锇聚合物修饰丝网印刷电极的辣根过氧化物酶传感器

Horseradish peroxidase biosensor using electrode modified with osmium polymer

酶生物传感器检测环境污染应用前景良好。该文采用戊二醛-牛血清白蛋白交联法将锇-聚乙烯基吡啶(Os(bpy)2(PVP)10Cl2,Os-PVP)与辣根过氧化物酶(HRP)依次固定在丝网印刷电极上,制备电流型过氧化氢生物传感器。通过循环伏安法对修饰电极的氧化还原性质进行研究,并采用计时-电流法对传感器的固定化和工作参数进行了研究,以便提高信号响应的灵敏度和稳定性。在最适合条件下,底物在修饰电极表面进行催化反应的表观Michaelis-Menten常数kampp为1.79 mmol/L,并确定以HRP酶为标记物的免疫传感器所采用的底物浓度宜大于20倍的kmapp。

Enzyme biosensor has a good application for monitoring environment. Amperometric peroxidase biosensors were prepared using an osmium bipyridyl complex attached to poly （4-vinylpyridine） （Os（bpy）2（PVP）10Cl2, Os-PVP）, and horse radish peroxidase （HRP） immobilized on a screen printed electrode with glutaraldehyde and bovine serum albumin （BSA） by a cross linking reaction. Cyclic voltammetry was used to assess the redox properties of the modified electrodes. Chronoamperometry was used to optimize the HRP biosensor immobilization and working parameters in order to improve the signal response sensitivity and stability. The optimum condition gives an apparent Michaelis-Menten constant （km^app） of 1, 79 mmol/L for the catalytic substrate reaction at the modified electrode, The substrate concentration with HRP as the immuno-sensor marker should be more than 20 times km^app.