Amperometric Biosensor for Hydrogen Peroxide Based on Electrodeposited Sub-micrometer Gold Modified Glassy Carbon Electrode

• 来源期刊: 中国化学（英文版）
• 学科: 化学
• 年，卷（期）: 2004,（4）
• 页码范围: 360-364
• 页数: 5页
• 分类号: O6
• 语种: 英文

摘要

A new type of hydrogen peroxide amperometric biosensor was fabricated based on electrochemically deposited sub-micrometer Au particles(sm-Au)on a glassy carbon electrode(GCE).Electrochemical deposition condition was optimized for obtaining uniformly distributed sub-micrometer sized Au array on the electrode surface.The hydrogen peroxide sensor was fabricated by adsorbing phenothiazine methylene blue(MB)molecules on the surface of sm-Au and covering a cross-linked horseradish peroxidase(HRP)layer,labeled as HRP/MB/sm-Au/GCE.The characteristics of this biosensor were evaluated with respect to applied potential and pH.The amperometric response of the sensor was linear to the H2O2 concentration over a wide range of 9.9×10-6-1.11×10-2 mol/L.A detection limit(s/n＝3)of 3.0×10-6 mol/L H2O2 was estimated for a sampled chronoamperometric detection at 1.5 min after potential step of 200 to-400 mV vs.SCE.The immobilized MB molecules shuttled electrons at(＝0.77 and an apparent electron transfer rate constant of ＝0.053 s-1.Interference of ascorbic acid,dopamine and uric acid was investigated.This sensor has very good stability and reproducibility for long-term use.