Effect of nanometer particles on the adsorbability and enzymatic activity of glucose oxidase

In this paper, hydrophilic gold and hydrophobic silica nanometer particles of different sizes were added to a glucose oxidase (GOD) membrane to improve the enzymatic activity. The enzymatic electrodes were platinum electrodes covered with a membrane containing GOD and particles. Comparing the response current of these electrodes, it has been found that both hydrophobic SiO2 and hydrophilic Au can improve the enzymatic activity of the GOD membrane. Electrodes containing 30 nm SiO2 particles had higher sensitivity than those containing 30 nm Au particles. In the case of 10 nm particles, the situation was different, although both types of electrode showed greater currents as the particle size became smaller, electrodes containing Au particles possessed much higher sensitivity than those containing SiO2 particles. The mechanism of this phenomenon has been studied and is discussed on the basis of adsorption of GOD on ultrafine particles.