrication of scaffolds for nerve regeneration.