生物汙染是蛋白質、細胞或細菌等非特異性吸附於表面上，進而而形成血栓和生物膜。本研究提出一種通用基材表面修飾方式，使表面同時具有抵抗非特異性吸附，及抗菌的功能。本研究利用CuSO4及H2O2加速多巴胺的聚合與沉積速率，使表面於短時間內形成聚多巴胺層，且可同時螯合溶液中的銅離子(Cu2+)於表面上，並藉由銅離子釋放達到殺菌效果。形成的pDA功能薄膜後，再藉由aza-Michael addition反應方式接枝雙離子材料丙烯醯胺磺基甜菜鹼 (sulfobetaine acrylamide，SBAA)，形成具有超親水之抗非特異性貼附之生物界面。利用接觸角測角儀 (contact angle) 進行表面鑑定，在接枝SBAA後的條件下，表面水接觸角約為5度，具有良好的親水性質。在X射線光電子能譜儀 (x-ray photoelectron spectroscopy)顯示，修飾後的表面上，具有銅離子及SBAA的元素組態。而於細菌貼附實驗測試，經SBAA修飾後，可抵抗約90%、95%的大腸桿菌(E-coli)及表皮葡萄球菌(S.epidermidis)之貼附，且其中80%為死菌。最後將材料修飾於尿導管表面上，並由此證明，藉由銅離子的釋放達到抗菌的效果，且修飾後的表面具有良好抗細菌貼附特性。本研究開發無表面選擇之生物啟發抗菌塗層，不但可抵抗細菌的非特異性貼附(antifouling)，更利用銅離子作為殺菌劑，成為雙重功能(antifouling與antimicrobial)之萬用生物界面塗層，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 formation of bacterial biofilms on indwelling medical devices generally causes high risks for adverse complications such as catheter-associated urinary tract infections. In this study, we report a simple, rapid approach to imparting durable antibacterial properties to various surfaces. Initially, we use CuSO4/H2O2 to accelerate the polymerization of dopamine and the deposition rate of polydopamine. The pDA-assisted immobilization of copper ions enables the surfaces to incorporate antimicrobial agents for adsorbed and planktonic bacteria. Then, the fouling properties were achieved by grafting zwitterionic sulfobetaine acrylamide (SBAA) onto the pDA films via the aza-Michael addition. The surface chemical compositions upon pDA modification and subsequent conjugation were monitored with X-ray photoelectron spectroscopy (XPS) and water contact angle measurements. Antifouling properties of coatings were challenged by Escherichia coli and Staphylococcus epidermidis. The results show that pDA coatings grafted with SBAA exhibited superhydrophilicity and excellent fouling resistance. In addition, copper ions exhibit excellent antibacterial activity. The composite coatings allowed reduction of adsorption of Escherichia coli and S.epidermidis by 90% and 95%, respectively, while appearing up to 80% of dead bacteria upon the release of copper ions as measured by inductively coupled plasma mass spectrometry. Moreover, the composite coatings have been applied on the silicone-based urinary catheters to avoid the growth of bacteria and infection. Consequently, we have presented a facile and universal approach to modify surfaces and accordingly providing antibacterial properties. This strategy provides a useful route to mitigating the long-term biofouling of various surfaces.
