膠原蛋白是哺乳動物中含量最豐富的蛋白質，現今已廣泛應用於生醫材料上，為了增加其應用性，需要尋找更有效的製備方法使短的模擬膠原蛋白胜肽能夠進行自組裝以形成高階結構，本實驗中我們利用兩種策略誘發膠原蛋白自組裝。首先，我們將組胺酸引入模擬膠原蛋白胜肽，在含有金屬離子的溶液中，藉由組胺酸與金屬離子的配位關係誘發膠原蛋白胜肽自組裝形成高階超分子結構，而此自組裝過程在加入金屬離子螯合劑 EDTA 後即進行逆反應使高階結構瓦解。實驗結果顯示組胺酸與金屬離子的配位鍵能提供有效的作用力誘發模擬膠原蛋白胜肽自組裝成高階大尺度結構，而且藉由調整配位條件可以改變此高階結構的形貌。
另外，我們引入cation-π 作用力，在模擬膠原蛋白胜肽氮端和碳端分別加入精胺酸和苯丙胺酸，期望這兩種胺基酸間能在模擬胜肽分子間形成 cation-π 作用力，而促進膠原蛋白胜肽進行自組裝。實驗結果顯示模擬膠原蛋白胜肽能快速地以頭接尾方式自組裝形成高階纖維狀結構，說明藉由 cation-π 作用力能成功誘發膠原蛋白胜肽自組裝，而此結果提供了另一個簡單且有效率的方法來製備膠原蛋白相關的生醫材料。

Collagen, the most abundant protein in mammals, has been widely used in biomedical materials. Searching for an effective way to assemble short mimetic collagen peptides into a higher order structure has been an emerging topic for the preparation of collagen-related biomaterials. In this work, we have incorporated histidine residue into two mimetic collagen peptides to promote the self-assembly of short collagen triple helices into supermolecular structure via His-metal coordination. Our results indicate that His-metal coordination can serve as an effective force to assemble mimetic collagen peptides into large scale structures and their topology depends on metal ions and His-metal coordination sites. Furthermore, the process of self-assembly can be reversed upon adding the cation chelator, EDTA, in solution.
In addition, we have introduced a cationic residue into the N-terminus and an aromatic residue into the C-terminus of a collagen-related peptide which can generate favorable cation-π interactions between the termini of collagen triple helices. The experimental results demonstrate that cation-π interactions can promote the self-assembly of collagen triple helices into higher-order fibril structures in a head-to-tail manner. The work shows that cation-π interactions can serve as an effective force in preparing collagen-related biomaterials.

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