SiO_2球腔微电极阵列过氧化氢传感器制备及应用

Preparation and Application of Hydrogen Dioxide Biosensor Based on Microelectrode Array of SiO_2 Cavity

将微过氧化物酶-11(MP-11)直接固定于二氧化硅球腔微电极阵列,制备一种新型电化学过氧化氢(H2O2)生物传感器。采用Langmuir-Blodgett技术在氧化铟锡(ITO)电极表面制备聚苯乙烯(PS)微球阵列,并以此阵列为模板采用溶胶-凝胶法在ITO电极上制备二氧化硅(SiO2)球腔阵列,最后将微过氧化物酶-11作为氧化还原模型蛋白直接吸附于球腔内,制得MP-11/SiO2球腔阵列/ITO电极。该电极对H2O2响应快速灵敏,可作为电流型H2O2电化学生物传感器,其线性范围为7.06×10-6～4.02×10-2mol/L,检出限为3.0×10-7mol/L,米氏常数为0.916mmol/L。将该法用于食品样品中的H2O2的检测,回收率在94%～97%之间,效果良好,可为食品中残存的H2O2检测提供一种方法。

A new biosensor for the detection of H202 was prepared by immobilizing microperoxidase-11 （MP-11） onto silicon dioxide （SiO2） cavity array directly. Polystyrene （PS） particle array was constructed on indium-tin oxide （ITO） electrode surface by Langrnuir-Blodgett technique. The silicon dioxide cavity array was prepared by Langmuir-Blodgett technique using PS particle array as the template. Using MP-11 as a model protein, MP-11/SiO2 cavity array-ITO electrode was prepared by adsorbing MP-11 into SiO2 cavity. The fast response of the biosensor against H2O2 was observed. A linear relationship between current response and H2O2 concentration ranging from 7.06 × 10-6 to 4.02 × 10.2 mol/L was achieved with a detection limit of 3.0 ×107 mol/L. The apparent Michaelis-Menten constant was 0.916 mmol/L. This established method is satisfactory for the determination of hydrogen peroxide in food samples with a recovery rate varying from 94% to 97%.