Thermocontrolling Ion Permeation Through BinaryComponent Membrane Composed of Crown Ether Liquid Crystal/PVC
Jun Qin, Minggui Xie, Qing Jiang, Huaming Zhao Shengchong Liu and Changyuan Tao(Department of Chemistry, Third Military Medical College, Chongqing 630038, China)(Department of Chemistry, Sichuan University, Chengdu 610064, China) (Analytical and Testing C
In view of the nature of orderness in structure and the menomorphism in property of liquid crystal, the function of which is further exploited by integrating it with the feature of crown ether. The rnonoarmed crown ether liquid crystals are successfully applied to the imitation of biomembrane transport. Binary component membrane composed of crown ether liquid crystal and PVC was first developed. Such a novel model of biomimetic membrane is capable of imitating ingeniously the thermocontrolling transport of biomembrane, thus the essential function of liquid crystal in membane transport is more fully exploited. It was suggested, consequently, that the molecules of the crown ether crystal could assemble themselves to form ionic chanels, as they exist in mesophase.Of still more significance is that the thermocontrolling transport of ions through the membrane is found to be operative selectively and the permeation of ion is under the direct influence of the thernal turmoil of the crown ether liquid crystal molecules as substantiated by the values of Arrhenius thermodynarnic parameters, activation energy, Ea, and logarithmic Arrhenius constant, logA, in ion transport. Based on the aforementioned it is suggested that diffusion of ions is a rate-determing step and change of rate of ion transport is varied in different phases. Influence of magnetic field on transport rate is investigated. On basis of above experimental findings, a dynamical equation of ion transportation is established which is applicable for the membrane system in general on one hand and expounds the ion transport mechanism through the membrane on the other.