Electrochemical Detection of Pb and Cu by Using DTPA Functionalized Magnetic Nanoparticles

Here, electrochemical determination of lead (Pb2+) and copper (Cu2+) ions, by using diethylenetriamine pentaacetic acid (DTPA) functionalized dopaminated Fe3O4 (Fe3O4/DA) magnetic nanoparticles, MNPs, (Fe3O4/DA/DTPA), is reported. First, step by step construction of Fe3O4/DA/DTPA was characterized and confirmed by spectroscopic methods. Then, a simple and new modified magnetic electrode was prepared by employing permanent magnet into a carbon paste electrode (MCPE) and collecting functionalized MNPs in each steps. The prepared modified electrodes, electrochemically characterized and further proofs was obtained in the presence of Fe(CN)(6)](3-/4-) as a redox probe. Sensing ability of the modified electrodes toward two valet cations was evaluated by following striping voltammetry responses of pre-concentrated ions on top of them. The MCPE/Fe3O4/DA/DTPA electrode showed selective response to Pb2+ and Cu2+ ions. Consequently, the electrode response to Pb2+ and Cu2+ was evaluated as a function of solution pH, pre-concentration time, and ions concentrations. Finally, in optimized conditions, two linear ranges from 1.0 x 10(-9) to 5.0 x 10(-6) and 1.0 x 10(-5) to 1.0 x 10(-3) M Pb2+ with a detection limit (D.L.) of 7.8 x 10(-10) M Pb2+, and a linear range from 5.0 x 10(-9) to 1.0 x 10(-3) M Cu2+ with a D.L. of 9.5 x 10(-10) M Cu2+ were observed for separate determination of Pb2+ and Cu2+, respectively. Also, two linear ranges from 1.0 x 10(-9) to 5.0 x 10(-8) and 5.0 x 10(-7) to 1.0 x 10(-3) M Pb2+ with a D.L. of 8.2 x 10(-9) M Pb2+, and a linear range from 5.0 x 10(-9) to 1.0 x 10(-4) M Cu2+ with a D.L. of 2.1 x 10(-9) M Cu2+ were observed for simultaneous determination of Pb2+ and Cu2+. The obtained results will be presented and described here. (C) 2013 Elsevier Ltd. All rights reserved.