現有應用在修飾醫療器材表面的方法，往往受限於器材大小與修飾材料的化學組成。在此限制下，發展能修飾在多種表面上，且又能進一步做功能化修飾的方法，是目前發展表面修飾的重大課題。在本篇研究，我們利用多酚(polyphenol)與鐵離子，在水溶液中能形成複合物(complex)的現象，發展出具備一步驟簡單，且不受限基板大小及化學組成的修飾方法。後續並加入兩性雙離子材料，於各種基材表面進行改質而達到抗生物汙染的功能。此篇利用兩性離子多巴胺磺基甜菜鹼（sulfobetaine-dopamine, SB-DA）以達抗生物汙染之特性；單寧酸(Tannic acid, TA)與二價或三價鐵離子形成複合物(metal–phenolic complex network, MPN)，以達適用於多樣基材表面修飾的目的。因多酚(polyphenol)與二價或三價鐵離子皆能形成複合物，首先用UV-VIS計算單寧酸及多巴胺磺基甜菜鹼，與二價或三價鐵離子間的平衡常數。再利用水接觸角和X射線光電子能譜，了解結合MPN與SB-DA修飾後的親水性質、表面元素組態。並藉由綠膿桿菌和表皮葡萄球菌細菌貼附，纖維母細胞貼附，比較利用不同價數的鐵離子與單寧酸、多巴胺磺基甜菜鹼修飾的薄膜，是否有不同抗生物汙染程度。其中，在XPS結果，於Fe2+MPN/Fe2+的薄膜上修飾多巴胺磺基甜菜鹼，其效果比於Fe3+MPN/Fe3+的薄膜上有更高的密度。在Fe2+MPN/Fe2+/SB-DA修飾條件下，表面水接觸角約為5度；細菌貼附實驗結果，可抵抗約85%的綠膿桿菌和表皮葡萄球菌的貼附；細胞貼附實驗結果，則可抵抗約80%的纖維母細胞貼附。本研究發展了一種新的修飾方法，可於各種基材表面進行改質而達到抗生物汙染的功能，並期待開發多功能生物界面且應用於醫療器材表面塗層，以提升其生物相容性與使用安全性。;The development of facile and versatile strategies for surface engineering has attracted considerable attentions in various aspects of applications. However, only few methods can be applied to substrates with different compositions, sizes, and shapes. In this study, we report a newly developed approach to fabricating an antifouling coating via coordination of polyphenols and metal ions in an aqueous solution. This approach incorporates bioinspired zwitterionic sulfobetaine dopamine (SB-DA) for fouling resistance in which tannic acid (TA) and metal ions serve as crosslinking agents. Film formation was accomplished with the adsorption of the metal–phenolic complex network (MPN) on various planar organic and inorganic substrates. Because of super hydrophilic and charge-balanced properties, SB-DA enables forming a tightly bound water layer on the top of the complex network to repel nonspecific adsorption. Here we compared two metal ions: ferrous ion (Fe2+) and ferric ion (Fe3+). Their stabilities with phenol groups were estimated by measuring the binding constant and being determined spectrophotometrically. The surface hydration of the modified substrates was tested by contact angle goniometer; the surface elemental composition and the chemical states of the modified substrates were confirmed by and X-ray photoelectron spectroscopy (XPS). For examining the antifouling properties, we immersed the modified substrates into the solutions containing bacteria or cell. Thus, the adsorbed bacteria and cell were quantified using fluorescence microscopy and cell imaging analysis. We applied the coating strategy onto various substrates, including silica, noble metals, metal oxides, and polymers. The results show that zwitterionic SB-DA can be coated on the different surfaces via assembly of MPN and also provide an antifouling property. Consequently, this approach for substrate modification offers an easy, fast and environment friendly way to realize biocompatible coatings for all types of substrates. The work also provides insight into the construction of hierarchical structures by molecular assembly for functional biointerfaces.
