Silk fibroin/chitosan scaffold: preparation, characterization, and culture with HepG2 cell

Tissue engineering requires the development of three-dimensional water-stable scaffolds. In this study, silk fibroin/chitosan (SFCS) scaffold was successfully prepared by freeze-drying method. The scaffold is water-stable, only swelling to a limited extent depending on its composition. Fourier Transform Infrared (FTIR) spectra and X-Ray diffraction curves confirmed the different structure of SFCS scaffolds from both chitosan and silk fibroin. The homogeneous porous structure, together with nano-scale compatibility of the two naturally derived polymers, gives rise to the controllable mechanical properties of SFCS scaffolds. By varying the composition, both the compressive modulus and compressive strength of SFCS scaffolds can be controlled. The porosity of SFCS scaffolds is above 95% when the total concentration of silk fibroin and chitosan is below 6 wt%. The pore sizes of the SFCS scaffolds range from 100 microm to 150 microm, which can be regulated by changing the total concentration. MTT assay showed that SFCS scaffolds can promote the proliferation of HepG2 cells (human hepatoma cell line) significantly. All these results make SFCS scaffold a suitable candidate for tissue engineering.