Electrochemical dopamine biosensor using over-oxidized polypyrrole with assistance of graphene
Abstract
This paper described a disposable overoxidized polypyrrole/graphene/gold (OPPy/GE/Au) microelectrode by two-step electrooxidation at a three-electrode-integrated electrochemical sensor, and its application for selective determination of dopamine (DA) without the interference of ascorbic acid (AA). Compared with the bare Au electrode, OPPy/GE/Au electrode exhibits much stronger electroactivity for DA, as well as intense electrostatic inhibition towards the oxidation of AA at the same time. Such a compatible with mass production and low-cost fabrication of on-chip DA sensor presented a sensitivity of 1.1 μA/μM with a correlation coefficient of 0.99. These properties make the prepared biosensor suitable for the analysis of trace detection of DA in most clinical preparations with a high sensitivity