EVALUATION OF NOVEL SOLID-PHASE EXTRACTION MICROSPHERES PREPARED BY A SURFACE IMPRINTING TECHNIQUE AND ITS APPLICATION TO THE SEPARATION OF DIETHYLSTILBESTROL FROM CHICKEN SAMPLES

A novel molecular imprinted solid-phase extraction technique was developed by using microspheres prepared by modifying the silica through a sol-gel process with a layer of homogeneous and compact molecularly imprinted polymer (MIP), which was synthesized with 3-aminopropyl-triethoxysilane and phenyltrimethoxysilane as functional monomers, diethylstilbestrol (DES) as the template, and tetraethoxysilane as the cross-linker. The saturated adsorption capacity of the MIP under the condition of continuous loading of target solution was 0.213 mg g(-1), and the imprinting factor reached 6.0. The selectivity factor of the MIPs for bisphenol A and 4-tert-butylphenol were 3.5 and 9.6, respectively. The molecular imprinted solid-phase extraction (MISPE) is a viable and efficient technique for extraction of DES from chicken samples with a recovery of more than 85%. The limit of detection (LOD) was determined to be 8 ng g(-1).