Electrochemical determination of dinitramine in water samples using a pencil graphite electrode modified with poly-l-cystein-gold nanoparticle

Abstract

In this work, the electrochemical determination of dinitramine was performed by adsorptive differential pulse voltammetry (AdDPV) as a sensitive method and using a pencil graphite electrode modified with poly-l-cystein-gold nanoparticles (PLC-AuNPs/PGE). The field emission scanning electron microscopy (FESEM), electrochemical impedance spectroscopy (EIS), and energy-dispersive X-ray spectroscopy (EDX) were used to investigate the electrochemical characteristics of the electrodes. After optimization of different parameters, including number of cycles and scan rate for polymerization of l-cystein and entrapment of AuNPs, pH, adsorptive time, adsorptive potential of dinitramine and step potential (Estep) in the AdDPV method, the signal of oxidation of dinitramine was obtained which linearity increased over the concentration range from 1.0 × 10–9 to 1.0 × 10–8 M and 1.0 × 10–8 to 5 × 10–6 M. The detection limit was obtained as 1.83 × 10–10 M and relative standard deviation was calculated as 2.5% for determination of 2.0 μM dinitramine. The proposed method was used to determine dinitramine in tap (drinking) and river waters. This was a new strategy with excellent sensitivity, reproducibility and stability to measure dinitramine.