| Molecularly imprinted polymer belongs to functional high molecule polymer with specific recognition site for template and partial binding for structure analogues. At present, molecularly imprinted technology has borne a focus on developing a fast, simple and effective pre-preparation method for bio-sample in order to promote performance of model analysis instrument.In this dissertation, synthesis of molecularly imprinted polymer and non-molecularly imprinted polymer were based on for investigation of the interaction of seven different monomers with templates. 17β-estradiol and 4-androstene-3, 17-dione were used as templates, trimethylolpropane trimethacrylate was used as a cross-linker and two initiation modes of heat-polymerization and photo-polymerization were adopted. At last, the polymerization was implemented according to precipitation polymerization method. Morphologic appearance of molecularly imprinted polymer was measured by Laser Particle Analysis, Scan Electron Microscope and Atomic Force Microscope. Polymer selectivity recognition and enrichment properties with 17β-estradiol, 17α-estradiol, progesterone and 4-androstene-3, 17-dione were characterized through application of Fourier Transform Infrared Spectroscopy, Solid Phase Nuclear Magnetic Resonance, High Performance Liquid Chromatography, Gas-liquid Chromatograph-Mass Spectroscopy, Differential Scanning Calorimeter, Thermo gravimetric Analysis, Solid Phase Extraction and Solid Phase Micro-Extraction. In addition, adsorption kinetics and thermodynamics were adopted for revealing sorbent temperament.Several experiments were specially designed in the study. Changes in different polymerization stages of TFMAA-co-TRIM was detected by Fourier Transform Infrared Spectroscopy. Two columns loaded with MIPs from various rates of 17β-estradiol vs. trifluoromethyl acrylic acid (1/4 and 1/8) were tandem linked for improving separation characteristics. Recognition principle MIP of TFMAA-co-TRIM for sterol compounds was revealed by thermodynamics means. Elution files for specific adsorption of progesterone and enrichment of sterol compounds were arduously screened out from a mass of chemical reagents.The conclusions were as follows: theνO-H andνC=O IR absorption maxima shifted towards higher wave numbers after imprinting 17β-estradiol on TFMAA-co-TRIM copolymer with the red shift of theνO-H groups being apparent after precipitation polymerization for 16h while that forνC=O groups being observed after polymerization for 24h. A strong interaction between TFMAA and 17β-estradiol was confirmed by the high selectivity for 17β-estradiol, as indicted by the values of the separation factor (α) of isomers of 17β-estradiol/17α-estradiol (2.28) and the imprinted factor (IF) (3.01). Particle diameter of TFMAA-co-TRIM polymer was between 300 nm and 1.5μm, which suited well for solid phase sorbent throughout at low column pressure. The recognition of imprinting TFMAA-co-TRIM polymer for sterol molecules was driven by enthalpy eluted with acetronitile, and low temperature was in favor of the separation of sterol structure analogues on imprinting column. TFMAA-co-TRIM polymer possessed of determinate anti-heat stability, with melting point beginning at 255.84℃, Tp=257.40℃, control TFMAA-co-TRIM polymer and imprinting TFMAA-co-TRIM polymer were respectively decompounded at 267.79℃and 343.11℃, and solid micro-extraction noddle prepared by the special polymerization also showed definite recognition for 17β-estradiol by GC/MS detecting at 270℃. By selection of various washing and elution solvents, elution reagents of close polymerization system were of more advantage in template molecules retention and recognition on molecularly imprinted solid phase extraction (MISPE) column. At a certain extent, progesterone, 17α-estradiol, 17β-estradiol and 4-androstene-3, 17-dione could be intercepted on the MISPE column. Especially, MISPE had high selectivity for progesterone, and imprinting TFMAA-co-TRIM polymer could achieve adsorption balance within 50 min by absorption kinetics test for 17β-estradiol. However, MISPE column showed better selectivity and enrichment property for 17β-estradiol than C18 and CSPE columns according to the data from HPLC and GC/MS analyses. Recovery of 17β-estradiol on MISPE column was up to 85.5% while when prime extracting solution of milk powder was sampled, the recovery of CSPE and C18 columns were 43.7% and 30.7%, respectively. Thus, the imprinting TFMAA-co-TRIM polymer should be used as specific sorbent of sterol judging from the results obtained with a potential predominance as a sensitive material for sensors.
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