Microwave-assisted synthesis of reduced graphene oxide decorated with magnetite and gold nanoparticles, and its application to solid-phase extraction of organochlorine pesticides

An agent-free microwave-assisted method was developed for the preparation of a reduced graphene oxide/Fe3O4@gold nanocomposite. This material was used as an adsorbent for magnetic solid-phase extraction of organochlorine pesticides (OCPs) from water samples. The nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. The effects of sample volume, amount of sorbent, eluent volume, extraction and desorption time, and the effect of salt on the extraction efficiency were optimized. The linear response range of GC analysis extends from 0.05 to 500 mu g L-1 of OCPs, the limits of detection range from 0.4 to 4.1 ng L-1, relative standard deviations from 1.7 to 7.3 %, and recoveries (from spiked seawater samples) from 69 to 114 %.