自組裝單分子膜為有機分子吸附於底材表面所構成，因此藉
由改變有機分子成分，便可輕易地控制表面特性。所以在微機電
技術上，自組裝單分子膜的應用相當廣泛，如微流體的輸送與增
加蛋白質檢測效率等。進一步了解自組裝單分子膜的物理機制，
將有助於應用上的設計。表面特性是因物體與表面間分子作用所
造成的，而分子動力學主要所探討的便是分子間的作用。所以在
表面特性的研究上，分子動力學模擬便成了極為有力的工具。
此研究使用了分子動力學模擬，探討了在混合不同種類有機
分子之自組裝單分子膜的表面現象。主要可分為兩部分：第一部
分探討混合自組裝單分子膜表面的濕潤現象，以助於微流體輸送
上的應用；第二部分則探討蛋白質與混合自組裝單分子膜間的吸
附現象，以作為生物晶片設計上的參考。第一部分以接觸角來決
定表面濕潤程度。目前初步發現，接觸角皆會因混合比例不同而
造成差異，但在混合不同鏈長的表面，其差異並不明顯；而在混
合不同官能基的表面，則有著顯著的差異，其原因應為OH基與水
分子間產生氫鍵所造成。未來希望能藉由計算表面張力，進一步
對表面的濕潤現象作量化分析。第二部分利用計算蛋白質與表面
分子間的束縛能，作為決定其吸附程度的依據。初步發現其之間
束縛能會因混合比例產生變化，至於更詳細的探討，仍待未來建
立更詳細的系統（考慮水分子的效應）才能確定。

The self-assembled monolayers (SAMs) provide viable means of controlling both physical and chemical properties of a solid surface. This work intends to extend the applicaiton to microfluidic system and protein sensing by molecular dynamics. Molecular dynamics (MD) simulations is a well established tool to understand the properties of complex molecular system, which is a very fundamental method to describe physics in molecular size, especially for the intermolecular interactions.
Two model systems are studied: (1)Wetting phenomena of alkanethiol SAMs and their mixture on Au(111) surface; (2)Binding strength and orientations of protein (e.g., E6) on SAMs with different chain length. The simulations of the first system show that the modification of terminal group to OH is very effective for the increase of hydrophilic degree. The simulations of the second system show that
the binding energy between protein and SAMs are varied with the mixed ratio of SAMs and orientations. Further studies on the full system (including water molecules) will be performed to confirm the observations.

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