Biomass-based green sorbent for high-performance extraction of polycyclic aromatic hydrocarbons from seawater by dispersive micro-solid-phase extraction coupled with gas chromatography-tandem mass spectrometry

A green, rapid, and cost-effective analytical method was developed for the quantification of fifteen polycyclic aromatic hydrocarbons in seawater using a seagrass-derived biomass sorbent in dispersive micro solid phase extraction coupled with gas chromatography-tandem mass spectrometry. Critical extraction factors including sorbent mass, desorption solvent, extraction time, desorption volume, and sample volume were systematically optimized to ensure high enrichment efficiency and reduced material consumption. The optimized workflow required only 10 mL of sample, 20 mg of sorbent, 30 min of extraction, 5 min of desorption, and 3.0 mL of n-hexane, providing a procedure that is both operationally simple and aligned with principles of green analytical chemistry. Under these conditions, the method achieved detection limits of 1.1–3.6 μg/L and quantification limits of 3.6–11.9 μg/L. Spiked seawater analyses provided recoveries of 94.3–102.4%, and relative standard deviations below 13.25% confirmed an acceptable precision. The greenness of the method was further evaluated using the sample preparation metric of sustainability and analytical greenness metric for sample preparation, which indicated a good sustainability profile and satisfactory analytical greenness. Overall, the seagrass-based dispersive micro solid phase extraction approach offers an efficient, sustainable, and high-performing strategy for the extraction and determination of polycyclic aromatic hydrocarbons in complex seawater samples.