中文摘要：

在过氧化氢电化学传感器中，电极起到非常关键的作用。采用溶胶–凝胶法在钛基板上制备了镁掺杂的二氧化钛（Mg–TiO2）纳米点薄膜，并通过电化学还原改时所吸附的酶与基板之间的直接电子传递，改善了纳米点和Ti基板之间的电导率。研究发现：电化学还原处理后纳米点表面的三价钛含量显著增高，有效地提高了直接电子转移；可以增强生物传感器电极的灵敏度。相应的过氧化氢传感器灵敏度达到了1 825.6 μA/（mmolL–1cm2）。电化学还原处理有效地提高了传感器灵敏度。

英文摘要：

Electrodes play a crucial role in hydrogen peroxide （H2O2） electrochemical biosensors. In this paper, Mg-doped TiO2 nanodots were formed on Ti as an electrode substrate by a sol-gel technique. An electrochemical reduction treatment was adopted to improve the direct electron transfer between the working enzyme and the substrate. The results show that Ti3＋ on the surface of Mg-doped TiO2 nanodots clearly increases after the treatment. Biosensors based on such electrodes show a greater response to H2O2, a better direct electron transfer and a greater detection sensitivity. The optimal sensitivity to H2O2 reaches 1825.6 μA/（mmolL-1cm2）. Such a reduction treatment represents a facile and effective route to improve the sensitivity of TiO2 modified biosensor electrodes.