In Vivo Electrochemical Detection of Hydrogen Peroxide and Dopamine

Simultaneous analysis of hydrogen peroxide (H2O2) and dopamine (DA) in central nervous system is of great significance and has great challenges. Herein, we reported one ring-disk microelectrode for simultaneous electrochemical analysis of H2O2 and DA. To selectively detect H2O2, the carbon fiber disk (CFdisk) electrode in the middle of the ring-disk microelectrode was electrochemically modified by Prussian blue (PB) and poly(2,3-dihydrothieno-1,4-dioxin) (PEDOT). The Auring on the periphery of the ring-disk microelectrode was used to detect DA. The ring-disk microelectrode exhibited sensitive response to H2O2 (linearity range: 1–29 μM) and DA (linearity range: 0.5–25 μM) with a detection limit of 0.4 μM and 0.18 μM, respectively. The ring-disk microelectrodes were successfully used in measuring H2O2 and DA in vivo. This method provided a new platform for the study of neurophysiology and pathology of H2O2 and DA.