Simultaneous electrochemical detection of dopamine and hydrogen peroxide based on bifunctional microelectrode array

Reactive oxygen species (ROS) and dopamine (DA) can serve as two important biomarkers in the diagnosis of Parkinson’s disease (PD). Due to the close relationship between DA and hydrogen peroxide (H 2 O 2 ) in the process of PD occurrence and development, the simultaneous detection of DA and H 2 O 2 is of great significance for the diagnosis and treatment of PD. In this paper, we report a high integrated bifunctional microelectrode array (MEA) for the simultaneous detection of DA and H 2 O 2 . The sensing electrodes were selectively modified with PEDOT film and Pt-black/PEDOT by electrochemical deposition for detecting DA (with a sensitivity of 38.1 nA/μM/mm 2 ) and H 2 O 2 (with a sensitivity of 45.2 nA/μM/mm 2 ), respectively. The MEA exhibited good sensitivity, selectivity and was capable of sensing both DA and H 2 O 2 simultaneously in serum without any crosstalk. This work proved the feasible of utilizing MEA for multicomponent analysis and showed great potential of MEA for in vitro analysis as well as early diagnosis of PD.