Electrospun polyvinyl alcohol (PVA)/Chitosan nanofibers were successfully prepared and were used as carriers for the first time in urease immobilization. Also, urease immobilized electrospun PVA/Chitosan nanofibers were applied for the removal of urea from artificial blood serum by recycled reactor. The nanofibers were optimized and synthesized by electrospinning technique according to the operational parameters. The morphology and structure of the nanofibers were characterized by scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis (TGA). Urease was immobilized on the nanofibers by adsorption and crosslinking methods. According to immobilization results, nanofiber enhanced urease stability properties like thermal stability, pH stability, and reusability. Urease immobilized electrospun PVA/Chitosan nanofiber protected its activity by 85% after 10 uses and 45% after 20 uses. Urea removal rates of artificial blood serum were as follows: 100% at 1st cycle, 95% at 2nd, 3rd and 4th cycles; 85% at the 5th cycle; 76% at the 6th cycle, and 65% at the last three cycles.

中文翻译：

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脲酶固定化的静电纺丝PVA /壳聚糖纳米纤维，具有改善的稳定性和可重复使用性：从人造血清中去除尿素的应用。

成功制备了电纺聚乙烯醇（PVA）/壳聚糖纳米纤维，并将其首次用作固定化脲酶的载体。此外，固定化脲酶的静电纺丝PVA /壳聚糖纳米纤维还用于通过循环反应器从人工血清中去除尿素。根据工作参数，通过静电纺丝技术对纳米纤维进行了优化和合成。通过扫描电子显微镜（SEM），衰减全反射-傅立叶变换红外光谱（ATR-FTIR）和热重分析（TGA）表征了纳米纤维的形态和结构。脲酶通过吸附和交联方法固定在纳米纤维上。根据固定化结果，纳米纤维增强了脲酶稳定性，如热稳定性，pH稳定性和可重复使用性。固定有脲酶的静电纺PVA /壳聚糖纳米纤维在10次使用后可保护其活性达85％，20次使用后可保护其活性达45％。人工血清的尿素去除率如下：第一周期为100％，第二，第三和第四周期为95％；第5个周期的85％；第6个周期为76％，最后三个周期为65％。