Application of Magnetic Graphene Nanoparticles for Determination of Organophosphorus Pesticides Using Solid-Phase Microextraction

In this study, a solid-phase microextraction (SPME) fiber based on ceramic-magnetic graphene (C-G/Fe3O4) nanoparticles was coated on a glass tube by sol-gel technology. Scanning electron micrographs of the fiber surface revealed a three-dimensional structure of the C-G/Fe3O4 nanoparticles making it suitable for SPME applications. Analytical application of the so-prepared fiber was evaluated through the extraction and determination of organophosphorus pesticides (OPPs) in water samples. Several experimental parameters affecting the extraction efficiency, such as extraction time, stirring rate, desorption conditions, salinity, and pH, were investigated and optimized. Under the optimized conditions, the linear response for the analytes was observed in the range 0.05-400 A mu g L-1 with the determination coefficients (R (2)) higher than 0.9944 and the limits of detection between 5 and 60 ng L-1. The C-G/Fe3O4 SPME fiber was successfully used for the extraction of OPPs in spiked water samples prior to determination by HPLC-UV.