Assessing the physical and mechanical properties of poly 3-hydroxybutyrate-chitosan-multi-walled carbon nanotube/silk nano-micro composite scaffold for long-term healing tissue engineering applications

Abstract

The new nano-micro hybrid scaffolds were fabricated through electrospinning the poly 3-hydroxibutyrate-chitosan-multi-walled carbon nanotube (MWNT) nanofibres on the silky knitted microfibers, orderly and randomly. The scaffolds were prepared by varying the concentration of MWNT. The samples were compared as to their alignment and MWNT concentration. The morphological and physical properties were assessed through scanning electron microscopy, Fourier transform infra-red (FT-IR) spectroscopy and water contact angle test. Mechanical properties were determined through tensile strength test run on optimal samples chosen according to the results obtained from above-mentioned tests. The morphological view of the scaffolds showed that an increase in the amount of MWNT up to 1 wt led to a better fibres diameter distribution and alignment in comparison with other samples. The porosity percentage of all scaffolds were >80 which is appropriate for tissue engineering applications. The FT-IR spectra indicated that the nanofibrous coat on knitted silk did not have any effect on crystallinity structures of silk fibroin. There existed a direct relation between hydrophilicity of scaffolds and MWNT concentration according to water contact angle. The presence of nanofibrous coat on knitted silk had no effect on tensile strength increment in comparison with pure knitted silk. The poly 3-hydroxybutyrate-Chitosan-1 wt MWNT/Silk scaffolds could be an appropriate biomimetic for extracellular matrix of long-term healing tissues in order to their tissue engineering applications.