Pulse anodic stripping voltammetric determination of copper with an amoxicillin-nafion modified glassy carbon electrode

The analysis of Cu2+by pulse anodic stripping voltammetry using a Nafion-modified glassy Carbon electrode incorporated with Amoxicillin is described. A significant increase in the voltammetric response was achieved at the modified electrode compared to a bare glassy carbon electrode. Cu2+ was accumulated in HAc-NaAc buffer (pH 3.6) at a potential of -0.7 V (vs. Ag/AgCl) for a certain time and then determined by pulse anodic stripping voltammetry. Parameters and conditions, such as the mass of Nafion, the concentration of Amoxicillin, the pH of medium, the accumulation potential, and the accumulation time were optimized. Under the optimum conditions, the calibration curve was linear in the range 8 x 10-10-2 x 10-8 M with a correlation coefficient of 0.9998 and relative standard deviation 4.87% (n = 5). The detection limit was 1.3 x 10-10s M. A study of interfering substances was also performed and the analytical utility of the method was demonstrated by applying to various pharmaceutical products.