Solvent and monomer regulation synthesis of core-shelled magnetic β-cyclodextrin microporous organic network for efficient extraction of estrogens in biological samples prior to HPLC analysis

The abnormal estrogens levels in human body can cause many side effects and diseases, but the quantitative detection of the trace estrogens in complex biological samples still remains great challenge. Here we reported the fabrication of a novel core-shell structured magnetic cyclodextrin microporous organic network (Fe 3 O 4 @CD-MON) for rapid magnetic solid phase extraction (MSPE) of four estrogens in human serum and urine samples prior to HPLC-UV determination. The uniform spherical core-shell Fe 3 O 4 @CD-MONs was successfully regulated by altering the reactive monomers and solvents. The Fe 3 O 4 @CD-MONs owned high specific surface area, good hydrophobicity, large superparamagnetism, and abundant extraction sites for estrogens. Under optimal conditions, the proposed MSPE-HPLC-UV method provided wide linearity range (2.0–400 μg L −1 ), low limits of detection (0.5–1.0 μg L −1 ), large enrichment factors (183–198), less adsorbent consumption (3 mg), short extraction time (3 min), and good stability and reusability (at least 8 cycles). The established method had also been successfully applied to the enrichment and detection of four estrogens in serum and urine samples with a recovery of 88.4–105.1 % and a relative standard deviation of 1.0–5.9 %. This work confirmed the feasibility of solvent and monomer regulation synthesis of Fe 3 O 4 @CD-MON composites, and revealed the great prospects of magnetic CD-MONs for efficient enrichment of trace estrogens in complex biological samples.