Layer-by-layer Assembled Membranes with Immobilized Porins.
Layer-by-layer Assembled Membranes with Immobilized Porins.
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逐层组装的膜，带有固定的孔蛋白。
DOI：
10.1039/c7ra08737c
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发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
Bhattacharyya D
中科院分区：
文献类型：
--
作者：
Hernández S;Porter C;Zhang X;Wei Y;Bhattacharyya D
随着用于选择性分离的膜的合成和功能化，反应性和刺激响应行为出现了新的和先进的机会。生物通道的集成是膜技术的进步之一。通过聚电解质的逐层组装，将来自大肠杆菌的外膜蛋白F三聚体(OmpF)或“孔蛋白”固定在聚偏氟乙烯微滤膜的孔内，而不是传统的脂双层或囊泡破裂过程，其中心孔径约为2 nm，收缩区域约为0.7×1.1 nm。这些OmpF-膜表现出对非带电有机物的选择性截留而不是离子溶质，允许通过的盐分比传统纳滤膜高2倍，对0.4-1.0 kDa有机物的截留率为84%。OmpF膜中带电基团的存在也通过Donnan排斥导致pH依赖的盐排斥。这些OmpF-膜还表现出卓越的耐用性和稳定性，在超过160小时的操作中提供一致和恒定的渗透性和恢复率。在过程的每个阶段都对含有OmpF的溶液和膜进行了表征，包括荧光标记(FITC)检测、Zeta电位、pH响应性、通量变化和有机-无机溶液的截留率。
With the synthesis and functionalization of membranes for selective separations, reactivity, and stimuli responsive behavior arises new and advanced opportunities. The integration of bio-based channels is one of these advancements in membrane technologies. By a layer-by-layer (LbL) assembly of polyelectrolytes, outer membrane protein F trimers (OmpF) or “porins” from Escherichia coli with a central pore of ~2 nm diameter at its opening and ~0.7 × 1.1 nm at its constricted region are immobilized within the pores of poly(vinylidene fluoride) microfiltration membranes, as opposed to traditional ruptured lipid bilayer or vesicles processes. These OmpF-membranes demonstrate selective rejections of non-charged organics over ionic solutes, allowing the passage of salts up to 2 times higher than traditional nanofiltration membranes starting with rejections of 84% for 0.4–1.0 kDa organics. The presence of charged groups in OmpF membranes also leads to pH-dependent salt rejection through Donnan exclusion. These OmpF-membranes also show exceptional durability and stability, delivering consistent and constant permeability and recovery for over 160 h of operation. Characterization of solutions containing OmpF, and membranes were conducted during each stage of the process, including detection by fluorescence labelling (FITC), zeta potential, pH responsiveness, flux changes, and rejections of organic-inorganic solutions.