Abstract：
The study examines the immobilization of the urease enzyme on a range of High Internal Phase Emulsion (polyHIPE) materials, assessing characteristics, efficiency, and performance. It also investigates the impact of polyHIPE type, quantity, incubation time, and various parameters on the process and enzyme activity. Surface morphology and functional groups of polyHIPE materials were determined through scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FT-IR) analyses, revealing significant alterations after modification with polyglutaraldehyde (PGA). The maximum immobilization efficiency of 95% was achieved by adding PGA to polyHIPE materials with an incubation period of 15 h. The optimized conditions for immobilized enzyme using a Box-Behnken design (BBD) of response surface methodology (RSM) were as follows: temperature (40.8 °C), pH (7.1) and NaCl concentration (0.007 g/L). Furthermore, the immobilized enzyme demonstrated remarkable reusability, retaining 75% of its initial activity after six cycles, and sustained shelf-life stability, retaining over 40% activity after 10 days at room temperature. Kinetic analyses revealed that immobilized urease exhibited higher affinity for the substrate, but lower rate of substrate conversion compared to the free enzyme. These findings offer valuable insights into optimizing urease immobilization processes and enhancing urease stability and activity, with potential applications in various fields, including biotechnology and biocatalysis.
摘要：
该研究检查了脲酶在一系列高内相乳液（polyHIPE）材料上的固定化，评估特征，效率,和性能。它还调查了polyHIPE类型的影响，数量,孵化时间,以及过程和酶活性的各种参数。通过扫描电子显微镜(SEM)和傅里叶变换红外光谱(FT-IR)分析测定了聚HIPE材料的表面形貌和官能团,显示用聚戊二醛（PGA）修饰后的显着变化。通过将PGA添加到聚HIPE材料中，孵育时间为15小时，可实现95％的最大固定效率。使用响应面方法（RSM）的Box-Behnken设计（BBD）的固定化酶的优化条件如下：温度（40.8°C），pH(7.1)和NaCl浓度(0.007g/L)。此外，固定化酶表现出显著的可重用性，在六个周期后保留其初始活性的75％，和持续的保质期稳定性，在室温下10天后保留超过40%的活性。动力学分析表明，固定化脲酶对底物表现出更高的亲和力，但与游离酶相比，底物转化率较低。这些发现为优化脲酶固定化过程和增强脲酶稳定性和活性提供了宝贵的见解。在各个领域的潜在应用，包括生物技术和生物催化。
