Cyclodextrin-starch hard gel as an efficient green sorbent for dispersive micro solid-phase extraction of eight polycyclic aromatic hydrocarbons from environmental water samples

Determination of organic pollutants in environmental water samples is known as the challenging field. In this study, we have reported an extraction methodology based on the β-cyclodextrin-starch composite (β-CD-starch) as a sorbent for the extraction of polycyclic aromatic hydrocarbons (PAHs) from water samples. The synthesis procedure of sorbent was straightforward and convenient. A hard gel of wheat starch in combination with different kinds of CDs/maltodextrin (MD) was prepared. It then was applied as a sorbent in dispersive micro solid-phase extraction (d-µ-SPE) of target analytes (i.e., naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, and benzo[a]pyrene) from aqueous solutions. Optimization of the extraction process was followed by the investigation of the effective parameters on the extraction efficiency; like sorbent type (based on the type of used CD/MD) and its mass amount, type and volume of desorption solvent, the salt concentration of sample solution, and the extraction/desorption times. Under the optimal extraction conditions, good linear ranges between 0.1 and 1000 ng/mL with r2 > 0.991 were obtained. The detection limit was from 0.01 to 0.07 ng/mL, and the limit of quantification was varied over the range 0.04–0.24 ng/mL. As well, the enrichment factor of the extraction method was calculated between 84.1 and 94.8 (with a maximum value of 100). The efficient and sensitive proposed method was then applied for extraction and determination of PAHs in agricultural and rainwater samples along with the GC-FID system, and acceptable results were received.