Reuben B G, Perl O, Morgan N L, Stratford P, Dudley L Y, Hawes C
South Bank University, London, UK.
J Chem Technol Biotechnol. 1995 May;63(1):85-91. doi: 10.1002/jctb.280630112.
The aim of the present work was the development of phosphorylcholine-based treatments for biofiltration membranes and the demonstration that such treatments prevent or inhibit protein fouling. Microfiltration membranes of cellulose triacetate, polyether sulphone and polyvinylidene fluoride were etched with oxygen in a plasma chamber to generate surface hydroxyl groups and were then treated with the monomer 2-methacryloyloxyethyl phosphorylcholine. These membranes were evaluated with water, buffer, bovine serum albumin (BSA), yeast fermentation broth, beer and orange juice. The treatment of cellulose triacetate membranes reduced both the initial flux and the extent of water fouling. In terms of the integrated flux, these factors tended to cancel each other out. For protein, the membranes gave similar or higher fluxes but worse fouling. The cellular feed (yeast) reacted more favourably to the coating than the BSA. The polyether sulphone was scarcely affected by the coating; fouling remaining high with most 'real' feeds. There was lower initial flux but less flux decline with water and beer. Washing with water and cleaning with Tergazyme did not restore the initial flux. Polyvinylidene fluoride membranes gave the most positive results. In most cases, the coating both increased initial flux and decreased the rate of fouling. The coating was particularly effective for BSA and for beer and orange juice, where fouling is probably caused by a polysaccharide rather than by a protein. Electron microscopy showed, nonetheless, that fouling by proteins was accompanied by protein adsorption primarily on the upper surface of the membrane and that coated membranes showed less deposition and in different places than did untreated membranes.
本研究的目的是开发用于生物过滤膜的基于磷酸胆碱的处理方法，并证明这种处理可预防或抑制蛋白质污染。将三醋酸纤维素、聚醚砜和聚偏二氟乙烯的微滤膜在等离子体室中用氧气蚀刻以产生表面羟基，然后用单体2-甲基丙烯酰氧基乙基磷酸胆碱进行处理。这些膜分别用水、缓冲液、牛血清白蛋白（BSA）、酵母发酵液、啤酒和橙汁进行评估。三醋酸纤维素膜的处理降低了初始通量和水的污染程度。就积分通量而言，这些因素往往相互抵消。对于蛋白质，这些膜的通量相似或更高，但污染更严重。细胞进料（酵母）对涂层的反应比BSA更有利。聚醚砜几乎不受涂层影响；在大多数“实际”进料下污染仍然很高。用水洗涤和用特洁尔酶清洗不能恢复初始通量。聚偏二氟乙烯膜的效果最为理想。在大多数情况下，涂层既增加了初始通量又降低了污染速率。该涂层对BSA、啤酒和橙汁特别有效，在这些情况下，污染可能是由多糖而非蛋白质引起的。尽管如此，电子显微镜显示，蛋白质污染伴随着蛋白质主要吸附在膜的上表面，并且与未处理的膜相比，涂覆的膜在不同位置的沉积更少。
