Preparation and evaluation of poly(ester-urethane) urea/gelatin nanofibers based on different crosslinking strategies for potential applications in vascular tissue engineering

Due to the brittleness of gelatin, the resulting absence of mechanical performance restricts its applications in vascular tissue engineering. In this research, the fabrication of poly(ester-urethane) urea/gelatin (PU75) nanofibers via an electrospinning technique, followed by different crosslinking methods, resulted in the improvement of its mechanical properties. Poly(ester urethane) urea (PEUU) nanofibrous scaffolds and PU75-based nanofibrous scaffolds were characterized using scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, wide-angle X-ray diffraction (WAXRD), a mechanical properties test, a cytocompatibility assay, a hemolysis assay, and a histological analysis. Water contact angle (WCA) tests confirmed that the PU75-GA (PU75 nanofibers crosslinked with glutaraldehyde vapor) nanofibrous scaffold surfaces became more hydrophilic compared with other crosslinked nanofibrous scaffolds. The results show that the PU75-GA nanofibrous scaffold exhibited a combination of excellent mechanical properties, suitable pore diameters, hydrophilic properties, good cytocompatibility, and reliable hemocompatibility. Overall, PU75-GA nanofibers may be a potential scaffold for artificial blood vessel construction.

SEM micrographs of the PEUU nanofibrous membrane, PU75 nanofibrous membrane, PU75-DT nanofibrous membrane, PU75-GA nanofibrous membrane, and PU75-E/N nanofibrous membrane and magnified 1000, 5000, and 10 000 times, respectively.