Application of an exfoliated graphite nanoplatelet-modified electrode for the determination of quintozen

A chitosan–grafted exfoliated graphite nanoplatelet (xGnP) hybrid chemically modified electrode was developed and characterized for the determination of organochlorine pesticides with nitro groups using quintozen as a representative. The hybrid material was characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–VIS) and scanning electron microscopy (SEM). The electrochemical properties of the chitosan–xGnP modified electrode were characterized by a physical deposition method for depositing it on a graphite electrode. Because of the affinity of the xGnP for nitro groups, nitroaromatic organophosphate pesticides are attached to the surface, allowing the extraction of quintozen within a short time (4 min). The differential pulse response was linear over the quintozen concentration range of 10−12–10−6 M, and the current linearly increased with the quintozen concentrations in two concentration ranges: from 10−12 to 10−8 M with the linear regression equation of y = 0.0423x + 0.6451, R2 = 0.9964 and from 10−8 to 10−6 M with the linear regression equation of y = 0.0085x + 0.303, R2 = 0.9952, with a detection limit of 10−11 M.