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Owing to the easy preparation,good stability,and recognition specificity,molecularly imprinted polymers(MIPs)have been demonstrated in many fields for the extraction and enrichment of target molecules[1],especially as solid phase extraction(SPE)sorbents in sample pretreatment of complicated matrixes.Recently,magnetic MIPs(MMIPs)have become a hotspot since the bifunctional property of the selectivity for the target molecule and the rapid magnetic response.However,MIPs prepared with traditional free radical polymerization(FRP)have met some defects such as broad size distribution,insufficient site accessibilities,and slow kinetics due to the undesired chain transfer and termination.To solve these problems,the reversible addition fragmentation chain transfer(RAFT)polymerization is particularly attractive not only because it is compatible with a wide range of monomers and allows postpolymerization modification,but also due to without using special catalyst under mild polymerization conditions[2].In the present work,the novel DES-MMIPs with uniform coating of imprinted shell were successfully synthesized using surface initiated RAFT polymerization for the analysis of synthetic estrogens.The superparamagnetic Fe3O4 nanoparticles were used as supporter and functionalized with a silica layer,which enabled the subsequent anchoring of RAFT agent.The resultant MMIPs were characterized by scanning electron microscopy(SEM),transmission electron microscope(TEM),vibrating sample magnetometer(VSM),Fourier transform infrared(FT-IR),and X-ray diffraction(XRD).The binding performances were evaluated by static and selective adsorption experiments.The binding isotherms were obtained for DES and fitted by the Langmuir isotherm(LI)model and Freundlich isotherm(FI)model.Furthermore,the applicability of the developed MMIPs as sorbent for real sample was further demonstrated by the simultaneous enrichment of four synthetic estrogens from fish pond water.