Nano-Molar Level Hydrogen Peroxide Detection by Horseradish Peroxidase Adsorbed Cup-Stacked Carbon Nanotube Electrodes and Applications to L-Glutamate Detection
Nano-Molar Level Hydrogen Peroxide Detection by Horseradish Peroxidase Adsorbed Cup-Stacked Carbon Nanotube Electrodes and Applications to L-Glutamate Detection
复制标题
DOI：
10.2116/analsci.26.675
复制
发表时间：
2010-06-01
影响因子：
1.6
通讯作者：
Yao, Toshio
中科院分区：
文献类型：
--
作者：
Noda, Tatsuo;Ukai, Tadao;Yao, Toshio
我们开发了一种使用叠杯碳纳米管（CSCNT）的高灵敏度直接电子转移型过氧化氢电化学生物传感器的简单制造方法。 CSCNT由杯状碳单元堆叠而成，由于存在含氧官能团（例如-COOH、-OH），因此比多壁碳纳米管（MWCNT）具有更大的内部空间和更亲水的边缘。当CSCNTs悬浮液被浇注时，CSCNTs均匀地分散在玻碳（GC）电极上，并且辣根过氧化物酶（HRP）通过物理吸附牢固地固定，没有任何化学反应。采用HRP/CSCNTs/GC电极的流动注射分析(FIA)系统比HRP/MWCNTs/GC电极具有优越的灵敏度和稳定性。检测限为0.75 nM (S/N = 3)，活性在21天内保持在85%以上。此外，当将谷氨酸氧化酶（GIOD）固定化反应器设置到所提出的 FIA 系统中时，可以重复检测 L-谷氨酸，检测限为 1.2 nM（S/N = 3）。
We have developed a simple fabrication method of a highly sensitive direct electron transfer-type electrochemical biosensor for hydrogen peroxide by use of cup-stacked carbon nanotubes (CSCNTs). The CSCNTs, formed by stacking of cup-shaped carbon units, has larger internal space and more hydrophilic edges, thanks to the presence of functional groups containing oxygen (e.g., -COOH, -OH), than multi-walled carbon nanotubes (MWCNTs). When the CSCNTs suspension was cast, the CSCNTs were dispersed homogeneously onto a glassy carbon (GC) electrode, and horseradish peroxidase (HRP) was immobilized firmly by physical adsorption without any chemical reactions. The flow injection analysis (FIA) system with the HRP/CSCNTs/GC electrode has superior sensitivity and stability to the HRP/MWCNTs/GC electrode. The detection limit was 0.75 nM (S/N = 3) and the activity was maintained over 85% for 21 days. Further, when the glutamate oxidase (GIOD)-immobilized reactor was set into the proposed FIA system, L-glutamate could be detected repeatedly with a detection limit of 1.2 nM (S/N = 3).