Preparation and evaluation of chitosan-gelatin composite scaffolds modified with chondroitin-6-sulphate

The objective of the present study was to investigate the properties of porous chitosan–gelatin scaffolds. The modification of samples was done by incorporation of chondroitin-6-sulphate in bulk phase through cross linking with glutaraldehyde. Scaffolds were prepared using the freeze-drying method. An in vitro cell culture of fibroblasts L-929 was employed to study the growth and attachment of cells to the scaffolds. Optical microscopy showed high cell density for the sample supplemented with chondroitin-6-sulphate. Scanning electron microscopy was used to analyze the growth and attachment of cells. Results of the tests revealed that the sample with a 65: 35 ratio of gelatin and chitosan was suitable for both cell attachment and proliferation in fibroblast cultures. The cell viability 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) assay with human mesenchymal stem cells on the previous sample showed about 80 % increase in cell viability. To analyze the mechanical properties of scaffolds, the tensile strengths of the samples were measured and all samples showed stress at break above 0.1 MPa. Optimum substratum composition for porous scaffolds would involve a compromise between the desired attributes of biocompatibility, promotion of cell growth and mechanical strength.