膜上荷电量对超滤膜的渗透性和牛血清蛋白透过率影响的研究

Effects of charge on ultrafiltration membrane permeability and bovine serum albumin sieving

改变化学反应时间获取一系列荷电量不同的改性再生纤维素(RC)超滤膜,定量地考察了超滤膜上荷电量对膜的渗透性和牛血清蛋白(BSA)透过率的影响.研究结果表明:反电渗透现象造成荷电量不同的超滤膜上的水透过系数均减小,减小的程度与膜的荷电量和溶液离子强度有关;溶液pH值为7.0的条件下,荷负电的BSA与荷负电改性RC膜之间的静电相互作用,使BSA的透过率减小,减小的程度同样与膜的荷电量和溶液离子强度有关.研究结果提供了荷电量对超滤膜渗透性和BSA透过率影响的定量数据;揭示了相对于传统超滤膜而言,荷电超滤膜具有更好的渗透性和分离选择性相结合的优势.

A series of charge-modified regenerated cellulose membranes with the surface charge density were obtained by varying the time of chemical reaction.Effects of the membrane surface charge on permeability and sieving coefficient of bovine serum albumin（BSA） were investigated quantitatively.Results showed that the effect of counter-electroosmosis caused the permeability decrease and the decreasing degree is related to the solution ionic strength and membrane charge.At pH=7.0,due to the electrostatic repulsion between negatively-charged BSA and negatively-charged RC membrane,the sieving coefficient of BSA decreased and the decreasing degree is also related to the solution ionic strength and membrane charge.Results provided the quantitative data on the effect of membrane charge on permeability and BSA sieving,and also indicated that the charged ultrafiltration membrane would provide a better combination of permeability and selectivity compared to the traditional ultrafiltration membrane.