CONTROL OF ENZYME ACTIVITY BY ECOSENSITIVE POLYMER GEL

1. 研究了凝胶的物理化学结构及其动力学行为，以不同组成的主单体（n -异丙基丙烯酰胺）和交联单体合成了热敏聚合物水凝胶。基于平均场理论，分析了网络在各种热波动下的动力学行为与网络扩散系数的相关关系。凝胶的动态行为（膨胀和收缩率）很大程度上取决于凝胶的物理结构。膨胀的速度取决于凝胶网络的扩散。收缩速度可以通过热操作来控制。主单体含量小、交联程度小的凝胶，由于凝胶表面形成致密的皮层，反应速度极慢。凝胶的动力学行为和固定化酶的活性研究了热刺激（热摇摆）对热响应性n -异丙基丙烯酰胺凝胶中固定化酶相对活性的影响。固定化酶的相对活性受温度控制。基质和产物的传质受凝胶网络孔径的控制。通过热振荡使凝胶反复膨胀和收缩，提高了固定化酶的相对活性。以下因素可有效控制酶的相对活性。(1)膨胀度，(2)收缩时间，(3)膨胀收缩速率（凝胶网络的扩散速率），由此得出(1)大体积位移快速反应凝胶的分子设计和(2)快速反应的热操作的指导方针

1. PHYSICOCHEMICAL STRUCTURE OF GEL AND ITS DYNAMIC BEHAVIORTHE THERMORESPONSIVE POLYMER HYDROGEL WERE SYNTHESIZED WITH VARIOUS COMPOSITION OF MAIN MONOMER (N-ISOPROPYLACRYLAMIDE) AND CROSSLINKING MONOMER.THE DYNAMIC BEHAVIORS IN RESPONSE TO VARIOUS THERMAL SWING WERE CORELATED WITH DIFFUSION COEFFICIENT OF THE NETWORK BASED ON THE MEAN FIELD THEORY.THE DYNAMIC BEHAVIOR (SWELLING AND SHIRINKING RATE) DEPENDED STRONGLY ON THE PHYSICAL STRUCTURE OF THE GEL.THE RATE OF SWELLING DEPENDS ON THE DIFFUTION OF THE GEL NETWORK.THE RATE OF SHRINKING CAN BE CONTROLLED BY THERMAL OPERATION.THE GEL WITH SMALL MAIN MONOMER CONTENT AND SMALL DEGREE OF CROSSLINKING SHOWS EXTREAMLY SLOW RESPONSE DUE TO A FORMAITON OF DENSE SKIN LAYER ON THE SURFACE OF THE GEL.2. DYNAMIC BEHAVIOR OF THE GEL AND ACTIVITY OF IMMOBILIZED ENZYMETHE EFFECT OF THERMAL STIMULUS (THERMAL SWING) ON THE RELATIVE ACTIVITY OF ENZYME IMMOBILIZED IN THERMORESPONSIVE N-ISOPROPYLACRYLAMIDE GEL WAS STUDIED.THE RELATIVE ACTIVITY OF IMMOBILIZED ENZYME WAS CONTROLLED BY TEMPERATURE.THE MASS TRANSFER OF SUBSTRATE AND PRODUCT WAS CONTROLLED BY THE PORE SIZE OF THE GEL NETWORK.THE RELATIVE ACTIVITY OF THE IMMOBILIZED ENZYME WAS INCREASED BY REPEATING SWELLING AND SHRINKING OF THE GEL THROUGH THERMAL SWING.THE FOLLOWING FACTORS WERE FOUND TO BE EFFECTIVE TO CONTORL THE RELATIVE ACTIVITY OF THE ENZYME.(1) DEGREE OF SWELLING,(2) TIME OF SHIRINKING,(3) RATE OF SWELLING AND SHRINKING (THE RATE OF DIFFUTION OF THE GEL NETWORK)FROM THESE RESULTS,THE GUIDE LINE FOR (1) THE MOLECULAR DESIGN OF THE GEL WITH LARAGE VOLUME DISPLASEMENT AND QUICK RESPONSE AND (2) THERMAL OPERATION FOR QUICK RESPONSE WERE OBTAINED