Preparation and properties of silk fibroin/gelatin porous scaffolds for liver tissue engineering

The silk fibroin/gelatin porous scaffold was prepared by the freeze-drying method. The temperature was set as -20°C and -70°C, respectively. The micro-porous morphology was observed by SEM and the porosities were measured. The swelling performance and mechanical property were also investigated. HepG2 cells were cultured in the two kinds of scaffolds to evaluate their biocompatibility. The results show that with decrease of the freezing temperature, the pore size becomes smaller and the porous morphology gets more homogeneous. Reducing freezing temperature results in higher porosity and much stronger mechanical performance. The cell culture results demonstrate that with the decrease of freezing temperature, fewer cells adhere to the scaffold. Cells in scaffolds with higher freezing temperature proliferate gradually. Cells in scaffolds at lower freezing temperature proliferate very well at first, while the proliferation is limited later. It is concluded that the silk fibroin/gelatin porous scaffold can be successfully prepared by the freeze-drying method, and the porous structure and properties of the scaffold can be controlled by adjusting the freezing temperature.