Determination of trace polycyclic aromatic hydrocarbons in water and milk using solid-phase extraction packed with graphene/chitosan composite aerogel prior to gas chromatography-mass spectrometry

Polycyclic aromatic hydrocarbons, ubiquitous compounds that result from incomplete combustion or pyrolysis of natural and man-made combustion sources, can adversely affects human health due to their well-known toxicity. This paper demonstrates the significant potential of graphene/chitosan composite aerogels as solid-phase extraction sorbents for efficient polycyclic aromatic hydrocarbon extraction and material for the highly sensitive analysis in environmental samples using gas chromatography-mass spectrometry in selective ion monitoring mode. Under the optimal condition, samples spiked with polycyclic aromatic hydrocarbons were determined at the pg/mL level in different aqueous sample matrices, including tap water, river water, and milk. The results showed that the prepared aerogels have excellent adsorption capability for 16 target analytes. The limits of detection ranged from 1.7 to 8.8 pg/mL. The recoveries of polycyclic aromatic hydrocarbons spiked in river water ranged from 85.9 to 113%, with relative standard deviations of 1.1-6.6%. The sorbent was reused for multiple polycyclic aromatic hydrocarbon extractions using a single solid-phase extraction cartridge in the concentration range of 10-2000 pg/mL. The method provides excellent correlation coefficients over 0.9990. These results indicate the capability of this method to determine trace polycyclic aromatic hydrocarbons in any water matrix.