- 學位論文
利用Osteopontin-motif peptide塗層於生醫材料表面上以促進骨細胞貼附
Osteopontin-motif-peptide Coated Biomaterials Stimulate Bone Cell Adhesion
摘要
鈦及鈦合金具有較佳的彈性模數和良好的耐蝕性，因此廣泛地應用於生醫材料中。然而，鈦金屬對組織的相容性不足於生物活性陶瓷，如羥基磷灰石和生物活性玻璃等，因此近年來學者均利用表面改質的方法促進鈦金屬的生物相容性。許多研究表示，材料表面的生化反應會影響植體植入骨頭的生長情況。為此提出一仿生改質技術；將位於細胞膜外基質的一小段胜肽(Arginine-Glycine-Aspartic acid，RGD)固定於材料上以促進細胞貼附。先前的研究顯示RGD胜肽序列相當穩定，且可以利用化學合成方法獲得高純度的化學成分。因此本研究提出將含有RGD的骨橋蛋白(osteopontin-motif peptide, OMP)固定在鈦金屬表面，俾利於骨細胞的增生與貼附。 利用蛋白質純化方法得到OMP胜肽後，透過化學處理方式使鈦金屬表面與OMP胜肽產生共價結合。經傅立葉轉換紅外線光譜分析儀(FTIR) 與掃描式電子顯微鏡(SEM)鑑定鈦金屬上已接枝OMP胜肽及材料表面形態差異。細胞與試片共培養，透過SEM觀察和WST-1分析其細胞貼附之形態與活性。 FTIR分析鈦金屬表面顯示有接枝OMP胜肽的波鋒，進一步以細胞培養與活性分析顯示，骨母細胞在有接枝OMP胜肽鈦金屬表面之培養條件下，細胞貼附數目較多，型態也較為平坦且伸展。 綜合目前研究結果顯示，本實驗合成之OMP胜肽可增進與細胞之貼附能力；進而能應用於生醫材料工程，提升其生物相容性。
並列摘要
Titanium and its alloys have been extensively used as biomaterials in bone surgery due to its relatively low modulus and superior corrosion resistance. However, its biocompatibility remains inferior to other biomaterials such as ceramics and bioactive glasses. To overcome this obstacle, the researchers have modified the surface of titanium in order to successfully facilitate cell adhesion. A number of studies have shown that surface biochemistry of materials is known to influence the bone in growth of an implant. One approach for biomimetic surface modification is the immobilization of small peptides RGD found in extracellular matrix proteins to promote cell adhesion. Previous studies have revealed that small peptides are relatively stable and can be synthesized with high levels of purity and controlled chemical composition. In this study, we attempted to immobilize the osteopontin-motif peptide (OMP) containing RGD on titanium surface as a means to enhance cell adhesion in bone. The purified OMP peptide was chromatographed on a Ni-NTA resin column, and then immobilized on the titanium surface by chemical treatment. The surface-modified titanium were characterized by FTIR analysis and SEM observation. The MG-63 osteoblast cells was used for the biocompatibility test.The cell morphology and proliferation were measured by SEM and WST-1 assay. FTIR and SEM results showed that the surface of titanium had been grafted the OMP peptide. From the SEM images of cell culture, the cells appeared polygonal,Spindle-shaped,and attached on the surface-modified titanium. The proliferation and activities of MG-63 cells on the OMP-immobilized titanium were better than that on the c.p. Ti. From above results shows that the OMP peptides could enhance cell adhesion ; and could be used in biomaterial eugineering to increase its biocompatibility.