Non‐enzymatic electrochemical detection of dopamine in blood serum based on porous nitrogen‐doped graphene/Fe 3 O 4 nanocomposites

Fe3O4 with different shapes are reported herein to modify the glassy carbon electrode and then they are used to detect dopamine (DA), a member of the catecholamine and phenethylamine families. Cyclic voltammetry, electrochemical impedance spectroscopy, differential pulse voltammetry and linear sweep voltammetry are all chosen to characterise the sensor's performance to DA. Under the optimal conditions, the modified sensor (N-rGO/Fe3O4 NRs/GCE) had some good performance, followed as short response time (∼3 s), wide linear range (0.2–176 μM), low detection limit (0.05 μM, S/N = 2), good stability and reproducibility. The fabricated DA biosensor was further investigated for DA determination in human blood serum, suggesting its great potential in biological samples.