Evaluation of sulfonated graphene sheets as sorbent for micro-solid-phase extraction combined with gas chromatography-mass spectrometry.

This report describes the use of sulfonated graphene sheets as sorbent in micro-solid-phase extraction (μ-SPE), together with gas chromatography-mass spectrometry, for the determination of polycyclic aromatic hydrocarbons (PAHs) in water. In this study, for the first time, graphene sheets were used as a sorbent material for this mode of microextraction. The modified graphene sheets were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, and elemental analysis. μ-SPE parameters such as extraction time, desorption time and desorption solvent were optimized. The method showed good precision, reproducibility and linear response for PAH analysis over a concentration range of 0.05-100 μg/L for naphthalene and 0.01-100 μg/L for the remaining PAHs (acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene) with coefficient of determination (r(2)) of higher than 0.992. Limits of detection of from 0.8 to 3.9 ng/L for 7 PAHs were achieved. The developed method was successfully applied to determine PAHs in river water samples.