Mesoporous structured estrone imprinted Fe3O4@SiO2@mSiO2 for highly sensitive and selective detection of estrogens from water samples by HPLC

In the present work, mesoporous structured estrone (E1) imprinted Fe3O4@SiO2@mSiO2 (MM-MIPs) was prepared and applied as extraction sorbent for selective pre-concentration and specific recognition of E1, 17β-estradiol (E2) and estriol (E3) from water samples. MM-MIPs present higher binding capacity, faster mass transfer and higher extraction efficiency for three estrogens than the non-porous structured Fe3O4@SiO2. Application of MM-MIPs to dispersive solid phase extraction of three estrogens from spiked tap, river and lake water samples at 0.5, 1.0, 10 μg L−1 resulted in good recoveries ranging from 85% to 95% with relative standard deviation values lower than 6.0% in all cases. Limits of detection were in the range of 0.086–0.43 μg L−1. The extraction method based on MM-MIPs proved to be a highly-effective enrichment method with enrichment factor about 1700, which is much higher than the value nearly 620 obtained by non-mesoporous Fe3O4@SiO2, during the process of simultaneous separation and sensitive determination of estrogens in complicated water samples. Furthermore, the mesoporous silica could be expanded to imprint other compounds.