The sensitive monitoring of living cell-secreted dopamine based on the electrochemical biosensor modified with nitrogen-doped graphene aerogel/Co3O4 nanoparticles

Schematic illustration of the synthesis of Co-NGA and the application in the monitoring of living cell-secreted dopamine by Co-NGA/GCE. [Display omitted] •Nanohybrid of Co3O4 and nitrogen-doped graphene aerogels (Co-NGA) was synthesized.•The synergistic effect of Co-NGA enabled excellent electrocatalytic performance and high sensitivity towards DA.•Co-NGA/GCE was able to realize the real time monitoring of living cell-secreted DA. Real-time monitoring of dopamine in living cells is of great significance to the research and biomedical diagnosis of many central nervous system diseases. Since the release of dopamine (DA) from cells is instantaneous and few, an analytical strategy with high sensitivity and rapid response to DA is highly in needed. In this report, a novel electrochemical sensing system constructed by nitrogen-doped graphene aerogel/Co3O4 nanoparticles modified electrode (Co-NGA/GCE) was proposed. Benefiting from its effective conductivity, high surface area and catalytical activity, the Co-NGA/GCE performed an outstanding detection of DA from 0.05 − 200 μM and 200–1500 μM DA, with a limit of detection (LOD) of 12 nM, which was lower than most of the reported methods. It was proved that the Co-NGA/GCE was able to realize the real time monitoring of living cell-secreted DA under the K+ stimulation. It is anticipated that the Co-NGA/GCE will not only serve as an ideal tool for DA assay, but also offer a robust alternative to the pathogenesis research and drug screening of central nervous system diseases.