Determination of Environmental Estrogens by Polybenzothiophene-based Solid-phase Extraction (SPE) and High-Performance Liquid Chromatography (HPLC)

Porous polybenzothiophene was synthesized using Friedel-Crafts alkylation and applied as a sorbent for phase extraction. In combination with high performance liquid chromatography, a method for the simultaneous determination of the estrogens 17β-estradiol, ethinylestradiol, and diethylstilbestrol was established for environmental samples. Under the optimized conditions, satisfactory linearity was obtained from 2.0 to 1000.0 μg/L with the coefficients of determination (R2) exceeding 0.9977. The limits of detection were less than 0.3 μg/L for all targets, and the relative standard deviations (n = 5) were below 6.7%. The developed procedure was applied for the determination of estrogens in lake water, grass carp, and chicken manure. The recoveries of the targets were from 75.3% to 106.7%, 78.8% to 109.6%, and 89.1% to 114.5%, respectively. Ethinylestradiol was detected in lake water at 5.3 μg/L. None of the target compounds were present in the grass carp. Ethinylestradiol and diethylstilbestrol were observed in chicken manure at 0.9 μg/g and 0.6 μg/g. The developed method was simple and efficient for the determination of trace estrogens in complex samples.