醫療器材表面的蛋白質及微生物的非特異性吸附容易引發諸如凝血反應、微生物感染以及組織鈣化等生物自發性的各項負面效應。過去研究證明表面電中性的親水性修飾能有效降低非特異性吸附。然而在矽利康（silicone）材料方面，由於其本身的高度疏水再生性質（hydrophobic regeneration），造成難以在材料表面上進行穩定的親水性修飾。本研究以帶有矽烷官能基的磺甜菜鹼兩性離子分子（sulfobetainesilane, SBSi）在聚二甲基矽烷（polydimethylsiloxane, PDMS）矽利康材料進行自組裝單層膜（self-assembled monolayers, SAMs）修飾，已獲得親水性表面修飾的矽利康基材並進一步證明能抵抗非特異性吸附。以X光光電子能譜儀（X-ray photoelectron spectroscopy, XPS）分析表面原素成分。以接觸角側角儀（contact angle goniometer）判斷親水材料修飾的效果以及隨著時間在空氣中保存的材料表面親水修飾之穩定性。修飾後的矽利康基材對於表皮葡萄球菌（Staphylococcus epidermidis）和綠膿桿菌（Pseudomonas aeruginosa）有顯著的抗細菌吸附效果。抵抗蛋白質貼附的方面本研究也成功測試了修飾後的矽利康基材對於牛血清白蛋白（bovine-serum-albumin, BSA），黏蛋白（mucin）以及溶菌.（lysozyme）有良好的抵抗效果。以包覆磺酸羅丹明B （Sulforhodamine B，SRB）的微酯體證明抵抗酯質貼附能力。並成功使磺甜菜鹼兩性離子分子修飾後的矽利康水膠軟式隱形眼鏡（silicone hydrogel soft contact lens）抵抗綠膿桿菌之黏附。利用本研究的成果，可以將矽利康在醫療照護上更安全且更有效發揮其功能。最後，我們利用SBSi超親水的特性，使表面具有抗霧、自潔的功能，並成功製備油水分離系統，以快速回收純水。

Biofouling on biomaterials causes adverse consequences to health, such as thrombosis, infection, and pathogenic calcification. Hydrophilic and charge-balanced surface is proved to resist the nonspecific absorption. Unfortunately, the state-of-art technology for silicone modification cannot provide a stable and effective coating for the long-term applications under complex conditions. In this study, we aim to modify the silicone surfaces with a zwitterionic surface ligand to resist nonspecific adsorption of protein and bacteria. We synthesized a silanized surface ligand conjugated with a head residue of zwitterionic sulfobetaine (SBSi) that bears positively charged quaternary amine and negatively charged sulfonate. Surface elemental composition was confirmed by X-ray photoelectron spectroscopy (XPS) and the stability of hydrophilicity modification was tested by contact angle goniometer. The tests for adsorption of bacteria, protein, and liposome revealed the excellent antifouling properties of modified silicones. For the real-world application, we modified commercially available silicone hydrogel contact lenses with developed zwitterionic ligands and showed their capability of anti-bacterial adhesion. The strategy of surface engineering in this work can be applied to other silicone-based medical devices in facile and effective fashion. Moreover, we employed the super hydrophilicity of SBSi for preparing anti-fogging, self-cleaning surfaces. We accomplished a water-oil separation system for effective recovery of fresh water.

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