Hollow mesoporous structured molecularly imprinted polymers for highly sensitive and selective detection of estrogens from food samples

- Hollow mesoporous MIPs (HM-MIPs) were prepared by chemical etching method.
- HM-MIPs have high binding capacity and fast mass transfer property.
- The HM-MIPs-SPE proves to be a highly-effective method for enrichment of estrogens.

Novel hollow mesoporous molecularly imprinted polymers (HM-MIPs) were proposed for highly selective and sensitive detection of estrogens in food samples. HM-MIPs were prepared by one-pot surface imprinting method using17β-estradiol (E2) as template followed by chemical selective etching to remove solid silica core. Transmission electron microscopy coupled with N2 adsorption experiment confirmed the successful formation of hollow mesoporous structure. Binding adsorption experiment indicated that HM-MIPs have high binding capacity and fast mass transfer property, and class selective recognition of estrogens is possible by E2 imprinted HM-MIPs. HM-MIPs-SPE-HPLC was employed to enrich and detect E1, E2 and E3 in cucumber, milk powder and grass carp samples. Satisfactory recoveries in the range of 85.6%-101.2% and relative standard deviation lower than 4.3% were obtained. The limits of detection for these estrogens were in the range of 33-22 ng L−1. Thus, HM-MIPs-SPE method proved to be an accuracy and practical platform for detection of estrogens in food samples.