Fabrication of novel polymer-modified graphene-based electrochemical sensor for the determination of mercury and lead ions in water and biological samples

Abstract

Abstract Background This paper presents the application of polyglycine-modified graphene paste electrode (PGMGPE) for the electrochemical detection of Hg (II) and Pb (II) ions in the water and biological samples. Method The developed electrode was characterized by field emission scanning electron microscopy. Electrochemical techniques such as cyclic voltammetry and differential pulse voltammetry were used to study the behavior of metal ions. Results The modification process improves the electrochemical behavior of heavy metal ions. The peak current varied linearly with the increase of the concentration leading to a detection limit of 6.6 μM (Hg (II)) and 0.8 μM (Pb (II)), respectively. Conclusion The developed electrode exhibits good sensitivity, selectivity, stability, and lower detection limit, and was successfully applied to the determination of heavy metal ions in water and biological samples with a good recovery range.

Keywords

• HgCl2
• PbCl2
• Graphene
• Glycine
• Cyclic voltammetry
• Blood serum