Murata T, Tanioka A
Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152, Japan
J Colloid Interface Sci. 1997 Aug 1;192(1):26-36. doi: 10.1006/jcis.1997.4987.
Lysozyme, albumin, and PAS-H (poly diallyl dimethyl ammonium chloride), which are positively and negatively charged proteins, and cationic polysulfones, respectively, were adsorbed by a cellulose triacetate (CTA) membrane to investigate their effects on ionic transport through the membrane. The interface states between the membrane and the adsorption layer are discussed based on the measurements of contact angle and membrane potential and atomic force microscopy (AFM). The contact angle shows that the membrane changed from hydrophobic to hydrophilic due to adsorption of the above substances. AFM imaged the aggregates on the surface and showed that lysozyme, in particular, penetrates the membrane pores, making them shallower and decreasing their porosity. The results of membrane potential measurements showed that lysozyme and albumin did not change the membrane charge state, but PAS-H changed it from negative to positive. The permeability coefficients of KCl and K2HPO4 varied significantly with the adsorption of each polyelectrolyte. In particular, the permeability coefficient of phosphate through the lysozyme-adsorbed membrane increased to twice that of the nonadsorbed membrane. Such polyelectrolyte adsorption on the membrane surface can be used for the modification of commercial artificial kidney phosphate extraction.
溶菌酶、白蛋白和聚二烯丙基二甲基氯化铵（PAS - H），分别为带正电和负电的蛋白质以及阳离子聚砜，被三醋酸纤维素（CTA）膜吸附，以研究它们对离子通过该膜传输的影响。基于接触角、膜电位测量以及原子力显微镜（AFM）对膜与吸附层之间的界面状态进行了讨论。接触角表明，由于上述物质的吸附，膜从疏水性变为亲水性。AFM对表面聚集体进行了成像，结果显示，特别是溶菌酶会穿透膜孔，使其变浅并降低孔隙率。膜电位测量结果表明，溶菌酶和白蛋白不会改变膜的电荷状态，但PAS - H会使其从负电变为正电。KCl和K2HPO4的渗透系数会随着每种聚电解质的吸附而显著变化。特别是，通过溶菌酶吸附膜的磷酸盐渗透系数增加到未吸附膜的两倍。这种聚电解质在膜表面的吸附可用于商业人工肾磷酸盐提取的改性。
