Deng Chunyan, Chen Jinhua, Chen Xiaoli, Xiao Chunhui, Nie Lihua, Yao Shouzhuo
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, PR China.
Biosens Bioelectron. 2008 Mar 14;23(8):1272-7. doi: 10.1016/j.bios.2007.11.009. Epub 2007 Nov 28.
Due to their unique physicochemical properties, doped carbon nanotubes are now extremely attractive and important nanomaterials in bioanalytical applications. In this work, selecting glucose oxidase (GOD) as a model enzyme, we investigated the direct electrochemistry of GOD based on the B-doped carbon nanotubes/glassy carbon (BCNTs/GC) electrode with cyclic voltammetry. A pair of well-defined, quasi-reversible redox peaks of the immobilized GOD was observed at the BCNTs based enzyme electrode in 0.1M phosphate buffer solution (pH 6.98) by direct electron transfer between the protein and the electrode. As a new platform in glucose analysis, the new glucose biosensor based on the BCNTs/GC electrode has a sensitivity of 111.57 microA mM(-1)cm(-2), a linear range from 0.05 to 0.3mM and a detection limit of 0.01mM (S/N=3). Furthermore, the BCNTs modified electrode exhibits good stability and excellent anti-interferent ability to the commonly co-existed uric acid and ascorbic acid. These indicate that boron-doped carbon nanotubes are the good candidate material for the direct electrochemistry of the redox-active enzyme and the construction of the related enzyme biosensors.
由于其独特的物理化学性质，掺杂碳纳米管如今在生物分析应用中是极具吸引力且重要的纳米材料。在本工作中，我们选择葡萄糖氧化酶（GOD）作为模型酶，采用循环伏安法研究了基于硼掺杂碳纳米管/玻碳（BCNTs/GC）电极的GOD直接电化学。在0.1M磷酸盐缓冲溶液（pH 6.98）中，通过蛋白质与电极之间的直接电子转移，在基于BCNTs的酶电极上观察到固定化GOD的一对定义明确的准可逆氧化还原峰。作为葡萄糖分析的新平台，基于BCNTs/GC电极的新型葡萄糖生物传感器灵敏度为111.57 μA mM⁻¹ cm⁻²，线性范围为0.05至0.3 mM，检测限为0.01 mM（S/N = 3）。此外，BCNTs修饰电极对常见共存的尿酸和抗坏血酸表现出良好的稳定性和出色的抗干扰能力。这些表明硼掺杂碳纳米管是氧化还原活性酶直接电化学及相关酶生物传感器构建的良好候选材料。
