Tahsiri Z, Niakousari M, Niakowsari A
Department of Food Science and Technology, College of Agriculture, Shiraz University, Shiraz, Iran.
Departments of Communication and Electronics, School of Computer and Electrical Engineering, Shiraz University, Shiraz, Iran.
Heliyon. 2023 Jun 2;9(6):e16971. doi: 10.1016/j.heliyon.2023.e16971. eCollection 2023 Jun.
In the present study, we aimed to develop a fast, non-toxic ultrasonic-assisted technique for the preparation of graphene oxide (GO) and GO that were accessorized with FeO (GO-FeO) for enzyme immobilization. The structural properties of nanosheets were determined by FTIR, XRD, and SEM. Immobilized enzymes on the GO-FeO and GO were counted. Enzyme activity, reusability, and improvements in enzyme stability were studied. According to the results, the immobilization efficiency was 256.86 mg ficin/GO (g), and 253.63 mg ficin/GO-FeO (g). Furthermore, immobilized ficin was affected in terms of stability by variations in pH and temperature. The immobilized ficin on the GO-FeO could be easily recycled from the reaction medium by applying external magnetic separation, involving 10 cycles for 120 days. Over this period and with this number of cycles, the immobilized enzyme on the GO-FeO retained 74% of its original activity, whereas the immobilized enzyme on the GO was recycled from the reaction medium after centrifuging, thereby retaining 70% of its original activity. Thus, GO and GO-FeO nanosheets were obtained efficiently from the ultrasonic-assisted technique and can be regarded as excellent nanocarriers for enzyme immobilization.
在本研究中，我们旨在开发一种快速、无毒的超声辅助技术，用于制备氧化石墨烯（GO）以及用FeO修饰的氧化石墨烯（GO-FeO）以用于酶固定化。通过傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）和扫描电子显微镜（SEM）来测定纳米片的结构性质。对固定在GO-FeO和GO上的酶进行计数。研究了酶活性、可重复使用性以及酶稳定性的提高情况。根据结果，固定化效率为256.86毫克无花果蛋白酶/GO（克）和253.63毫克无花果蛋白酶/GO-FeO（克）。此外，固定化的无花果蛋白酶在稳定性方面受pH值和温度变化的影响。通过外部磁分离，GO-FeO上固定化的无花果蛋白酶可轻松从反应介质中回收，在120天内可循环使用10次。在此期间和此循环次数下，GO-FeO上固定化的酶保留了其原始活性的74%，而GO上固定化的酶通过离心从反应介质中回收，从而保留了其原始活性的70%。因此，通过超声辅助技术可高效获得GO和GO-FeO纳米片，它们可被视为用于酶固定化的优良纳米载体。
