Electrochemically grafted etodolac film on glassy carbon for Pb(II) determination

This study reports the electrochemical modification of glassy carbon (GC) surface with etodolac (ETO), the characterization of this ETO modified glassy carbon (ETO/GC) electrode and its electroanalytical application for the determination of Pb(II) ions. Binding type of the etodolac with the glassy carbon surface was investigated and found that it was through the etheric linkage revealed from the reflection–absorption infrared spectroscopy (RAIRS). The ETO/GC electrode was characterized by cyclic voltammetry (CV), reflection–adsorption IR spectroscopy, electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The ETO/GC electrode was found to be suitable for selective determination of Pb(II) by adsorptive stripping voltammetry in the solutions of the mixture of heavy metal ions, such as Cu(II) and Cd(II) and showed high stability and reproducibility. The stability and the potential range of the ETO/GC electrode were also studied. The developed method was validated according to the ICH guideline and found to be linear, sensitive, selective, precise and accurate. The linearity range of Pb(II) was 5.0 × 10−10 to 1.0 × 10−8 M with the detection limit (S/N = 3) of 1.67 × 10−10 M. The validated method was applied successfully for the determination of Pb(II) in real samples.