Microwave-assisted synthesis of hyper-crosslinked polymer composite alginate hydrogel sorbent for dispersive...

A hyper-crosslinked polymer composite alginate hydrogel was developed as a sorbent for dispersive solid-phase extraction of phthalate esters. The hyper-crosslinked polymer was synthesized via microwave-assisted polymerization and subsequently embedded into the alginate hydrogel sorbent. Four extracted target analytes were quantified using high-performance liquid chromatography coupled with diode array detection. The method demonstrated good linearity with R² values exceeding 0.999 for all analytes. The linear ranges were 0.20 to 200 µg L^-1 for benzyl butyl phthalate and 0.5 to 200 µg L⁻¹ for dibutyl phthalate, di-2-ethylhexyl phthalate, and di-n-octyl phthalate. Limits of detection ranged from 0.05 to 0.15 µg L^-1, while limits of quantification ranged from 0.20 to 0.50 µg L^-1. The method exhibited high precision with intra-day and inter-day relative standard deviations (RSDs) between 1.1-3.2% and 1.7-3.7%, respectively. The sorbent showed good reproducibility with RSDs in the range of 0.9 to 4.9% and reusability for up to 11 cycles of adsorption-desorption. The efficiency of the method was comparable with that of a commercial cartridge. Recoveries of phthalate esters from drinking water and artificial tear samples ranged from 90.0 to 100.6%. The developed method was efficient and reliable for the analysis of phthalate esters.