藍藻蛋白(Cyanophycin granule polypeptide)是一種非核醣體合成蛋白質，其結構是由天門冬氨酸(aspartic acid)為主鏈，精氨酸(arginine)與離氨酸(lysine)為側鏈所組成的聚合物；而明膠是由部分水解性的天然膠原蛋白所組成，主要為一重複連續的甘氨酸(glycine)-脯氨酸(proline)-基脯氨酸(hydroxiproline)序列及其他胺基酸所構成的分子。
　　明膠與藍藻蛋白具有良好的生物相容性，但由於藍藻蛋白其彎曲強度和韌性較差，限制了藍藻蛋白的應用範圍，而明膠具有親水性(Hydrophilic)良好、成膜性佳與顯著的機械性能(mechanical)等優點，故本研究目的是以戊二醛(glutaraldehyde)進行交聯反應製備不同比例的明膠/藍藻蛋白複合膜，期望能增強其材料的機械性質及提高皮膚纖維母細胞的生長。
　　本實驗將明膠與藍藻蛋白共混成溶液後進行交聯反應，以製備成不同比例之複合膜，隨後以掃描式電子顯微鏡(scanning electron microscope, SEM)觀察複合膜其表面和切面結構，並使用材料試驗機進行機械性質的量測，與熱重差分析法(thermogravimetric analysis, TGA)對複合膜的裂解點進行測試，且包含了含水率(swelling)及接觸角的測量；並使用皮膚纖維母細胞在不同比例複合膜上進行培養，以MTT法測試其相對存活率。
　　實驗結果顯示，在SEM的材料表面觀察與接觸角測量中，觀察到複合膜隨著藍藻蛋白的所占含量的提高，孔洞與層狀結構更臻明顯；而在機械性質的測試中看出，適量的材料共混有助於提升其抗拉強度；從TGA量測結果發現，使用水溶性藍藻蛋白成膜的組別，會有兩段的裂解溫度表現，推測是水溶性藍藻蛋白成膜的組別交聯反應較佳，升溫過程中交叉鏈接的部分會被先行裂解，而產生此現象。在吸水率方面，看出複合膜會隨明膠所占比例越少，吸水率隨之減少。在明膠/藍藻蛋白複合膜經72小時的皮膚纖維母細胞培養後，可得知其材料有助於細胞的生長。
　　從上述結果可歸納出，適量的藍藻蛋白與明膠共混有助於提升其抗拉強度，可擴大藍藻蛋白的應用範圍，並提高纖維母細胞的生長。

　　Cyanophycin granule polypeptide (CGP) is a non-ribosomal synthesis protein. The polymer consists of an aspartic acid backbone with arginine and lysine as side chains. Gelatin is composed of partial hydrolysis of collagen, and is the product of almost continuous repeats of the glycine- proline -hydroxyproline sequence.
　　Gelatin and CGP have good biocompatibility. However, the strength and toughness of CGP is poor, which limits its applications. The gelatin has good hydrophilicity, film forming and mechanical properties. In this study, we prepared different ratios of gelatin/CGP composite scaffolds by cross-linking reaction with glutaraldehyde in an effort to improve the mechanical properties of the composite material and the growth of skin fibroblast.
　　We mixed different ratios of gelatin and CGP in solution and the mixture was cross-linked with glutaraldehyde. We used scanning electron microscopy (SEM) to observe the surface, cross-section and cell attachment morphology of the composite scaffolds. A universal test machine was used to detect the tensile strength and elongation of the material. The decomposition temperatures were measured by thermogravimetric analysis(TGA), and the hydrophilicity was examined by a contact angle meter. The growth of skin fibroblast was monitored by MTT assay.
　　The results showed that the pore and layer structures became more evident with an increasing percentage of CGP. The mechanical test showed that the mixture of CGP and gelatin can improve the tensile strength at an optimal ratio of gelatin and CGP . The composite of soluble CGP cross-linked with gelatin showed two decomposition temperatures by TGA analysis. The composites also provided a better cell growth environment for skin fibroblast on the gelatin/CGP composite scaffolds.
　　In conclusion, the composite of CGP cross-linked gelatin can improve the tensile strength and the growth of fibroblasts which extend the applications of CGP.

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