Determination of environmental estrogens and bisphenol A in water samples by ultra-high performance liquid chromatography coupled to Q-Exactive high resolution mass spectrometry after magnetic solid-phase extraction

A novel, simple and rapid method based on the magnetic solid-phase extraction (MSPE) combined with ultra-high performance liquid chromatography coupled to Q-Exactive high resolution mass spectrometry (UHPLC-Q-Exactive HRMS) was developed for the determination of bisphenol A, 17 beta-estradiol, dienestrol, hexestrol, and diethylstilbestrol in water samples. In this study, novel aldehyde group functionalized core-shell mesoporous silica magnetic nanoparticles were used as adsorbents for purification and enrichment of the environmental estrogens and bisphenol A for the first time. The main factors including desorption solvent, adsorbent amount, adsorption time and desorption time affecting the performance of MSPE procedure were investigated in detail. Linearities with determination coefficients higher than 0.998 were obtained for all the target compounds, and the mean recoveries were in the range of 81.7-96.3%. The intra-day and inter-day precision were satisfactory with the relative standard deviations in the range of 2.3-8.1% and 3.5-9.9%, respectively. The limits of detection were found between 0.2 and 3.0 ng/L. Finally, the developed MSPE-UHPLC-Q-Exactive HRMS method was successfully applied for determination of the environmental estrogens and bisphenol A in water samples.