Silver doped mesoporous silica nanoparticles based electrochemical enzyme-less sensor for determination of H 2 O 2 released from live cells

Abstract

In this study, a silver doped mesoporous silica nanoparticles-based enzyme-less electrochemical sensor for the determination of hydrogen peroxide (H 2 O 2 ) released from live cells was constructed for the first time. The presented electrochemical sensor exhibited fast response (2 s) towards the reduction of H 2 O 2 concentration variation at an optimized potential of 􀀀0.5 V with high selectivity over biological interferents such as uric acid, ascorbic acid, and glucose. In addition, a wide linear range (4 μM to 10 mM) with a low detection limit (LOD) of 3 μM was obtained. Furthermore, the Ag-mSiO 2 nanoparticles/glass carbon electrode (Ag-mSiO 2 NPs/GCE) based enzyme-less sensor showed good electrocatalytic performance, as well as good reproducibility, and long-term stability, which provided a successful way to in situ determine H 2 O 2 released from live cells. It may also be promising to monitor the effect of reactive oxygen species (ROS) production in bacteria against oxidants and antibiotics.