Poly(glycerol-sebacate)/poly(caprolactone)/graphene nanocomposites for nerve tissue engineering

In this study, mechanical, electrical, physical, and biological properties of polymeric matrixes comprising poly(glycerol-sebacate) (PGS) and poly(caprolactone) (PCL) with various weight ratio of PGS:PCL (1:3 and 1:1) were evaluated in order to apply as nerve guidance conduit. For this purpose, synthetic PGS pre-polymer was acquired using poly-condensation of glycerol and sebacic acid and characterized by attenuated total reflection-fourier transformed infrared (ATR-FTIR) and X-ray diffraction (XRD) spectroscopies. Furthermore, the effect of 1 wt% graphene (Gr) Nano sheets incorporation as filler, was investigated. Blending PGS with PCL significantly improves the hydrophilicity of the samples and improves cells attachment; however, their mechanical properties decreased dramatically. Presence of Gr within the polymeric matrix, significantly increased elastic modulus and tensile strength, which is possibly attributed to its superior mechanical properties and high aspect of ratio. Moreover, aforementioned polymeric matrixes, turned to conductive membranes by addition of Gr, which affected drastically on their biological properties; that way, 3, 4, 5-dimethylthiazol-2, 5-diphenyl tetrazolium bromide assay elucidated that only addition of 1 wt% Gr to the polymeric films resulted in improved cell survival and cell attachment for 7 days of cell seeding. In addition, cell attachment was enhanced considerably by increasing PGS up to 50 wt%, due to positive role of PGS on contact angle reduction. Therefore, the nano-composite film (50PGS-50PCL-1Gr) can be a promising substrate to use as a nerve guidance conduit.