Fig. 3From: Fabrication of novel polymer-modified graphene-based electrochemical sensor for the determination of mercury and lead ions in water and biological samplesCyclic voltammograms for the electrochemical response of K4[Fe(CN)6] at the bare (curve b) and modified electrode (curve a) in 0.1 M KCl containing 1 mM K4[Fe(CN)6] at a scan rate of 0.1 V/sBack to article page