Preparation of a Novel Gold Nanoparticles Directly Modified Glassy Carbon Electrode and Study on Its Electrocatalytic Activity

A novel gold nanoparticles modified glassy carbon electrode (Au/GC) was fabricated by the seed mediated growth method,without using cross-linking agents.As proved by SEM,nanoparticles of gold were successfully combined on the surface of glassy carbon electrode,having the surface coverage of 5.4×10-10mol·cm-2.It was found by testing with the redox electronic probe of Fe(CN)63-/Fe(CN)64-,that the speed of electron trasferring on the surface of this Au/GC electrode was about 4 times higher than that on the surface of gold nanoparticle modified GCE prepared by using cross-linking agents.The oxidative peak potential of ascorbic acid at the surface of Au/GC electrode was shifted negatively by 150 mV,and the peak current was raised by 2.2 μA.Difference of oxidative peak potentials between ascorbic acid and uric acid was attained to a value of 186 mV,which was feasible for the simultaneous determination of ascorbic acid and uric acid.