Using ethylene glycol as a growth directing agent, three-dimensional(3D) gold nanostructure(AuNS) was prepared on glassy carbon electrode by one-step electrochemical deposition. Copper ions was detected in strong salt electrolyte(0.5 mol/L NaCl solution) by square wave anodic stripping voltammetry(SWASV). Gold nanostructure could accelerate the rate of electron transfer. The three-dimensional electrode structure provided a larger specific surface area and more highly active binding sites. The optimal experimental conditions were as follows: the deposition potential was -0.1 V and the deposition time was 120 s. This modified electrode had a wide linear response to Cu(II) in the concentrations ranged from 0.02 μmol/L to 1 μmol/L(R~2 = 0.999) with the detection limit of 3 nmol/L(S/N = 3). The relative standard deviation for 100 measurements at the same modified electrode in the same copper standard solution was 3.7%. The modified electrode had been successfully applied to the detection of copper in seawater
