Two-Dimensional Ordered Silicon Dioxide Cavities Array as Matrix for the Immobilization of Horseradish Peroxidase and Its Direct Electrochemistry

A silicon dioxide (SiO2) cavities array was fabricated on indium-tin oxide (ITO) electrode with polystyrene (PS) particles array as template by using sol-gel technique. The electrochemical properties of SiO2 cavities array indicated that it acted as microelectrode array. Horseradish peroxidase (HRP) was immobilized on the surface of SiO2 cavities by adsorption method. Direct electrochemistry of HRP modified SiO2 cavities array was studied. The results showed that the microenvironment of SiO2 cavities can accelerate electron transfer of HRP efficiently and the electron transfer rate was calculated to be 1.98 s(-1).