Department of Chemistry, Razi University, Kermanshah, Iran.
Bioelectrochemistry. 2012 Feb;83:31-7. doi: 10.1016/j.bioelechem.2011.08.003. Epub 2011 Aug 16.
A robust and effective nanocomposite film-glassy carbon modified electrode based on multi-walled carbon nanotubes and a room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was prepared by a layer-by-layer self-assembly method. The fabricated modified electrode was used as a novel impedimetric catalase nanobiosensor for the determination of H(2)O(2). Direct electron transfer and electrocatalysis of catalase were fully investigated. The results suggested that catalase could be firmly adsorbed at the modified electrode. A pair of quasi-reversible redox peaks of catalase was observed in a 0.20 M degassed phosphate buffer solution of pH 7.0. The nanocomposite film showed a pronounced increase in direct electron transfer between catalase and the electrode. The immobilized catalase exhibited an excellent electrocatalytic activity towards the reduction of H(2)O(2). The electrochemical impedance spectroscopy measurements revealed that the charge transfer resistance decreases significantly after enzymatic reaction with hydrogen peroxide, so that the prepared modified electrode can be used for the detection of ultra traces of H(2)O(2) (5-1700 nM).
一种基于多壁碳纳米管和室温离子液体 1-丁基-3-甲基咪唑六氟磷酸盐的坚固有效的纳米复合膜-玻碳修饰电极，通过层层自组装方法制备。所制备的修饰电极可用作新型的酶促过氧化氢纳米生物传感器，用于测定 H（2）O（2）。对过氧化氢酶的直接电子转移和电催化作用进行了充分研究。结果表明，过氧化氢酶可以在修饰电极上牢固地吸附。在 0.20 M 脱气磷酸盐缓冲溶液（pH 7.0）中观察到过氧化氢酶的一对准可逆氧化还原峰。纳米复合膜显示出酶与电极之间直接电子转移的显著增加。固定化的过氧化氢酶对 H（2）O（2）的还原表现出优异的电催化活性。电化学阻抗谱测量表明，酶促反应后过氧化氢的电荷转移电阻显著降低，因此，所制备的修饰电极可用于检测痕量的 H（2）O（2）（5-1700 nM）。
