Preparation Of The Molecularly Imprinted Polymers By Frontal Polymerization

1. Frontal polymerization was successfully applied, for the first time, to prepare molecularly imprinted polymers (MIPs). The method provides a solvent-free polymerization mode, and the reaction can be completed in30min. By this approach, MIPs were synthesized using a mixture of levofloxacin (template), methacrylic acid, and divinylbenzene. The effect of template concentration and the amount of co-monomer on the imprinting effect of the resulting MIPs was investigated. The textural and morphological parameters of the MIP particles, e.g., median pore diameter, pore volumes, and pore size distributions were also characterized by mercury intrusion porosimetry, nitrogen adsorption isotherms, and scanning electron microscopy. The levofloxacin-imprinted polymer formed in frontal polymerization mode showed high selectivity, with an imprinting factor of5.78. The results suggest that frontal polymerization provides an alternative means to prepare MIPS that are difficult to synthesize and may open up new perspectives in the field of MIPs.2. Isothermality frontal polymerization was utilized to obtain ketoprofen molecularly imprinted monolithic column, ketoprofen and its structure analogues were investigated. The results showed that imprinting factor of ketoprofen in ketoprofen imprinted monolithic column was6.33. Monolithic columns synthesized by isothermal frontal polymerization and in situ polymerization were compared by permeability, column efficiency, surface morphology and pore size distribution. The influence of synthesis parameters (the average molar mass of polystyrene, the rate of template to monomer, and the rate of monomer to crosslinker) was investigated; the retention effect and imprinted factor were also investigated. The results showed that the imprinted factors were increased as the amount of monomer. The content of crosslinker also affected the imprinting effect. T:M:C=1:5:22.5for ketoprofen imprinted monolithic column were the optimal with an imprinted factor of6.33. Chromatographic conditions of monolithic column were systematic studied, such as the pH value, the content of acetic acid and column temperature. It turned out that when the pH of moving phase was3.6, the retention factor was the maximum. The main factors of the test were the affinity between the solute and stationary phase, the separation process of molecular imprinting monolithic column was an enthalpy control process.