摘要:
A two-step surface modification method was employed to mitigate the interaction between proteins and membrane surface.Firstly,the tertiary amine hydrogen donor (N,N-dimethyl-3-aminopropyl) trimethoxysilane (DMAPS) was coupled to the surface of the ceramic membrane by silylation reaction,and then the sodium 2-bromoethyl sulfonate (SBTS) generate quaternization reaction with DMAPS that finally fabricating zwitterion ceramic composite membrane (SBTS-c-DMAPS-g-Al2O3).Contact angle(CA) measurements demonstrated that the contact angle reduced from 36° to 21° comparing unmodified membrane and modified membrane,which indicating zwitterion modification effectively increased the membrane hydrophilicity,and arousing the pure water permeability improved by 20%;The zwitterions modified ceramic composite membranes were applied in the filtration of bovine serum albumin (BSA) solution.Compared with the BSA permeability of unmodified membrane,the BSA permeability of modified membrane heighten by 30%,.In addition,the results showed that BSA could be easily eluted from the fouled surface of the modified membranes after cleaning,and the flux recovery was above 90%(the flux recovery of the unmodified membrane was only 20% or so).The zwitterions were considered to be responsible for reducing the protein adsorption on the membrane surface and pore walls because of the hydration layer formation of zwitterionic membrane surface during filtration,which contributed to the easy-cleaning properties of zwitterions modified ceramic composite membranes.%为了减弱蛋白与陶瓷膜表面的作用力,采用两步表面接枝法,首先采用硅烷化反应将叔胺氢给体(N,N-二甲基-3-氨丙基)三甲氧基硅烷(DMAPS)偶联到含有羟基的陶瓷膜表面,再引发2-溴乙基磺酸钠(SBTS)在膜表面发生季铵化反应,制备磺酸型两性离子陶瓷复合膜(SBTS-c-DMAPS-g-Al2O3).结果表明:红外光谱测试显示,与未改性膜表面相比,改性膜表面于1 065 cm-1和1 200 cm-1处分别出现C-N峰与SO3-峰.接触角测试结果表明,膜的亲水性得到改善,膜表面水滴接触角由36°减小到21°,纯水通量增大20%,可间接表明材料表面成功接枝上两性离子.牛血清白蛋白(BSA)的动态过滤实验表明,改性膜对BSA溶液渗透率比未改性膜的BSA溶液渗透率高30%,改性膜被污染后,再用纯水清洗后的纯水通量恢复率达到90%,而未改性膜被污染后,再用纯水清洗后的纯水通量恢复率只有26%.这是因为两性离子陶瓷复合膜具有易清洗性能.