Simultaneous voltammetric determination of molybdenum and copper by adsorption cathodic differential pulse stripping method using a principal component artificial neural network

An adsorption differential pulse stripping method for the simultaneous determination of molybdenum and copper based on the formation of their complexes with cupferron (benzene, N-hydroxy-N-nitroso) is proposed. The optimum experimental conditions were obtained 0.010 mM cupferron, pH 3.0, accumulation potential of −0.15 V versus Ag/AgCl, accumulation time of 60 s, scan rate of 10 mV s−1 and pulse height of 50 mV. Molybdenum and copper peak currents were observed at −0.16 and +0.02 V, respectively. A principal component artificial neural network (PC-ANN) was utilized for the analysis of the voltammogram data. A three layer back-propagation network was used with sigmoidal transfer function for the hidden and the output layers. The linear dynamic ranges were 5.0–60.0 and 0.1–20.0 ng ml−1 for Cu(II) and Mo(VI), respectively. The detection limit was 0.06 ng ml−1 for Mo(VI) and 0.20 ng ml−1 for Cu(II). The capability of the method for the analysis of real samples was evaluated by the determination of molybdenum and copper in river water, tap water, and alloy.