藍藻蛋白為生物可降解的高分子，經由基因重組生產藍藻蛋白，其成分由aspartic acid、arginine以及lysine所構成，而lysine上的一級胺比arginine更容易進行化學修飾。本研究是利用不同的交聯劑將lysine上的一級胺與低分子量的聚乙烯亞胺(Polyethylenimine，PEI，2 kDa)接合起來，所使用的交聯劑為glutaraldehyde、glucose、genipin，都能與一級胺反應，目的是希望可以利用此高分子有效地轉染細胞。
藉由DNA電泳可以判斷接合物對DNA的包覆能力，以glucose、glutaraldehyde、genipin交聯藍藻蛋白與PEI(2 kDa)的接合物都能有效的包覆DNA，因此可以再近一步對動物進行細胞轉染實驗。
對CHO cell轉染結果，從螢光顯微鏡下的綠色螢光蛋白的表現中，發現以glucose交聯藍藻蛋白與PEI(2 kDa)的接合物相較於以glutaraldehyde與genipin交聯的接合物，綠色螢光蛋白的表現相對較多。但是對於高分子量的聚乙烯亞胺(25 kDa)，綠色螢光蛋白的表現是相對的少許多。轉染後接著進行毒性測試，由存活率可看出glucose交聯的接合物對細胞不具毒性。
藍藻蛋白與PEI(2 kDa)以glucose交聯能有效地包覆DNA以及送入細胞中，但未來可改變PEI(2 kDa)的 比例來評估能否提升轉染效率，有機會當作良好的基因傳遞載體。

Cyanopycin can be produced by recombinant Escherichia coli. It is a biodegradable polymer that consists of aspartic acid, arginine and lysine. The primary amine of lysine is easier to be chemically modified than the functional groups of arginine. In this study, we utilized the primary amine of lysine and low molecular weight polyethylenimine (PEI) to be cross-linked by different cross-linking reagents (glutaraldehyde, glucose, and genipin). The cross-linking reagents can react with primary amines. We expect that the cross-linked products can be used to transfect cells effectively.
By DNA electrophoresis, we found that the cross-linked products by glutaraldehyde, glucose, and genipin have the ability to encapsulate DNA. We further transfected mammalian cell to examine the expression of green fluorescent protein.
The results of transfection of Chinese Hamster Ovary (CHO) cells were observed under a fluorescent microscope. The cross-linked products by glucose resulted in a higher expression level of green fluorescent protein in comparisons with the other products by glutaraldehyde and genipin. However, the transfection efficiencies of those cross-linked products are not as good as that of high molecular weight PEI. The MTT assay was used to investigate the cellular viability after transfection. The results also showed that the cross-linked products by glucose are nontoxic.

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