Department of Nanobiotechnology, Faculty of Biological Science, Tarbiat Modares University, Tehran, Iran.
Int J Biol Macromol. 2012 May 1;50(4):1063-9. doi: 10.1016/j.ijbiomac.2011.12.025. Epub 2012 Jan 16.
Silica-encapsulated magnetic nanoparticles (MNPs) were prepared via microemulsion method. The products were characterized by high resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectrum (EDS). MNPs with no observed cytotoxic activity against human lung carcinoma cell and brine shrimp lethality were used as suitable support for glucose oxidase (GOD) immobilization. Binding of GOD onto the support was confirmed by the FTIR spectra. The amount of immobilized GODs was 95 mg/g. Storage stability study showed that the immobilized GOD retained 98% of its initial activity after 45 days and 90% of the activity was also remained after 12 repeated uses. Considerable enhancements in thermal stabilities were observed for the immobilized GOD at elevated temperatures up to 80°C and the activity of immobilized enzyme was less sensitive to pH changes in solution.
采用微乳液法制备了二氧化硅包裹的磁性纳米颗粒（MNPs）。通过高分辨率透射电子显微镜（HRTEM）和能谱（EDS）对产物进行了表征。MNPs 对人肺癌细胞无明显细胞毒性，对卤虫致死率无影响，可用作葡萄糖氧化酶（GOD）固定化的合适载体。FTIR 光谱证实了 GOD 结合到载体上。固定化 GOD 的量为 95mg/g。储存稳定性研究表明，固定化 GOD 在 45 天后保留了初始活性的 98%，在 12 次重复使用后仍保留了 90%的活性。固定化 GOD 在高达 80°C 的高温下表现出显著的热稳定性增强，并且固定化酶的活性对溶液 pH 值的变化不太敏感。
