摘要
在金盘电极表面制备L-半胱氨酸（L-Cys）自组装单分子膜，通过调节溶液的酸度使辣根过氧化物酶（HRP）带有正电荷，利用控制电位的方法在L-Cys自组装单分子膜上组装HRP，制备出辣根过氧化物酶／L-半胱氨酸／金电极（HRP／L-Cys／Au），进而研究金表面上固定化HRP的电化学表征方法以及对H2O2的催化还原作用。结果表明，该固定方法能很好地保持酶的催化活性，能有效催化H2O2分解，所制备的HRP／L—Cys／Au电极在2．2×10^-5～2．2×10^-2mol／L范围内，还原峰电流与H2O2的浓度呈良好线性关系，相关系数为0．996，对H2O2的检测下限为2．2×10^-5mol／L，本文为生物分子的固定化提供了一种较好的方法，对生物传感器的研究具有重要意义。
The immobilization of horseradish peroxidase （HRP） on gold electrode modified with L-cysteine self-assembled monolayer （SAM） has been investigated by electrochemistry. A cleaned gold electrode was first immersed in L-cysteine solution,and then the acidity of HRP solution was adjusted by the phosphate buffer solution for making HRP with positive charge. Finally, HRP was immobilized on the L-cysteine SAM by potential control. The horseradish peroxidase/L-cysteine/ gold electrodes （HRP/L-Cys/Au） were prepared and characterized with cyclic voltammetry. The enzymic response of the HRP/L-Cys/Au electrodes to reduction of H2O2 was investigated by amperometry. The results indicated that the immobilized HRP still retained a high bioactivity on this electrode material. The electrode displayed excellent enzymic response to the reduction of H2O2 and the detection limit of H2O2 was 2.2 × 10^ -5 mol/L. The immobilization is of great significance for preparing biosensor.
出处
《世界科技研究与发展》
CSCD
2007年第2期27-30,共4页
World Sci-Tech R&D
基金
国家自然科学基金(60572009)
辽宁省科技厅自然科学基金(99102004)资助项目
