Biosensing Applications of V2O5-CeO2 Mesoporous Silica

Mesoporous silica has been functionalized with vanadium pentoxide (V2O5) and cerium oxide (CeO2). It was then immobilized with biocatalyst horseradish (HRP) to realize highly sensitive detection of H2O2. The electrode was characterized with SEM, cyclic voltammetry, and impedance measurements. A well-defined peak for HRP reduction was noticed at about -0.31V with an apparent heterogeneous electron transfer rate constant of 1.01 s(-1). The catalytic reduction of H2O2 was achieved. The Michaelis constant was calculated to be 0.018 mM. On this electrode, H2O2 was detectable in the range of 20 to 180 mM and the detection limit was 3.0 mM.