摘要: | 雙離子性(zwiiterionic)材料為依同時具有正電荷及負雙離子性(zwiiterionic)材料為依同時具有正電荷及負電荷官能基於同一單體而成一電中性之結構,其已被證實具有良好的抗生物積垢能力,但由於其具極佳之親水性,因此不易改質製疏水性材料表面。因此本篇研究擬合成一同時具有疏水性長鏈與雙離子性結構片段的共聚物,使其疏水性長鏈可以利用疏水性作用力附著於疏水性聚碸(Polysulfone, PSf)濾膜上,而暴露在外的雙離子性結構可用以對抗生物分子之沾黏。在本研究中選用2,5呋喃二酮與1-十八烯的共聚物(poly(maleic anhydride-alt-1-octadecene), MAO)與N,N-二甲基-1,3-二氨基丙烷(3-(dimethylamino)-1-propylamine, DMAPA)進行開環反應得到一同時具有疏水性長鏈與雙離子性結構片段的兩性共聚物MAO-DMAPA,並藉由核磁共振光譜儀(1H-NMR)分析其化學結構。
接著將MAO-DMAPA與PSf進行摻合(Blending),再利用濕式相轉換法(Non-solvent induced phase separation, NIPS)製備出不同環境成膜之改質過後的薄膜,並且量測在不同pH值環境下,不同摻合量的PSf膜對於牛血清蛋白(Bovine serum albumin, BSA)與溶解酶(Lysozyme)的吸附量變化,同時由蛋白質靜態吸附實驗結果中挑選具有較佳抗蛋白質吸附能力的薄膜進行蛋白質過濾實驗與大腸桿菌E.coli.的貼附實驗。由各項測試的結果可得知,在70% EtOH環境下成膜,3.6wt%MAO-DMAPA摻合量的PSf膜具有良好的抗蛋白質吸附能力。
In recent years, the zwitterionic copolymers were paid much attention to use for modifying the membranes for the purpose of antifouling. In our study, we have designed an amphiphilic and zwitterionic copolymer MAO-DMAPA synthesized from poly(maleic anhydride-alt-1-octadecene) (MAO) and 3-(dimethylamino)-1-propylamine (DMAPA), then we used different MAO-DMAPA content to blend with polysulfone (PSf) and fabricate the ultrafiltration (UF) membrane by the non-solvent induced phase separation (NIPS) method under 0% and 70% EtOH/H2O mixture surrounding. After membrane preparation, we use the bovine serum albumin(BSA) and lysozyme to measure the protein adsorption resistance of membranes. For these two proteins, we found that the maximum of protein binding capacity and dissociation constant were decreased with elevating the blended MAO-DMAPA content. Finally, we found that the membrane formed under 70% EtOH has superior protein resistance. Then we did the MAO-DMPA titration curve to distinguish the pKa value of the tertiary amine and carboxyl group on MAO-DMAPA. According to the titration curve, we conducted the protein resistance of blended MAO-DMAPA membranes at different pH value surroundings by protein filtration. We got that 70% M-3.6 has higher flux and the best low-protein adsorption ability of those membranes. After protein adsorption experiment, we choose the 70% M-3.6 to carry out E.coli. adhesion. From the result, we can find that 70% M-3.6 has lower amount of E.coli. colonies than M-0. Therefore, we verify blending MAO-DMAPA contributed to improve the low-biofouling ability. |