Abstract

The present document reports on the electrocatalytic activity of heavy metals (Copper(II), Nickel(II), Manganese(II) and Lead(II)) modified carbon paste electrodes (HM/CPE) for the paracetamol (Pr) oxidation where its results are compared with carbon paste electrode. The voltammetric behavior of Pr is explored where a sensitive anodic peak has appeared at about 0.27 V (vs. Ag/AgCl/3 M KCl) in 0.1 M Na₂SO₄ (pH 12). This peak results from the irreversible oxidation of Pr at HM/CPE surface. The catalytic effect was evaluated using cyclic and square wave voltammetry. Electrochemical impedance spectroscopy also confirms our experimental results as the HM/CPE shows the least charge transfer resistance. Also, HM/ CPE can be utilized successfully to ameliorate the electroanalysis of Pr at very weak concentration with excellent sensitivity. The calibration curves were linear from 6.0 · 10^-5 to 8.0 · 10^-4 mol L^-1. The detection limits were found approaching 10^-9 mol L^-1. Then, the proposed method was applied to detect Pr in river water samples with satisfactory results.

Keywords: heavy metals, cyclic voltammetry, square wave voltammetry, electrodeposition, modified electrodes, paracetamol

Article language: Eng