Non-enzymatic detection of hydrogen peroxide using a functionalized three-dimensional graphene electrode

A novel three-dimensional (3D) electrochemical sensor was developed for highly sensitive detection of hydrogen peroxide (H2O2). Monolithic and macroporous graphene foam grown by chemical vapor deposition (CVD) served as the electrode scaffold. Using in-situ polymerized polydopamine as the linker, the 3D electrode was functionalized with thionine molecules which can efficiently mediate the reduction of H2O2 at close proximity to the electrode surface. Such stable non-enzymatic sensor is able to detect H2O2 with a wide linear range (0.4 to 660 μM), high sensitivity (169.7 μA mM− 1), low detection limit (80 nM), and fast response (reaching 95% of the steady current within 3 s). Furthermore, this sensor was used for real-time detection of dynamic release of H2O2 from live cancer cells in response to a pro-inflammatory stimulant.

Novel non-enzymatic amperometric sensor for H2O2 based on thionine-functionalized 3D graphene electrode via polydopamine linker.Figure optionsDownload as PowerPoint slideHighlights
► Monolithic and macroporous graphene foam serves as 3D electrode scaffold.
► Surface-immobilized thionine efficiently mediates the electrochemical reduction of H2O2.
► Fast and sensitive detection of H2O2 with wide linear range and low detection limit.
► The sensor is used for real-time detection of dynamic release of H2O2 from live cells.