Electrocatalytic Determination of Cd2+ and Pb2+ using L-Cysteine Tungestophosphate Self-Assembled Monolayer on Polycrystalline Gold Electrode
In this study, a novel sensitive surface based on L-cysteine tungstophosphate modified polycrystalline gold electrode ((Cys)PW-Au) has been developed for electrochemical detection of Cd2+ and Pb2+ trace amounts. The electrocatalytic effect of this modified electrode toward Cd2+ and Pb2+ was evaluated by square wave voltammetry (SWV) as a sensitive method in the presence of these two analytes at bare and Au-(Cys)PW electrodes. The experimental conditions were optimized in order to evaluate the best analytical parameters of the sensor. A linear range of 0.01-0.2 µmol L-1 for both analytes, and detection limits of 9.0 nmol L-1 and 4.0 nmol L-1 for Cd2+ and Pb2+, respectively, based on the signal to noise ratio (S/N) equal to 3, have been achieved. The reproducibility and repeatability studies were also performed and the Au-(Cys)PW electrode was employed for the determination of Cd2+ or Pb2+ in an industrial wastewater sample which revealed the potential application of the modified electrode.