Simultaneous Determination of Dopamine,Ascorbic Acid and Uric Acid by Mesoporous Carbon/Gold Nanoparticle Modified Electrode

Au nanoparticles were loaded onto the ordered mesoporous carbon CMK-3 by a sol-gel method. The obtained composites were characterized by TEM,SEM and XRD. The Au/CMK-3 modified glassy carbon electrode (GCE) was used to simultaneously detect dopamine (DA),ascorbic acid (AA) and uric acid (UA) by cyclic voltammetry. In a PBS buffer solution (pH=7.2),the oxidation peaks of AA,DA and UA were well separated from each other. The Au/CMK-3 modified electrode displayed excellent electrochemical catalytic activities for DA,AA and UA. The intensity of the oxidation peak currents of DA、 AA and UA on Au/CMK-3 modified electrode was increased by 1.7,2,12 times,respectively,comparing with bare electrode. Linear relationship was found between the intensity of oxidation peak current of DA,AA and UA with the concentration in the range of 0.20-45.8,4.0-792.0,0.06-166.0 μmol·L-1 and the detection limits were 0.075,7.5,0.021 μmol·L-1,respectively.