(1. 湖南大学 环境科学与工程学院，长沙 410082；2. 湖南城市学院 化学与环境工程学院，益阳 413000；3. 湖南大学 环境生物与控制教育部重点实验室，长沙 410082)
摘 要: 采用分子自组装技术制备巯基修饰的基因分子膜修饰金电极，用于竞争式杂交检测黄孢原毛平革菌木素过氧化物酶编码基因。通过差分脉冲伏安法、循环伏安法、交流阻抗法和电流—时间曲线法优化自组装时间和信号探针的最佳响应浓度，研究目标基因的线性检测范围和再生性能。结果表明：修饰金电极最优自组装时间为15 h，信号探针的最佳响应浓度为0.51×10-6 mol/L，目标基因的线性检测范围为7.51×10-12~1.05×10-9 mol/L，检测下限为7.51×10-13 mol/L。该修饰电极具有良好的再生性能。
关键字: 修饰金电极；自组装单分子膜；基因；竞争杂交；电化学检测
（1. College of Environmental Science and Engineering, Hunan University, Changsha 410082, China;2. College of Chemistry and Environmental Engineering, Hunan City University, Yiyang 413000, China;3. Key Laboratory of Environmental Biology and Pollution Control (Hunan University),Ministry of Education, Changsha 410082, China）
Abstract:A gold electrode with thiolated capture probe through self-assembling based on the competitive hybridization for detection of target sequence of lignin peroxidase (lip) gene of Phanerochaete chrysosporium was developed. Following hybridizations with competitively hybridized with the target nucleic acid and biotinylated response probe, streptavidin-horseradish peroxidase (HRP) conjugate was applied to the electrode. The electrochemical behavior was analyzed by cyclic voltammetry, electrochemical impedance spectroscopy, current—time curve and differential pulse voltammetry. The results show that the best time for self-assembling is 15 h, and the optimum concentration of response probe is 0.51×10-6 mol/L. A good linear correlation between the current and the concentration of the target nucleic acid concentration is found in the concentration range from 7.51×10-12 mol/L to 1.05×10-9 mol/L. The detection limit is 7.51×10-13 mol/L. The modified electrode exhibits high sensitivity, precision, stability and reproducibility.
Key words: modified gold electrode; self-assembled monolayer; gene; competitive hybridization; electrochemical determination
