摘要
采用壳聚糖包裹的多壁碳纳米管膜固定辣根过氧化物酶（HRP）于玻碳电极表面，实现了HRP的直接电化学并以此酶膜制备了NO生物传感器。在磷酸缓冲溶液中固定在电极表面的HRP氧化还原式电位为-0．354V（vs．SCE），直接电子转移速率常数为4．24±1．02s^-1。研究结果表明，固定在电极表面的HRP能保持其对一氧化氮还原的生物电催化活性，该传感器在NO浓度为1．0×10^-4～1．4×10^-3molL^-1范围内存在线性响应，响应时间小于11s，NO的检出限为7×10^-4molL^-1。多壁碳纳米管特殊的电学性质和壳聚糖良好的生物相容性性使得构筑的HRP生物传感器呈现了良好的应用前景，尤其适用于痕量NO的检测。
Horseradish peroxidase （HRP） was immobilized onto chitosan wrapped multiwalled carbon nanotubes （MWCNTs） for the construction of a bioelectrochemical platform for direct electrochemistry and biosensing purposes. The direct electron transfer between HRP and the electrode surface was observed with a formal potential of about - 0.354 V （vs. SCE） in phosphate buffer solution and the calculated heterogeneous electron transfer rate constant is about 4.24 ± 1.02 s^-1 Experimental results confirmed that the immobilized HRP retains its catalytic activity toward the reduction of nitrite. Such an HRP - MWCNTs - chitosan based biosensor exhibited a rapid response time of less than 11 s and a good linear range from 1.0 × 10^-4 to 1.4 × 10^-3 mol L^-1 with a detection limit of 7 × 10^-4 mol L^-1 for the nitric oxide detection. Both the unique electrical properties of MWCNTs and the biocompatibility of chitosan enable us to construct an excellent biosensing platform for improving electrocatalysis of HRP, especially for the detection of trace of nitric oxide.
出处
《功能材料与器件学报》
CAS
CSCD
北大核心
2008年第6期1035-1038,共4页
Journal of Functional Materials and Devices
基金
江苏省教育厅高校自然科学基金(01KJB150004)
