Abstract:
The nano Fe
3O
4-reduced graphene oxide composite modified glassy carbon (Fe
3O
4-rGO/GC) electrode was fabricated by electrochemical reduction method, and used for the determination of dopamine (DA).The nano Fe
3O
4-rGO composites were characterized by SEM, TEM and cyclic voltammetry. The electrochemical behavior of DA was investigated in pH=7.0 phosphate buffer saline (PBS) by cyclic voltammetry. Compared with bare GC electrode and rGO-modified (rGO/GC) electrode, the electrochemical active area and the oxide peak current i
pa of Fe
3O
4-rGO/GC electrode increase significantly, owing to the synergistic action between nano Fe
3O
4 and rGO. The oxide peak current i
pa shows good linear relationship with the concentration of DA in the range of 6×10
-8-2×10
-6 mol/L and 2×10
-6-8×10
-5 mol/L. The detection limit is 4.0×10
-9 mol/L (signal-noise ratio
S/N=3).The determination of DA hardly interfere with the coexistence of ascorbic acid and uric acid. The proposed method is further applied to the determination of DA in DA injections with satisfied results, and the recovery of DA is 97.1%-103.9%.