ION AND ELECTRON TRANSPORT ACROSS ENZYME IMMOBILIZED BIPOLAR MEMBRANE

包括电子在内的物质在膜上的流动是由电化学电位的差异、其他物质的流动和化学反应引起的。众所周知，如果系统由对称结构组成，由于化学反应是标量的，所以不应该有流动与化学反应耦合。然而，如果系统的结构是非对称的，则Lt可能是耦合的。研究了一种酶固定化双极膜，该双极膜具有不对称结构，由膜两侧带正电层和带负电层组成，膜层之间含有酶。以尿素-脲酶体系为研究对象，探讨了转运与化学反应的耦合机理。在分析过程中，我们发现弱电解质在带电膜上的传输机制在理论上和实验上都还没有系统化。为了澄清这些问题，我们首先研究了膜外溶液浓度对Na_2SO_3渗透系数的影响。其次，考虑到Na_2SO_3渗透的结果，从理论上研究了弱电解质在带电膜上的输运现象，其中解离平衡常数必须包含在方程中。理论结果定性地解释了输运与化学反应的耦合现象。

The substance flow including electron across a membrane is induced by the difference of electrochemical potential, the flow of other substances and the chemical reaction. It is well known that no flow should be coupled with chemical reaction if the system is composed of symmetric structure because chemical reaction is scalar. lt,however,could be coupled if the structure of the system is asymmetric.An enzyme-immobilized bipolar membrane, which has an asymmetric structure consisting of positively and negatively charged layers on each side of the membrane and is containing enzyme between them, was studied. The coupling mechanism of the transport and chemical reaction was discussed using urea-urease system. In course of this analysis, we found that the transport mechanism of weak electrolyte across charged membrane was not systematized yet theoretically and experimentally. To clarify these problems we firstly investigate the permeability coefficients of Na_2SO_3 as a function of concentration of external solution of the membrane. Secondary the transport phenomena of weak electrolyte across charged membrane are investigated theoretically considering the result of Na_2SO_3 permeation, where the dissociation equilibrium constant has to be included in the equation. The theoretical results well explained coupling phenomena of transport and chemical reaction qualitatively.