Department of Chemistry, Kyungpook National University, Daegu, South Korea.
Biosens Bioelectron. 2009 Dec 15;25(4):944-7. doi: 10.1016/j.bios.2009.08.041. Epub 2009 Sep 1.
A three dimensional network comprising of covalently linked multi-walled carbon nanotubes (MWNT), silica and polyaniline chains (MWNT-Silica-PANI-NW) was prepared and used as the matrix for immobilization of an enzyme (horseradish peroxidase, HRP). MWNT-Silica-PANI-NW-HRP electrode showed superior performances over the individual components and their binary combinations, in terms of enzyme stability (minimum leaching to the medium), fast electron transfer from the enzyme to the electrode (2.11s(-1)), high sensitivity (58.1microAmM(-1)) and low detection limit (1pM) for the detection of hydrogen peroxide. The interconnected silica network provides open porous frame work for effective immobilization of the redox enzyme. The PANI units and MWNTs facilitate the electron transfer process and functions as molecular cable to "wire" the primary redox site of the enzyme (HRP) to the electrode. The improved performances for MWNT-Silica-PANI-NW arise from the synergistic contributions from conducting CNT, electron mediating PANI chains and porous silica network.
一种由共价键连接的多壁碳纳米管（MWNT）、二氧化硅和聚苯胺链（MWNT-Silica-PANI-NW）组成的三维网络被制备出来，并用作固定酶（辣根过氧化物酶，HRP）的基质。MWNT-Silica-PANI-NW-HRP 电极在酶稳定性（最小浸出到介质中）、酶到电极的快速电子转移（2.11s(-1)）、高灵敏度（58.1μM(-1)）和低检测限（1pM）方面表现出优于单个组件及其二元组合的性能，用于检测过氧化氢。互联的二氧化硅网络为氧化还原酶的有效固定提供了开放的多孔框架。PANI 单元和 MWNTs 促进了电子转移过程，并作为分子电缆将酶（HRP）的主要氧化还原位点连接到电极上。MWNT-Silica-PANI-NW 的性能得到改善，是由于导电 CNT、电子中介 PANI 链和多孔二氧化硅网络的协同贡献。
