Fabrication of cyanophycin-chondroitin sulfate porous scaffold

• Main Authors: Ya-Ting Chang, 張雅婷
• Other Authors: Wen-Chi Tseng
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/15550775486406351137

碩士 === 國立臺灣科技大學 === 化學工程系 === 103 === Cyanophycin granule peptide (CGP) is a nonribosomally synthesized polypeptide. The polymer we used is composed of aspartic acid as the backbone, arginine and lysine as the side chain. Chondroitin sulfate, a kind of glycosaminoglycan abundant in the cartilage tissue of human, is a linear polysaccharide consisting of repeating disaccharide units of glucuronic acid and galactosamine, which is commonly sulfated at C-4 and/or C-6 of galactosamine. In this study, we fabricated and characterized different ratios of cyanophycin-chondroitin sulfate(CGP-CS) porous scaffold. First of all, for the preparation of cyanophycin-chondroitin sulfate conjugate, we used 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-Hydroxysuccinimide (NHS) to covalently conjugate the amine groups of lysine residues of cyanophycin and the carboxyl groups of chondroitin sulfate by forming amide bonds. To fabricate the porous CGP-CS scaffold, we prepared different ratios of CGP-CS solution in 24-well plate, then removed water in the scaffolds by freeze-drying method. Glutaraldehyde was used as a cross-linker to preserve a porous scaffold structure, so the color of CGP-CS scaffolds performed orange. With more cyanophycin, the diameter and volume of the CGP-CS scaffold increased. The cross-linking results of different ratios of CGP-CS scaffold were observed by a fluorescent method and a fluorescent microscope. With increasing the amount of cyanophycin, the brightness and area of the green fluorescence also increased. Moreover, the morphology of the surface and the cross section of CGP-CS scaffold were observed by Scanning Electron Microscopy (SEM). The scanning electron micrograph showed that a porous structure was present in all ratios of scaffold with a pore size of 20-100μm at the surface and 30-90μm at the cross section. Furthermore, the water retention of CGP-CS scaffolds in different points was also investigated. The result showed that the water retention of scaffolds was around 1500-2250% after immersing in PBS for 24 hours . In conclusion, all ratios of cyanophycin-chondroitin sulfate scaffold were fabricated with the porous structure at the surface and the cross section, and also had good water-binding capacity. We hoped that the CGP-CS scaffold can become one of the promising biomaterial applying on tissue engineering someday.