Preparation and Characterization of Silk-Chitosan Composite as a Three-Dimensional Tool for Culturing Osteoblast-Like Cells

The culture and proliferation of osteoblast-like cells has an important role in clinical and research use and bone biology. The results have shown that culturing cells in a three-dimensional tissue-like microenvironment with engineered geometrical properties gives a better effect on cell culture than two-dimensional ones. The aim of the present study was construction and evolution of a three-dimensional scaffold with suitable features for the cultivation of osteoblast-like cells. Silk-chitosan scaffold was prepared via freeze drying method. Scaffolds structure was analyzed using scanning electron microscopy. The mechanical properties of scaffolds were evaluated via measuring the compressive strength and the degradation of them was investigated via incubating the samples in phosphate buffer salin. The cytotoxicity of silk on MG63 cells was assessed using MTT [3- (4،5-dimethylthiazol-2-yl) -2،5-diphenyltetrazolium bromide] assay and cell adhesion was investigated after cell incubation on silk substrate. Scanning electron microscopy data indicated the appropriate porosity and porous structure (pore size: 200. 90 ± 46. 75 μm) on scaffold surface that might improve nutrient transport، transmission of signal and cell penetration into the scaffolds. The results of mechanical properties showed that the scaffold was appropriate for three-dimensional culture of cells and the compressive strength was 0. 6 ± 0. 8 MPa at scaffold. Degradation test results showed that increasing the weight ratio of the chitosan raised the rate of the scaffold degradation. The results of MTT assay and cell culturing confirmed non-toxicity of silk and its ability to accommodate cell adhesion. Silk-chitosan scaffold prepared via freeze drying methods can be promising for three-dimensional culture of osteoblast-like cells.