Hollow mesoporous structured molecularly imprinted polymers for highly sensitive and selective detection 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 33-22ngL^-1. Thus, HM-MIPs-SPE method proved to be an accuracy and practical platform for detection of estrogens in food samples.