Determination of Trace Amount of Mo(VI) in Natural Water and Food Samples by Differential Pulse Anodic Stripping Voltammetric Method

A differential pulse anodic stripping voltammetric method was based on the accumulation of Mo(VI) complex with phenylpiperazine dithiocarbamate on a hanging mercury drop electrode, followed by measurement of the current of the adsorbed complex. The effects of various parameters, such as reagent concentration, effect of pH of the medium, the accumulation potential, the accumulation time and the scan rate were investigated. Under the optimum conditions, a linear calibration graph was obtained in the concentration range of 0.01 to100 μg/mL with a correlation coefficient of 0.9994 and detection limit of 0.009 μg/mL. The effects of interference ions have been studied and it was found that the method is free from interferences of some common cations. The proposed method was applied for the determination of Mo(VI) in natural water and various food samples and the results showed good agreement with reported methods and the recoveries were in the range of 99.92 to 99.99 and 99.20 to 102.0 % respectively. The relative standard deviation for eight successive replicate analyses of Mo(VI) were 2.3% and 1.2%.