以醣類分子修飾幾丁聚醣生醫材料對其細胞相容性之影響

Cytocompatibility of sugar-modified chitosan biomaterials

蔡睿逸(Rui-Yi Tsai)

指導教授 ： 謝學真

國立臺灣大學/工學院/化學工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.01043

摘要

幾丁聚醣具有良好的生物相容性、生物可分解性、無毒性以及抗菌能力等優點，使幾丁聚醣成為近年來頗受重視的天然高分子生醫材料。由於幾丁聚醣本身的親水能力較差，為增進其在生醫材料應用上的廣度，可採用較具親水性的材料對幾丁聚醣進行改質。本研究分別以加熱法及添加交聯劑方式將單醣（葡萄糖酸、葡萄糖、半乳糖）及雙醣（乳糖）等親水性分子接枝於幾丁聚醣基材表面，隨後測量基材表面的親水性，另以FTIR測定其官能基變化，再於其表面進行細胞培養，以觀察細胞在修飾過後的幾丁聚醣基材上之貼附及生長狀況，藉此探討醣類分子修飾對幾丁聚醣基材細胞相容性之影響。
在醣類分子修飾程度（取代度）方面，加熱（60℃）對醣類與幾丁聚醣間的接枝反應效率有顯著的提升，添加交聯劑EDC與NHS可進一步增進葡萄糖酸與幾丁聚醣的接枝反應而提高醣類取代度，至於單純添加還原劑NaBH4對促進醣類與幾丁聚醣之間的作用則不是很明顯。在親水性測試方面，經過醣類修飾的幾丁聚醣其親水性有明顯上升，尤其接上葡萄糖對於幾丁聚醣的親水性助益最大。在細胞測試方面，大白鼠骨瘤（rat osteosarcoma, ROS）細胞在加熱法做醣分子修飾之幾丁聚醣基材上貼附及生長狀況較好，短時間（24小時）內細胞數量幾近於在細胞培養專用的TCPS基材上的細胞數， ROS細胞在添加交聯劑做醣分子修飾之幾丁聚醣基材上貼附效率略差，其原因可能是交聯劑的存在對於細胞生長會有不良的影響。而改以牙齦纖維母細胞（gingival fibroblast, GF）培養在各種幾丁聚醣基材上，發現GF細胞的生長狀況均不佳，原因可能是醣類取代度不夠高，使得修飾後的基材與GF細胞之間的相容性仍不佳，有待進一步改善。

關鍵字

幾丁聚醣 ； 醣類 ； 細胞相容性

並列摘要

Chitosan is a natural polycationic biomaterial which possesses biocompatibility, biodegradability, nontoxicity and anti-microbial capability. People use hydrophilic materials to modify chitosan in order to enhance its hydrophilicity and thus broaden its application in biomaterial-related fields.
This study focused on the cytocompatibility of sugar-modified chitosan biomaterials. Monosaccharides (gluconic acid sodium salt, glucose, galactose) and disaccharide (lactose) were conjugated on the chitosan film surface by heating or cross-linking reagent. The hydrophilicity of chitosan film was indicated by the contact angle on the surface. The change in functional groups on the film surface was investigated by FTIR. The cytocompatibility of sugar-modified chitosan was determined by the attachment and spreading of rat osteosarcoma (ROS) cells on the chitosan film.
The results of the degree of modification (substitution of sugars) of chitosan film indicated that heating accelerated the reaction between sugar and chitosan. Besides, addition of cross-linking reagents EDC and NHS also promoted the reaction between gluconic acid and chitosan. However, the addition of sodium borohydrate (NaBH4) did not have significant effect. The attachment and spreading of ROS cells was good on a sugar-modified chitosan film that was heat-treated at 60℃ and the amount of cell number was near that on TCPS within the initial 24 hours. However, the attachment and spreading of ROS cells on a sugar-modified chitosan films that was treated by cross-linking reagents was not as good as that on a heat-treated chitosan film. A possible reason was that the residual cross-linking reagents might influence the attachment and proliferation of ROS cells. Our results also indicated that the attachment and proliferation of gingival fibroblasts on sugar-modified chitosan films was poor. One of possible reasons was that the degree of modification (substitution of sugars) was not high enough to get satisfactoty interaction between gingival fibroblasts and chitosan.

並列關鍵字

chitosan ； saccharide ； cytocompatibility

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