Extraction, Assembly And Characterization Of Type I Collagen

Collagen is one major structural protein in the extracellular matrix and also one primary component of knot tissues. It accounts for approximately one-third of protein mass in mammal animals and can be found in large quantities in skin, bone, tendon, ligament and blood vessel. With its excellent biocompatibility, biodegradability and weak antigenicity, collagen is widely used in the field of drug delivery and tissue engineering.This thesis used animal skins belonging to different categories as basic raw materials. By using the acid-soluble method, we extracted four animals'type I collagen which were white shark (Carcharodon carcharias), bullfrog (Rana catesbeiana), common quail (Coturnix coturnix) and freshwater herring (Potamalosa richmondia). Using SDS-PAGE to analysis the four kinds of collagen and comparing with standard molecular protein, the result indicated that the peptide chain compositions of the four kinds of collagen were allα1(I)2α2(I), which were identical with that of type I collagen. Surveying the characteristic absorption peak respectively, it showed that they all had the highest characteristic peak at 225±5 nm. It was in accord with the report data. We also measured their concentration with Coomassie Brilliant Blue dyed. The outcome indicated that the extraction rate of white shark was the highest of them and that of quail was the lowest.Making the extracted four kinds of collagen as original liquid, we obtained the corresponding collagen sponge by vacuum freeze-dry. The four collagen sponges were similar in appearance. They had white or faint yellow luster, equable texture and loose structure. We could see many holes with different sizes. Further to measure their physical performance of water content, moist time, soakage and water-absorptivity, the data indicated that collagen sponge had good hydrophile capability and big water-absorptivity. By illuminating shark collagen sponge with the ultraviolet lamp, we hastened the cross-linking of tyrosine and phenylalanine in its collagen molecule, and then obtained the collagen scaffold material with three-dimensional network structure.We designed to prepare collagen hydrogel film with dialysis method. In this way we fabricated saturated white shark and bullfrog collagen into collagen hydrogel film through dialyzing them and...