Determination of synthetic estrogens in milk by a novel hyper-crosslinked polymer SPME coupled with HPLC-MS.

[Display omitted] • Synthesis of soluble TCRA to insoluble HCP-TCRA by Friedel-Crafts alkylation reaction. • HCP-TCRA has strong hydrophobicity, which is conducive to the enrichment of SES in aqueous solutions. • The SPME fibers were used repeatedly for more than 30 times without any decrease in extraction effect. • The SPME fiber could extract estrogen directly from simple pretreated milk samples. A novel hyper-crosslinked 2, 8, 14, 20-tetraphenyl calix [4] resorcinol arene polymer (HCP-TCRA) was synthesized by using an external crosslinking of 2, 8, 14, 20-Tetraphenyl calix [4] resorcinol arene (TCRA) as monomers and dimethoxymethane as crosslinker. The HCP-TCRA was explored as a SPME fiber coating material. A variety of physicochemical characterization demonstrated that the material has excellent chemical/thermal stability and strong hydrophobicity. The fiber demonstrated fantastic adsorptive property for three synthetic estrogens (diethylstilbestrol, hexestrol, ethinyloestradiol, abbreviated to SESs). In this work, an efficient HCP-TCRA fiber-based SPME method was developed to analyze SESs by coupling with HPLC-MS detection. Under the optimized SPME conditions, this method was shown a wide range of linearity (2.0–100.0 ng mL−1 for diethylstilbestrol, 1.0–100.0 ng mL−1 for hexestrol, and 30.0–480.0 ng mL−1 for ethinyloestradiol), low limits of detection (LODs, 0.5 ng mL−1 for DES 0.3 ng mL−1 for HEX, 10.0 ng mL−1 for EES) and fine reusability (more than 30 times). Finally, the proposed methods had been applied to the determination of SESs in milk samples with a simple pretreatment. At three different levels, relative recoveries presented between 86.7 and 106.4%. The method put up highly sensitive and budget-friendly in detection SESs, and has capacity in quality control of milk products. [ABSTRACT FROM AUTHOR]