Isolation of organophosphate pesticides from water using gold nanoparticles doped magnetic three-dimensional graphene oxide

Pesticides are a large group of pristine organic contaminants, which are widely discharged into environmental water due to agricultural activities. Hence, extraction, determination, and removal of pesticides from water resources are necessary for human health. In this study, novel adsorbent was developed based on three-dimensional magnetic graphene coated with gold nanoparticles (3D-MG@AuNPs) for extraction of chlorpyri-fos, dicrotophos, fenitrothion, and piperophos as four specific organophosphorus pesticides (OPPs) from wastewater and tap water samples. The proposed nanocomposite was characterized; FTIR and EDX are per-formed for the expected functional groups and elemental analysis, SEM showed the unique and spherical AuNPs are well dispersed over graphene sheets. In this investigation, the important parameters that have effect on theextraction efficiency, including the desorbing solvent, desorbing solvent volume, vortex time, the extraction time, adsorbent dosage, pH of sample solutions, and salt effect were evaluated. In conclusion, the measured amounts of the chosen OPPs were determined using the gas chromatography microelectron capture (mu ECD-GC) method. Limits of quantification (S/N ratio of 10) and detection (S/N ratio of 3) were attained at concentrations of 0.26-0.43 mu g.L-1 and 0.08-0.14 mu g.L-1, respectively. According to the results of the investigations, the syn-thesized 3D-MG@AuNPs did not require any complicated sample preparation methods; therefore, it is a very good choice for solid magnetic phase extraction studies.

Automated summary

A novel adsorbent, 3D-MG@AuNPs, was developed for the extraction of specific organophosphorus pesticides (OPPs) from wastewater and tap water samples. The nanocomposite was characterized and evaluated for extraction efficiency under various parameters. The amounts of chosen OPPs were determined using gas chromatography microelectron capture (mu ECD-GC) method.