Miyauchi E, Togawa Y, Makino K, Ohshima H, Kondo T
Faculty of Pharmaceutical Sciences, Tokyo, Japan.
J Microencapsul. 1992 Jul-Sep;9(3):329-33. doi: 10.3109/02652049209021247.
Permeation of electrolyte ions through poly(L-lysine-alt-terephthalic acid) microcapsule membranes was studied as a function of the pH of the medium at different ionic strengths. When the pH of the medium was varied, the permeation rate for 5-sulphosalicylate anions, as well as phenyltrimethylammonium cations, was slow at pH values lower than 4, showed a sudden and large increase in the pH range between 4 and 6, and thereafter remained unchanged. This remarkable change in the permeation rate was found to be produced by an abrupt increase in the microcapsule size observed in the same pH range. Increase in the ionic strength of the medium at pH values higher than 6 increased the rate of anion permeation but decreased the rate of cation permeation due to increase in the screening effect of salt ions on the negative charges in the microcapsule membranes.
研究了电解质离子通过聚（L-赖氨酸-alt-对苯二甲酸）微胶囊膜的渗透情况，该渗透情况是不同离子强度下介质pH值的函数。当介质的pH值变化时，5-磺基水杨酸阴离子以及苯基三甲基铵阳离子的渗透速率在pH值低于4时较慢，在4至6的pH范围内突然大幅增加，此后保持不变。发现这种渗透速率的显著变化是由在相同pH范围内观察到的微胶囊尺寸突然增加所导致的。在pH值高于6时增加介质的离子强度会增加阴离子的渗透速率，但由于盐离子对微胶囊膜中负电荷的屏蔽作用增加，会降低阳离子的渗透速率。
