Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, PR China.
Biosens Bioelectron. 2013 May 15;43:131-6. doi: 10.1016/j.bios.2012.11.040. Epub 2012 Dec 13.
A glucose biosensor based on direct electron transfer of glucose oxidase (GOD) self-assembled on the surface of the electrochemically reduced carboxyl graphene (ERCGr) modified glassy carbon electrode has been reported. X-ray photoelectron spectroscopy (XPS) analyses of ERCGr indicate most of the oxygen-containing groups such as epoxy/ether groups and hydroxyl groups in the carboxyl graphene were eliminated, while carboxylic acid groups remained. GOD was immobilized on the ERCGr modified glassy carbon electrode via self-assembly. The cyclic voltammetric result of the electrode shows a pair of well-defined and quasi-reversible redox peaks with a formal potential of -0.467 V and a peak to peak separation of 49 mV, revealing that the direct electron transfer between GOD and the electrode has been achieved. The proposed biosensor exhibits a linear response to glucose concentrations ranging from 2 to 18 mM with a detection limit of 0.02 mM. Moreover, this facile, fast, environment-friendly and economical preparation strategy of ERCGr may be extended for the preparation of other graphene based enzyme electrode biosensors.
基于葡萄糖氧化酶（GOD）在电化学还原的羧基石墨烯（ERCGr）修饰玻碳电极表面自组装实现的直接电子转移的葡萄糖生物传感器已经被报道。ERCGr 的 X 射线光电子能谱（XPS）分析表明，羧基石墨烯中的大部分含氧基团，如环氧/醚基团和羟基，都被消除了，而羧酸基团仍然存在。GOD 通过自组装固定在 ERCGr 修饰的玻碳电极上。电极的循环伏安结果显示出一对定义良好且近乎可逆的氧化还原峰，具有 -0.467 V 的形式电位和 49 mV 的峰-峰分离，表明 GOD 和电极之间已经实现了直接电子转移。所提出的生物传感器对葡萄糖浓度在 2 至 18 mM 范围内呈现出线性响应，检测限为 0.02 mM。此外，这种简便、快速、环保和经济的 ERCGr 制备策略可能会扩展到其他基于石墨烯的酶电极生物传感器的制备中。
