| Summary: | 碩士 === 國立勤益科技大學 === 化工與材料工程系 === 99 === This study develops scaffolds to suit cell seeding for bone regeneration, and technology for magnetic-seeding cell into the scaffolds. The first part is blended the various ratios of biodegradable poly (DL-Lactide/Glycolide), gelatin and Hydroxylapatite to prepare complexes. And the complexes were freeze-dried to produce three-dimensional porous scaffolds, included G0HA100, G33HA67, G50HA50, G67HA33 and G100HA0 scaffolds. Degradation assay of the scaffolds was used to determine the water content and the degradation rate. The scanning electron microscope (SEM) was performed to examine the structure of pores. The dynamic mechanical analyzer (DMA) instruments determined the mechanical properties of the scaffolds. The poly (DL-Lactide/Glycolide) has an excellent biocompatibility and constructs the shape of complex scaffolds. Gelatin can replace the organic compositions in the bone. Over time, the degradation of gelatin enlarges pores of scaffold, which enhances the cell seeding. The Hydroxylapatite has the ability to osteogenesis and osseous integration. After 96 hours in degradation assay, G33HA67 reached the high water content (47.63%) and became moderate. The high water content can promote the cell growth and cell seeding. It also showed G33HA67 has a low degradation rate. G33HA67 presented pore size distribution range from 187 to 315 μm. After 7 days of degradation, the storage modulus of G33HA67 was 0.25 MPa, it was higher than other scaffolds. Based on the above results, the ratio of G33HA67 scaffolds produced the most stable three-dimensional porous structure, and it was the most suitable artificial scaffold for bone regeneration.
The second part was magnetic nanoparticles labeled osteoblask-like cells (MG-63) for magnetic-seeding cell into the previous three-dimensional porous scaffolds to raise the cell density in a scaffold. To evaluate the affect of magnetic nanoparticles on MG-63, the technology of cell labeling with magnetic nanoparticles is established, labeling ratio, magnetic nanoparticles content in cells, and cell morphology is examined by frozen sectioning and staining. According to cell morphology, labeling ratio, cell proliferation and alkaline phosphatase activity analysis, when the concentration of nano-magnetic particles 50 μg/ml shown better results than the concentration of nano-magnetic particles 500 μg/ml. So we consider that 50 μg/ml of nano-magnetic particles is the optimal concentration for cells labeling.
The third part, magnetic nanoparticles labeled MG-63 cells were magnetic-seeded into scaffolds of G33HA67, and then cell distribution was observed by frozen section and fluorescent staining. At 0 minute, no cell was found in the center hole of scaffolds was observed. At 10 minutes, the cells appeared around the center hole of scaffolds. But the cells had begun to migrate into scaffold after 30 minutes. The significant cells migration into scaffold was observed at 60 minutes. Therefore, magnetic nanoparticles labeled osteoblask-like cells were successfully magnetic-seeded into the three-dimensional porous scaffolds. It is an effective method to enhanc the cells dispersed homogenously in scaffolds.
|
|---|
