Study on modification of collagen with chondroitin sulfate on the microcosmic level

To observe the changes during the process of modificating collagen with chondroitin sulfate (CS), a series of experiments was designed. Collagen scaffold was constructed by lyophilization. CS was attached into the scaffold through crosslinking. Solid-liquid phase separation method was used to shape 3D porous structure. Both kinds of scaffolds were investigated by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Electron Spectroscopy for Chemical Analysis (ESCA), Amino Acid Analyses (AAA), and so on for structures and characteristics. The results showed that CS could improve the properties of collagen both in biocompatibility and mechanical property. It increased the polar groups on the surface of scaffold and protected amino acid residues of collagen fiber. At the same time, the structure of scaffold became more regular because of the increase of polar groups. It was indicated that those were the real reasons for the improvement of modification.